[linux-2.6-microblaze.git] / arch / x86 / kvm / vmx / vmx.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Kernel-based Virtual Machine driver for Linux
 *
 * This module enables machines with Intel VT-x extensions to run virtual
 * machines without emulation or binary translation.
 *
 * Copyright (C) 2006 Qumranet, Inc.
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * Authors:
 *   Avi Kivity   <avi@qumranet.com>
 *   Yaniv Kamay  <yaniv@qumranet.com>
 */

#include <linux/frame.h>
#include <linux/highmem.h>
#include <linux/hrtimer.h>
#include <linux/kernel.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/mod_devicetable.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/sched/smt.h>
#include <linux/slab.h>
#include <linux/tboot.h>
#include <linux/trace_events.h>
#include <linux/entry-kvm.h>

#include <asm/apic.h>
#include <asm/asm.h>
#include <asm/cpu.h>
#include <asm/cpu_device_id.h>
#include <asm/debugreg.h>
#include <asm/desc.h>
#include <asm/fpu/internal.h>
#include <asm/io.h>
#include <asm/irq_remapping.h>
#include <asm/kexec.h>
#include <asm/perf_event.h>
#include <asm/mce.h>
#include <asm/mmu_context.h>
#include <asm/mshyperv.h>
#include <asm/mwait.h>
#include <asm/spec-ctrl.h>
#include <asm/virtext.h>
#include <asm/vmx.h>

#include "capabilities.h"
#include "cpuid.h"
#include "evmcs.h"
#include "irq.h"
#include "kvm_cache_regs.h"
#include "lapic.h"
#include "mmu.h"
#include "nested.h"
#include "pmu.h"
#include "trace.h"
#include "vmcs.h"
#include "vmcs12.h"
#include "vmx.h"
#include "x86.h"

MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");

#ifdef MODULE
static const struct x86_cpu_id vmx_cpu_id[] = {
        X86_MATCH_FEATURE(X86_FEATURE_VMX, NULL),
        {}
};
MODULE_DEVICE_TABLE(x86cpu, vmx_cpu_id);
#endif

bool __read_mostly enable_vpid = 1;
module_param_named(vpid, enable_vpid, bool, 0444);

static bool __read_mostly enable_vnmi = 1;
module_param_named(vnmi, enable_vnmi, bool, S_IRUGO);

bool __read_mostly flexpriority_enabled = 1;
module_param_named(flexpriority, flexpriority_enabled, bool, S_IRUGO);

bool __read_mostly enable_ept = 1;
module_param_named(ept, enable_ept, bool, S_IRUGO);

bool __read_mostly enable_unrestricted_guest = 1;
module_param_named(unrestricted_guest,
                        enable_unrestricted_guest, bool, S_IRUGO);

bool __read_mostly enable_ept_ad_bits = 1;
module_param_named(eptad, enable_ept_ad_bits, bool, S_IRUGO);

static bool __read_mostly emulate_invalid_guest_state = true;
module_param(emulate_invalid_guest_state, bool, S_IRUGO);

static bool __read_mostly fasteoi = 1;
module_param(fasteoi, bool, S_IRUGO);

bool __read_mostly enable_apicv = 1;
module_param(enable_apicv, bool, S_IRUGO);

/*
 * If nested=1, nested virtualization is supported, i.e., guests may use
 * VMX and be a hypervisor for its own guests. If nested=0, guests may not
 * use VMX instructions.
 */
static bool __read_mostly nested = 1;
module_param(nested, bool, S_IRUGO);

bool __read_mostly enable_pml = 1;
module_param_named(pml, enable_pml, bool, S_IRUGO);

static bool __read_mostly dump_invalid_vmcs = 0;
module_param(dump_invalid_vmcs, bool, 0644);

#define MSR_BITMAP_MODE_X2APIC          1
#define MSR_BITMAP_MODE_X2APIC_APICV    2

#define KVM_VMX_TSC_MULTIPLIER_MAX     0xffffffffffffffffULL

/* Guest_tsc -> host_tsc conversion requires 64-bit division.  */
static int __read_mostly cpu_preemption_timer_multi;
static bool __read_mostly enable_preemption_timer = 1;
#ifdef CONFIG_X86_64
module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
#endif

#define KVM_VM_CR0_ALWAYS_OFF (X86_CR0_NW | X86_CR0_CD)
#define KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST X86_CR0_NE
#define KVM_VM_CR0_ALWAYS_ON                            \
        (KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST |      \
         X86_CR0_WP | X86_CR0_PG | X86_CR0_PE)

#define KVM_VM_CR4_ALWAYS_ON_UNRESTRICTED_GUEST X86_CR4_VMXE
#define KVM_PMODE_VM_CR4_ALWAYS_ON (X86_CR4_PAE | X86_CR4_VMXE)
#define KVM_RMODE_VM_CR4_ALWAYS_ON (X86_CR4_VME | X86_CR4_PAE | X86_CR4_VMXE)

#define RMODE_GUEST_OWNED_EFLAGS_BITS (~(X86_EFLAGS_IOPL | X86_EFLAGS_VM))

#define MSR_IA32_RTIT_STATUS_MASK (~(RTIT_STATUS_FILTEREN | \
        RTIT_STATUS_CONTEXTEN | RTIT_STATUS_TRIGGEREN | \
        RTIT_STATUS_ERROR | RTIT_STATUS_STOPPED | \
        RTIT_STATUS_BYTECNT))

/*
 * These 2 parameters are used to config the controls for Pause-Loop Exiting:
 * ple_gap:    upper bound on the amount of time between two successive
 *             executions of PAUSE in a loop. Also indicate if ple enabled.
 *             According to test, this time is usually smaller than 128 cycles.
 * ple_window: upper bound on the amount of time a guest is allowed to execute
 *             in a PAUSE loop. Tests indicate that most spinlocks are held for
 *             less than 2^12 cycles
 * Time is measured based on a counter that runs at the same rate as the TSC,
 * refer SDM volume 3b section 21.6.13 & 22.1.3.
 */
static unsigned int ple_gap = KVM_DEFAULT_PLE_GAP;
module_param(ple_gap, uint, 0444);

static unsigned int ple_window = KVM_VMX_DEFAULT_PLE_WINDOW;
module_param(ple_window, uint, 0444);

/* Default doubles per-vcpu window every exit. */
static unsigned int ple_window_grow = KVM_DEFAULT_PLE_WINDOW_GROW;
module_param(ple_window_grow, uint, 0444);

/* Default resets per-vcpu window every exit to ple_window. */
static unsigned int ple_window_shrink = KVM_DEFAULT_PLE_WINDOW_SHRINK;
module_param(ple_window_shrink, uint, 0444);

/* Default is to compute the maximum so we can never overflow. */
static unsigned int ple_window_max        = KVM_VMX_DEFAULT_PLE_WINDOW_MAX;
module_param(ple_window_max, uint, 0444);

/* Default is SYSTEM mode, 1 for host-guest mode */
int __read_mostly pt_mode = PT_MODE_SYSTEM;
module_param(pt_mode, int, S_IRUGO);

static DEFINE_STATIC_KEY_FALSE(vmx_l1d_should_flush);
static DEFINE_STATIC_KEY_FALSE(vmx_l1d_flush_cond);
static DEFINE_MUTEX(vmx_l1d_flush_mutex);

/* Storage for pre module init parameter parsing */
static enum vmx_l1d_flush_state __read_mostly vmentry_l1d_flush_param = VMENTER_L1D_FLUSH_AUTO;

static const struct {
        const char *option;
        bool for_parse;
} vmentry_l1d_param[] = {
        [VMENTER_L1D_FLUSH_AUTO]         = {"auto", true},
        [VMENTER_L1D_FLUSH_NEVER]        = {"never", true},
        [VMENTER_L1D_FLUSH_COND]         = {"cond", true},
        [VMENTER_L1D_FLUSH_ALWAYS]       = {"always", true},
        [VMENTER_L1D_FLUSH_EPT_DISABLED] = {"EPT disabled", false},
        [VMENTER_L1D_FLUSH_NOT_REQUIRED] = {"not required", false},
};

#define L1D_CACHE_ORDER 4
static void *vmx_l1d_flush_pages;

static int vmx_setup_l1d_flush(enum vmx_l1d_flush_state l1tf)
{
        struct page *page;
        unsigned int i;

        if (!boot_cpu_has_bug(X86_BUG_L1TF)) {
                l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NOT_REQUIRED;
                return 0;
        }

        if (!enable_ept) {
                l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_EPT_DISABLED;
                return 0;
        }

        if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES)) {
                u64 msr;

                rdmsrl(MSR_IA32_ARCH_CAPABILITIES, msr);
                if (msr & ARCH_CAP_SKIP_VMENTRY_L1DFLUSH) {
                        l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NOT_REQUIRED;
                        return 0;
                }
        }

        /* If set to auto use the default l1tf mitigation method */
        if (l1tf == VMENTER_L1D_FLUSH_AUTO) {
                switch (l1tf_mitigation) {
                case L1TF_MITIGATION_OFF:
                        l1tf = VMENTER_L1D_FLUSH_NEVER;
                        break;
                case L1TF_MITIGATION_FLUSH_NOWARN:
                case L1TF_MITIGATION_FLUSH:
                case L1TF_MITIGATION_FLUSH_NOSMT:
                        l1tf = VMENTER_L1D_FLUSH_COND;
                        break;
                case L1TF_MITIGATION_FULL:
                case L1TF_MITIGATION_FULL_FORCE:
                        l1tf = VMENTER_L1D_FLUSH_ALWAYS;
                        break;
                }
        } else if (l1tf_mitigation == L1TF_MITIGATION_FULL_FORCE) {
                l1tf = VMENTER_L1D_FLUSH_ALWAYS;
        }

        if (l1tf != VMENTER_L1D_FLUSH_NEVER && !vmx_l1d_flush_pages &&
            !boot_cpu_has(X86_FEATURE_FLUSH_L1D)) {
                /*
                 * This allocation for vmx_l1d_flush_pages is not tied to a VM
                 * lifetime and so should not be charged to a memcg.
                 */
                page = alloc_pages(GFP_KERNEL, L1D_CACHE_ORDER);
                if (!page)
                        return -ENOMEM;
                vmx_l1d_flush_pages = page_address(page);

                /*
                 * Initialize each page with a different pattern in
                 * order to protect against KSM in the nested
                 * virtualization case.
                 */
                for (i = 0; i < 1u << L1D_CACHE_ORDER; ++i) {
                        memset(vmx_l1d_flush_pages + i * PAGE_SIZE, i + 1,
                               PAGE_SIZE);
                }
        }

        l1tf_vmx_mitigation = l1tf;

        if (l1tf != VMENTER_L1D_FLUSH_NEVER)
                static_branch_enable(&vmx_l1d_should_flush);
        else
                static_branch_disable(&vmx_l1d_should_flush);

        if (l1tf == VMENTER_L1D_FLUSH_COND)
                static_branch_enable(&vmx_l1d_flush_cond);
        else
                static_branch_disable(&vmx_l1d_flush_cond);
        return 0;
}

static int vmentry_l1d_flush_parse(const char *s)
{
        unsigned int i;

        if (s) {
                for (i = 0; i < ARRAY_SIZE(vmentry_l1d_param); i++) {
                        if (vmentry_l1d_param[i].for_parse &&
                            sysfs_streq(s, vmentry_l1d_param[i].option))
                                return i;
                }
        }
        return -EINVAL;
}

static int vmentry_l1d_flush_set(const char *s, const struct kernel_param *kp)
{
        int l1tf, ret;

        l1tf = vmentry_l1d_flush_parse(s);
        if (l1tf < 0)
                return l1tf;

        if (!boot_cpu_has(X86_BUG_L1TF))
                return 0;

        /*
         * Has vmx_init() run already? If not then this is the pre init
         * parameter parsing. In that case just store the value and let
         * vmx_init() do the proper setup after enable_ept has been
         * established.
         */
        if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_AUTO) {
                vmentry_l1d_flush_param = l1tf;
                return 0;
        }

        mutex_lock(&vmx_l1d_flush_mutex);
        ret = vmx_setup_l1d_flush(l1tf);
        mutex_unlock(&vmx_l1d_flush_mutex);
        return ret;
}

static int vmentry_l1d_flush_get(char *s, const struct kernel_param *kp)
{
        if (WARN_ON_ONCE(l1tf_vmx_mitigation >= ARRAY_SIZE(vmentry_l1d_param)))
                return sprintf(s, "???\n");

        return sprintf(s, "%s\n", vmentry_l1d_param[l1tf_vmx_mitigation].option);
}

static const struct kernel_param_ops vmentry_l1d_flush_ops = {
        .set = vmentry_l1d_flush_set,
        .get = vmentry_l1d_flush_get,
};
module_param_cb(vmentry_l1d_flush, &vmentry_l1d_flush_ops, NULL, 0644);

static u32 vmx_segment_access_rights(struct kvm_segment *var);
static __always_inline void vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
                                                          u32 msr, int type);

void vmx_vmexit(void);

#define vmx_insn_failed(fmt...)         \
do {                                    \
        WARN_ONCE(1, fmt);              \
        pr_warn_ratelimited(fmt);       \
} while (0)

asmlinkage void vmread_error(unsigned long field, bool fault)
{
        if (fault)
                kvm_spurious_fault();
        else
                vmx_insn_failed("kvm: vmread failed: field=%lx\n", field);
}

noinline void vmwrite_error(unsigned long field, unsigned long value)
{
        vmx_insn_failed("kvm: vmwrite failed: field=%lx val=%lx err=%d\n",
                        field, value, vmcs_read32(VM_INSTRUCTION_ERROR));
}

noinline void vmclear_error(struct vmcs *vmcs, u64 phys_addr)
{
        vmx_insn_failed("kvm: vmclear failed: %p/%llx\n", vmcs, phys_addr);
}

noinline void vmptrld_error(struct vmcs *vmcs, u64 phys_addr)
{
        vmx_insn_failed("kvm: vmptrld failed: %p/%llx\n", vmcs, phys_addr);
}

noinline void invvpid_error(unsigned long ext, u16 vpid, gva_t gva)
{
        vmx_insn_failed("kvm: invvpid failed: ext=0x%lx vpid=%u gva=0x%lx\n",
                        ext, vpid, gva);
}

noinline void invept_error(unsigned long ext, u64 eptp, gpa_t gpa)
{
        vmx_insn_failed("kvm: invept failed: ext=0x%lx eptp=%llx gpa=0x%llx\n",
                        ext, eptp, gpa);
}

static DEFINE_PER_CPU(struct vmcs *, vmxarea);
DEFINE_PER_CPU(struct vmcs *, current_vmcs);
/*
 * We maintain a per-CPU linked-list of VMCS loaded on that CPU. This is needed
 * when a CPU is brought down, and we need to VMCLEAR all VMCSs loaded on it.
 */
static DEFINE_PER_CPU(struct list_head, loaded_vmcss_on_cpu);

static DECLARE_BITMAP(vmx_vpid_bitmap, VMX_NR_VPIDS);
static DEFINE_SPINLOCK(vmx_vpid_lock);

struct vmcs_config vmcs_config;
struct vmx_capability vmx_capability;

#define VMX_SEGMENT_FIELD(seg)                                  \
        [VCPU_SREG_##seg] = {                                   \
                .selector = GUEST_##seg##_SELECTOR,             \
                .base = GUEST_##seg##_BASE,                     \
                .limit = GUEST_##seg##_LIMIT,                   \
                .ar_bytes = GUEST_##seg##_AR_BYTES,             \
        }

static const struct kvm_vmx_segment_field {
        unsigned selector;
        unsigned base;
        unsigned limit;
        unsigned ar_bytes;
} kvm_vmx_segment_fields[] = {
        VMX_SEGMENT_FIELD(CS),
        VMX_SEGMENT_FIELD(DS),
        VMX_SEGMENT_FIELD(ES),
        VMX_SEGMENT_FIELD(FS),
        VMX_SEGMENT_FIELD(GS),
        VMX_SEGMENT_FIELD(SS),
        VMX_SEGMENT_FIELD(TR),
        VMX_SEGMENT_FIELD(LDTR),
};

static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx)
{
        vmx->segment_cache.bitmask = 0;
}

static unsigned long host_idt_base;

/*
 * Though SYSCALL is only supported in 64-bit mode on Intel CPUs, kvm
 * will emulate SYSCALL in legacy mode if the vendor string in guest
 * CPUID.0:{EBX,ECX,EDX} is "AuthenticAMD" or "AMDisbetter!" To
 * support this emulation, IA32_STAR must always be included in
 * vmx_msr_index[], even in i386 builds.
 */
const u32 vmx_msr_index[] = {
#ifdef CONFIG_X86_64
        MSR_SYSCALL_MASK, MSR_LSTAR, MSR_CSTAR,
#endif
        MSR_EFER, MSR_TSC_AUX, MSR_STAR,
        MSR_IA32_TSX_CTRL,
};

#if IS_ENABLED(CONFIG_HYPERV)
static bool __read_mostly enlightened_vmcs = true;
module_param(enlightened_vmcs, bool, 0444);

/* check_ept_pointer() should be under protection of ept_pointer_lock. */
static void check_ept_pointer_match(struct kvm *kvm)
{
        struct kvm_vcpu *vcpu;
        u64 tmp_eptp = INVALID_PAGE;
        int i;

        kvm_for_each_vcpu(i, vcpu, kvm) {
                if (!VALID_PAGE(tmp_eptp)) {
                        tmp_eptp = to_vmx(vcpu)->ept_pointer;
                } else if (tmp_eptp != to_vmx(vcpu)->ept_pointer) {
                        to_kvm_vmx(kvm)->ept_pointers_match
                                = EPT_POINTERS_MISMATCH;
                        return;
                }
        }

        to_kvm_vmx(kvm)->ept_pointers_match = EPT_POINTERS_MATCH;
}

static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,
                void *data)
{
        struct kvm_tlb_range *range = data;

        return hyperv_fill_flush_guest_mapping_list(flush, range->start_gfn,
                        range->pages);
}

static inline int __hv_remote_flush_tlb_with_range(struct kvm *kvm,
                struct kvm_vcpu *vcpu, struct kvm_tlb_range *range)
{
        u64 ept_pointer = to_vmx(vcpu)->ept_pointer;

        /*
         * FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE hypercall needs address
         * of the base of EPT PML4 table, strip off EPT configuration
         * information.
         */
        if (range)
                return hyperv_flush_guest_mapping_range(ept_pointer & PAGE_MASK,
                                kvm_fill_hv_flush_list_func, (void *)range);
        else
                return hyperv_flush_guest_mapping(ept_pointer & PAGE_MASK);
}

static int hv_remote_flush_tlb_with_range(struct kvm *kvm,
                struct kvm_tlb_range *range)
{
        struct kvm_vcpu *vcpu;
        int ret = 0, i;

        spin_lock(&to_kvm_vmx(kvm)->ept_pointer_lock);

        if (to_kvm_vmx(kvm)->ept_pointers_match == EPT_POINTERS_CHECK)
                check_ept_pointer_match(kvm);

        if (to_kvm_vmx(kvm)->ept_pointers_match != EPT_POINTERS_MATCH) {
                kvm_for_each_vcpu(i, vcpu, kvm) {
                        /* If ept_pointer is invalid pointer, bypass flush request. */
                        if (VALID_PAGE(to_vmx(vcpu)->ept_pointer))
                                ret |= __hv_remote_flush_tlb_with_range(
                                        kvm, vcpu, range);
                }
        } else {
                ret = __hv_remote_flush_tlb_with_range(kvm,
                                kvm_get_vcpu(kvm, 0), range);
        }

        spin_unlock(&to_kvm_vmx(kvm)->ept_pointer_lock);
        return ret;
}
static int hv_remote_flush_tlb(struct kvm *kvm)
{
        return hv_remote_flush_tlb_with_range(kvm, NULL);
}

static int hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
{
        struct hv_enlightened_vmcs *evmcs;
        struct hv_partition_assist_pg **p_hv_pa_pg =
                        &vcpu->kvm->arch.hyperv.hv_pa_pg;
        /*
         * Synthetic VM-Exit is not enabled in current code and so All
         * evmcs in singe VM shares same assist page.
         */
        if (!*p_hv_pa_pg)
                *p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL);

        if (!*p_hv_pa_pg)
                return -ENOMEM;

        evmcs = (struct hv_enlightened_vmcs *)to_vmx(vcpu)->loaded_vmcs->vmcs;

        evmcs->partition_assist_page =
                __pa(*p_hv_pa_pg);
        evmcs->hv_vm_id = (unsigned long)vcpu->kvm;
        evmcs->hv_enlightenments_control.nested_flush_hypercall = 1;

        return 0;
}

#endif /* IS_ENABLED(CONFIG_HYPERV) */

/*
 * Comment's format: document - errata name - stepping - processor name.
 * Refer from
 * https://www.virtualbox.org/svn/vbox/trunk/src/VBox/VMM/VMMR0/HMR0.cpp
 */
static u32 vmx_preemption_cpu_tfms[] = {
/* 323344.pdf - BA86   - D0 - Xeon 7500 Series */
0x000206E6,
/* 323056.pdf - AAX65  - C2 - Xeon L3406 */
/* 322814.pdf - AAT59  - C2 - i7-600, i5-500, i5-400 and i3-300 Mobile */
/* 322911.pdf - AAU65  - C2 - i5-600, i3-500 Desktop and Pentium G6950 */
0x00020652,
/* 322911.pdf - AAU65  - K0 - i5-600, i3-500 Desktop and Pentium G6950 */
0x00020655,
/* 322373.pdf - AAO95  - B1 - Xeon 3400 Series */
/* 322166.pdf - AAN92  - B1 - i7-800 and i5-700 Desktop */
/*
 * 320767.pdf - AAP86  - B1 -
 * i7-900 Mobile Extreme, i7-800 and i7-700 Mobile
 */
0x000106E5,
/* 321333.pdf - AAM126 - C0 - Xeon 3500 */
0x000106A0,
/* 321333.pdf - AAM126 - C1 - Xeon 3500 */
0x000106A1,
/* 320836.pdf - AAJ124 - C0 - i7-900 Desktop Extreme and i7-900 Desktop */
0x000106A4,
 /* 321333.pdf - AAM126 - D0 - Xeon 3500 */
 /* 321324.pdf - AAK139 - D0 - Xeon 5500 */
 /* 320836.pdf - AAJ124 - D0 - i7-900 Extreme and i7-900 Desktop */
0x000106A5,
 /* Xeon E3-1220 V2 */
0x000306A8,
};

static inline bool cpu_has_broken_vmx_preemption_timer(void)
{
        u32 eax = cpuid_eax(0x00000001), i;

        /* Clear the reserved bits */
        eax &= ~(0x3U << 14 | 0xfU << 28);
        for (i = 0; i < ARRAY_SIZE(vmx_preemption_cpu_tfms); i++)
                if (eax == vmx_preemption_cpu_tfms[i])
                        return true;

        return false;
}

static inline bool cpu_need_virtualize_apic_accesses(struct kvm_vcpu *vcpu)
{
        return flexpriority_enabled && lapic_in_kernel(vcpu);
}

static inline bool report_flexpriority(void)
{
        return flexpriority_enabled;
}

static inline int __find_msr_index(struct vcpu_vmx *vmx, u32 msr)
{
        int i;

        for (i = 0; i < vmx->nr_uret_msrs; ++i)
                if (vmx_msr_index[vmx->guest_uret_msrs[i].index] == msr)
                        return i;
        return -1;
}

struct vmx_uret_msr *find_msr_entry(struct vcpu_vmx *vmx, u32 msr)
{
        int i;

        i = __find_msr_index(vmx, msr);
        if (i >= 0)
                return &vmx->guest_uret_msrs[i];
        return NULL;
}

static int vmx_set_guest_msr(struct vcpu_vmx *vmx, struct vmx_uret_msr *msr, u64 data)
{
        int ret = 0;

        u64 old_msr_data = msr->data;
        msr->data = data;
        if (msr - vmx->guest_uret_msrs < vmx->nr_active_uret_msrs) {
                preempt_disable();
                ret = kvm_set_user_return_msr(msr->index, msr->data, msr->mask);
                preempt_enable();
                if (ret)
                        msr->data = old_msr_data;
        }
        return ret;
}

#ifdef CONFIG_KEXEC_CORE
static void crash_vmclear_local_loaded_vmcss(void)
{
        int cpu = raw_smp_processor_id();
        struct loaded_vmcs *v;

        list_for_each_entry(v, &per_cpu(loaded_vmcss_on_cpu, cpu),
                            loaded_vmcss_on_cpu_link)
                vmcs_clear(v->vmcs);
}
#endif /* CONFIG_KEXEC_CORE */

static void __loaded_vmcs_clear(void *arg)
{
        struct loaded_vmcs *loaded_vmcs = arg;
        int cpu = raw_smp_processor_id();

        if (loaded_vmcs->cpu != cpu)
                return; /* vcpu migration can race with cpu offline */
        if (per_cpu(current_vmcs, cpu) == loaded_vmcs->vmcs)
                per_cpu(current_vmcs, cpu) = NULL;

        vmcs_clear(loaded_vmcs->vmcs);
        if (loaded_vmcs->shadow_vmcs && loaded_vmcs->launched)
                vmcs_clear(loaded_vmcs->shadow_vmcs);

        list_del(&loaded_vmcs->loaded_vmcss_on_cpu_link);

        /*
         * Ensure all writes to loaded_vmcs, including deleting it from its
         * current percpu list, complete before setting loaded_vmcs->vcpu to
         * -1, otherwise a different cpu can see vcpu == -1 first and add
         * loaded_vmcs to its percpu list before it's deleted from this cpu's
         * list. Pairs with the smp_rmb() in vmx_vcpu_load_vmcs().
         */
        smp_wmb();

        loaded_vmcs->cpu = -1;
        loaded_vmcs->launched = 0;
}

void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs)
{
        int cpu = loaded_vmcs->cpu;

        if (cpu != -1)
                smp_call_function_single(cpu,
                         __loaded_vmcs_clear, loaded_vmcs, 1);
}

static bool vmx_segment_cache_test_set(struct vcpu_vmx *vmx, unsigned seg,
                                       unsigned field)
{
        bool ret;
        u32 mask = 1 << (seg * SEG_FIELD_NR + field);

        if (!kvm_register_is_available(&vmx->vcpu, VCPU_EXREG_SEGMENTS)) {
                kvm_register_mark_available(&vmx->vcpu, VCPU_EXREG_SEGMENTS);
                vmx->segment_cache.bitmask = 0;
        }
        ret = vmx->segment_cache.bitmask & mask;
        vmx->segment_cache.bitmask |= mask;
        return ret;
}

static u16 vmx_read_guest_seg_selector(struct vcpu_vmx *vmx, unsigned seg)
{
        u16 *p = &vmx->segment_cache.seg[seg].selector;

        if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_SEL))
                *p = vmcs_read16(kvm_vmx_segment_fields[seg].selector);
        return *p;
}

static ulong vmx_read_guest_seg_base(struct vcpu_vmx *vmx, unsigned seg)
{
        ulong *p = &vmx->segment_cache.seg[seg].base;

        if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_BASE))
                *p = vmcs_readl(kvm_vmx_segment_fields[seg].base);
        return *p;
}

static u32 vmx_read_guest_seg_limit(struct vcpu_vmx *vmx, unsigned seg)
{
        u32 *p = &vmx->segment_cache.seg[seg].limit;

        if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_LIMIT))
                *p = vmcs_read32(kvm_vmx_segment_fields[seg].limit);
        return *p;
}

static u32 vmx_read_guest_seg_ar(struct vcpu_vmx *vmx, unsigned seg)
{
        u32 *p = &vmx->segment_cache.seg[seg].ar;

        if (!vmx_segment_cache_test_set(vmx, seg, SEG_FIELD_AR))
                *p = vmcs_read32(kvm_vmx_segment_fields[seg].ar_bytes);
        return *p;
}

void update_exception_bitmap(struct kvm_vcpu *vcpu)
{
        u32 eb;

        eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR) |
             (1u << DB_VECTOR) | (1u << AC_VECTOR);
        /*
         * Guest access to VMware backdoor ports could legitimately
         * trigger #GP because of TSS I/O permission bitmap.
         * We intercept those #GP and allow access to them anyway
         * as VMware does.
         */
        if (enable_vmware_backdoor)
                eb |= (1u << GP_VECTOR);
        if ((vcpu->guest_debug &
             (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP)) ==
            (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP))
                eb |= 1u << BP_VECTOR;
        if (to_vmx(vcpu)->rmode.vm86_active)
                eb = ~0;
        if (!vmx_need_pf_intercept(vcpu))
                eb &= ~(1u << PF_VECTOR);

        /* When we are running a nested L2 guest and L1 specified for it a
         * certain exception bitmap, we must trap the same exceptions and pass
         * them to L1. When running L2, we will only handle the exceptions
         * specified above if L1 did not want them.
         */
        if (is_guest_mode(vcpu))
                eb |= get_vmcs12(vcpu)->exception_bitmap;

        vmcs_write32(EXCEPTION_BITMAP, eb);
}

/*
 * Check if MSR is intercepted for currently loaded MSR bitmap.
 */
static bool msr_write_intercepted(struct kvm_vcpu *vcpu, u32 msr)
{
        unsigned long *msr_bitmap;
        int f = sizeof(unsigned long);

        if (!cpu_has_vmx_msr_bitmap())
                return true;

        msr_bitmap = to_vmx(vcpu)->loaded_vmcs->msr_bitmap;

        if (msr <= 0x1fff) {
                return !!test_bit(msr, msr_bitmap + 0x800 / f);
        } else if ((msr >= 0xc0000000) && (msr <= 0xc0001fff)) {
                msr &= 0x1fff;
                return !!test_bit(msr, msr_bitmap + 0xc00 / f);
        }

        return true;
}

static void clear_atomic_switch_msr_special(struct vcpu_vmx *vmx,
                unsigned long entry, unsigned long exit)
{
        vm_entry_controls_clearbit(vmx, entry);
        vm_exit_controls_clearbit(vmx, exit);
}

int vmx_find_loadstore_msr_slot(struct vmx_msrs *m, u32 msr)
{
        unsigned int i;

        for (i = 0; i < m->nr; ++i) {
                if (m->val[i].index == msr)
                        return i;
        }
        return -ENOENT;
}

static void clear_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr)
{
        int i;
        struct msr_autoload *m = &vmx->msr_autoload;

        switch (msr) {
        case MSR_EFER:
                if (cpu_has_load_ia32_efer()) {
                        clear_atomic_switch_msr_special(vmx,
                                        VM_ENTRY_LOAD_IA32_EFER,
                                        VM_EXIT_LOAD_IA32_EFER);
                        return;
                }
                break;
        case MSR_CORE_PERF_GLOBAL_CTRL:
                if (cpu_has_load_perf_global_ctrl()) {
                        clear_atomic_switch_msr_special(vmx,
                                        VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL,
                                        VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL);
                        return;
                }
                break;
        }
        i = vmx_find_loadstore_msr_slot(&m->guest, msr);
        if (i < 0)
                goto skip_guest;
        --m->guest.nr;
        m->guest.val[i] = m->guest.val[m->guest.nr];
        vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->guest.nr);

skip_guest:
        i = vmx_find_loadstore_msr_slot(&m->host, msr);
        if (i < 0)
                return;

        --m->host.nr;
        m->host.val[i] = m->host.val[m->host.nr];
        vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->host.nr);
}

static void add_atomic_switch_msr_special(struct vcpu_vmx *vmx,
                unsigned long entry, unsigned long exit,
                unsigned long guest_val_vmcs, unsigned long host_val_vmcs,
                u64 guest_val, u64 host_val)
{
        vmcs_write64(guest_val_vmcs, guest_val);
        if (host_val_vmcs != HOST_IA32_EFER)
                vmcs_write64(host_val_vmcs, host_val);
        vm_entry_controls_setbit(vmx, entry);
        vm_exit_controls_setbit(vmx, exit);
}

static void add_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr,
                                  u64 guest_val, u64 host_val, bool entry_only)
{
        int i, j = 0;
        struct msr_autoload *m = &vmx->msr_autoload;

        switch (msr) {
        case MSR_EFER:
                if (cpu_has_load_ia32_efer()) {
                        add_atomic_switch_msr_special(vmx,
                                        VM_ENTRY_LOAD_IA32_EFER,
                                        VM_EXIT_LOAD_IA32_EFER,
                                        GUEST_IA32_EFER,
                                        HOST_IA32_EFER,
                                        guest_val, host_val);
                        return;
                }
                break;
        case MSR_CORE_PERF_GLOBAL_CTRL:
                if (cpu_has_load_perf_global_ctrl()) {
                        add_atomic_switch_msr_special(vmx,
                                        VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL,
                                        VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL,
                                        GUEST_IA32_PERF_GLOBAL_CTRL,
                                        HOST_IA32_PERF_GLOBAL_CTRL,
                                        guest_val, host_val);
                        return;
                }
                break;
        case MSR_IA32_PEBS_ENABLE:
                /* PEBS needs a quiescent period after being disabled (to write
                 * a record).  Disabling PEBS through VMX MSR swapping doesn't
                 * provide that period, so a CPU could write host's record into
                 * guest's memory.
                 */
                wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
        }

        i = vmx_find_loadstore_msr_slot(&m->guest, msr);
        if (!entry_only)
                j = vmx_find_loadstore_msr_slot(&m->host, msr);

        if ((i < 0 && m->guest.nr == MAX_NR_LOADSTORE_MSRS) ||
            (j < 0 &&  m->host.nr == MAX_NR_LOADSTORE_MSRS)) {
                printk_once(KERN_WARNING "Not enough msr switch entries. "
                                "Can't add msr %x\n", msr);
                return;
        }
        if (i < 0) {
                i = m->guest.nr++;
                vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, m->guest.nr);
        }
        m->guest.val[i].index = msr;
        m->guest.val[i].value = guest_val;

        if (entry_only)
                return;

        if (j < 0) {
                j = m->host.nr++;
                vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, m->host.nr);
        }
        m->host.val[j].index = msr;
        m->host.val[j].value = host_val;
}

static bool update_transition_efer(struct vcpu_vmx *vmx, int efer_offset)
{
        u64 guest_efer = vmx->vcpu.arch.efer;
        u64 ignore_bits = 0;

        /* Shadow paging assumes NX to be available.  */
        if (!enable_ept)
                guest_efer |= EFER_NX;

        /*
         * LMA and LME handled by hardware; SCE meaningless outside long mode.
         */
        ignore_bits |= EFER_SCE;
#ifdef CONFIG_X86_64
        ignore_bits |= EFER_LMA | EFER_LME;
        /* SCE is meaningful only in long mode on Intel */
        if (guest_efer & EFER_LMA)
                ignore_bits &= ~(u64)EFER_SCE;
#endif

        /*
         * On EPT, we can't emulate NX, so we must switch EFER atomically.
         * On CPUs that support "load IA32_EFER", always switch EFER
         * atomically, since it's faster than switching it manually.
         */
        if (cpu_has_load_ia32_efer() ||
            (enable_ept && ((vmx->vcpu.arch.efer ^ host_efer) & EFER_NX))) {
                if (!(guest_efer & EFER_LMA))
                        guest_efer &= ~EFER_LME;
                if (guest_efer != host_efer)
                        add_atomic_switch_msr(vmx, MSR_EFER,
                                              guest_efer, host_efer, false);
                else
                        clear_atomic_switch_msr(vmx, MSR_EFER);
                return false;
        } else {
                clear_atomic_switch_msr(vmx, MSR_EFER);

                guest_efer &= ~ignore_bits;
                guest_efer |= host_efer & ignore_bits;

                vmx->guest_uret_msrs[efer_offset].data = guest_efer;
                vmx->guest_uret_msrs[efer_offset].mask = ~ignore_bits;

                return true;
        }
}

#ifdef CONFIG_X86_32
/*
 * On 32-bit kernels, VM exits still load the FS and GS bases from the
 * VMCS rather than the segment table.  KVM uses this helper to figure
 * out the current bases to poke them into the VMCS before entry.
 */
static unsigned long segment_base(u16 selector)
{
        struct desc_struct *table;
        unsigned long v;

        if (!(selector & ~SEGMENT_RPL_MASK))
                return 0;

        table = get_current_gdt_ro();

        if ((selector & SEGMENT_TI_MASK) == SEGMENT_LDT) {
                u16 ldt_selector = kvm_read_ldt();

                if (!(ldt_selector & ~SEGMENT_RPL_MASK))
                        return 0;

                table = (struct desc_struct *)segment_base(ldt_selector);
        }
        v = get_desc_base(&table[selector >> 3]);
        return v;
}
#endif

static inline bool pt_can_write_msr(struct vcpu_vmx *vmx)
{
        return vmx_pt_mode_is_host_guest() &&
               !(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN);
}

static inline bool pt_output_base_valid(struct kvm_vcpu *vcpu, u64 base)
{
        /* The base must be 128-byte aligned and a legal physical address. */
        return !kvm_vcpu_is_illegal_gpa(vcpu, base) && !(base & 0x7f);
}

static inline void pt_load_msr(struct pt_ctx *ctx, u32 addr_range)
{
        u32 i;

        wrmsrl(MSR_IA32_RTIT_STATUS, ctx->status);
        wrmsrl(MSR_IA32_RTIT_OUTPUT_BASE, ctx->output_base);
        wrmsrl(MSR_IA32_RTIT_OUTPUT_MASK, ctx->output_mask);
        wrmsrl(MSR_IA32_RTIT_CR3_MATCH, ctx->cr3_match);
        for (i = 0; i < addr_range; i++) {
                wrmsrl(MSR_IA32_RTIT_ADDR0_A + i * 2, ctx->addr_a[i]);
                wrmsrl(MSR_IA32_RTIT_ADDR0_B + i * 2, ctx->addr_b[i]);
        }
}

static inline void pt_save_msr(struct pt_ctx *ctx, u32 addr_range)
{
        u32 i;

        rdmsrl(MSR_IA32_RTIT_STATUS, ctx->status);
        rdmsrl(MSR_IA32_RTIT_OUTPUT_BASE, ctx->output_base);
        rdmsrl(MSR_IA32_RTIT_OUTPUT_MASK, ctx->output_mask);
        rdmsrl(MSR_IA32_RTIT_CR3_MATCH, ctx->cr3_match);
        for (i = 0; i < addr_range; i++) {
                rdmsrl(MSR_IA32_RTIT_ADDR0_A + i * 2, ctx->addr_a[i]);
                rdmsrl(MSR_IA32_RTIT_ADDR0_B + i * 2, ctx->addr_b[i]);
        }
}

static void pt_guest_enter(struct vcpu_vmx *vmx)
{
        if (vmx_pt_mode_is_system())
                return;

        /*
         * GUEST_IA32_RTIT_CTL is already set in the VMCS.
         * Save host state before VM entry.
         */
        rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
        if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
                wrmsrl(MSR_IA32_RTIT_CTL, 0);
                pt_save_msr(&vmx->pt_desc.host, vmx->pt_desc.addr_range);
                pt_load_msr(&vmx->pt_desc.guest, vmx->pt_desc.addr_range);
        }
}

static void pt_guest_exit(struct vcpu_vmx *vmx)
{
        if (vmx_pt_mode_is_system())
                return;

        if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
                pt_save_msr(&vmx->pt_desc.guest, vmx->pt_desc.addr_range);
                pt_load_msr(&vmx->pt_desc.host, vmx->pt_desc.addr_range);
        }

        /* Reload host state (IA32_RTIT_CTL will be cleared on VM exit). */
        wrmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
}

void vmx_set_host_fs_gs(struct vmcs_host_state *host, u16 fs_sel, u16 gs_sel,
                        unsigned long fs_base, unsigned long gs_base)
{
        if (unlikely(fs_sel != host->fs_sel)) {
                if (!(fs_sel & 7))
                        vmcs_write16(HOST_FS_SELECTOR, fs_sel);
                else
                        vmcs_write16(HOST_FS_SELECTOR, 0);
                host->fs_sel = fs_sel;
        }
        if (unlikely(gs_sel != host->gs_sel)) {
                if (!(gs_sel & 7))
                        vmcs_write16(HOST_GS_SELECTOR, gs_sel);
                else
                        vmcs_write16(HOST_GS_SELECTOR, 0);
                host->gs_sel = gs_sel;
        }
        if (unlikely(fs_base != host->fs_base)) {
                vmcs_writel(HOST_FS_BASE, fs_base);
                host->fs_base = fs_base;
        }
        if (unlikely(gs_base != host->gs_base)) {
                vmcs_writel(HOST_GS_BASE, gs_base);
                host->gs_base = gs_base;
        }
}

void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct vmcs_host_state *host_state;
#ifdef CONFIG_X86_64
        int cpu = raw_smp_processor_id();
#endif
        unsigned long fs_base, gs_base;
        u16 fs_sel, gs_sel;
        int i;

        vmx->req_immediate_exit = false;

        /*
         * Note that guest MSRs to be saved/restored can also be changed
         * when guest state is loaded. This happens when guest transitions
         * to/from long-mode by setting MSR_EFER.LMA.
         */
        if (!vmx->guest_uret_msrs_loaded) {
                vmx->guest_uret_msrs_loaded = true;
                for (i = 0; i < vmx->nr_active_uret_msrs; ++i)
                        kvm_set_user_return_msr(vmx->guest_uret_msrs[i].index,
                                                vmx->guest_uret_msrs[i].data,
                                                vmx->guest_uret_msrs[i].mask);

        }

        if (vmx->nested.need_vmcs12_to_shadow_sync)
                nested_sync_vmcs12_to_shadow(vcpu);

        if (vmx->guest_state_loaded)
                return;

        host_state = &vmx->loaded_vmcs->host_state;

        /*
         * Set host fs and gs selectors.  Unfortunately, 22.2.3 does not
         * allow segment selectors with cpl > 0 or ti == 1.
         */
        host_state->ldt_sel = kvm_read_ldt();

#ifdef CONFIG_X86_64
        savesegment(ds, host_state->ds_sel);
        savesegment(es, host_state->es_sel);

        gs_base = cpu_kernelmode_gs_base(cpu);
        if (likely(is_64bit_mm(current->mm))) {
                current_save_fsgs();
                fs_sel = current->thread.fsindex;
                gs_sel = current->thread.gsindex;
                fs_base = current->thread.fsbase;
                vmx->msr_host_kernel_gs_base = current->thread.gsbase;
        } else {
                savesegment(fs, fs_sel);
                savesegment(gs, gs_sel);
                fs_base = read_msr(MSR_FS_BASE);
                vmx->msr_host_kernel_gs_base = read_msr(MSR_KERNEL_GS_BASE);
        }

        wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
#else
        savesegment(fs, fs_sel);
        savesegment(gs, gs_sel);
        fs_base = segment_base(fs_sel);
        gs_base = segment_base(gs_sel);
#endif

        vmx_set_host_fs_gs(host_state, fs_sel, gs_sel, fs_base, gs_base);
        vmx->guest_state_loaded = true;
}

static void vmx_prepare_switch_to_host(struct vcpu_vmx *vmx)
{
        struct vmcs_host_state *host_state;

        if (!vmx->guest_state_loaded)
                return;

        host_state = &vmx->loaded_vmcs->host_state;

        ++vmx->vcpu.stat.host_state_reload;

#ifdef CONFIG_X86_64
        rdmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
#endif
        if (host_state->ldt_sel || (host_state->gs_sel & 7)) {
                kvm_load_ldt(host_state->ldt_sel);
#ifdef CONFIG_X86_64
                load_gs_index(host_state->gs_sel);
#else
                loadsegment(gs, host_state->gs_sel);
#endif
        }
        if (host_state->fs_sel & 7)
                loadsegment(fs, host_state->fs_sel);
#ifdef CONFIG_X86_64
        if (unlikely(host_state->ds_sel | host_state->es_sel)) {
                loadsegment(ds, host_state->ds_sel);
                loadsegment(es, host_state->es_sel);
        }
#endif
        invalidate_tss_limit();
#ifdef CONFIG_X86_64
        wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_host_kernel_gs_base);
#endif
        load_fixmap_gdt(raw_smp_processor_id());
        vmx->guest_state_loaded = false;
        vmx->guest_uret_msrs_loaded = false;
}

#ifdef CONFIG_X86_64
static u64 vmx_read_guest_kernel_gs_base(struct vcpu_vmx *vmx)
{
        preempt_disable();
        if (vmx->guest_state_loaded)
                rdmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
        preempt_enable();
        return vmx->msr_guest_kernel_gs_base;
}

static void vmx_write_guest_kernel_gs_base(struct vcpu_vmx *vmx, u64 data)
{
        preempt_disable();
        if (vmx->guest_state_loaded)
                wrmsrl(MSR_KERNEL_GS_BASE, data);
        preempt_enable();
        vmx->msr_guest_kernel_gs_base = data;
}
#endif

void vmx_vcpu_load_vmcs(struct kvm_vcpu *vcpu, int cpu,
                        struct loaded_vmcs *buddy)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        bool already_loaded = vmx->loaded_vmcs->cpu == cpu;
        struct vmcs *prev;

        if (!already_loaded) {
                loaded_vmcs_clear(vmx->loaded_vmcs);
                local_irq_disable();

                /*
                 * Ensure loaded_vmcs->cpu is read before adding loaded_vmcs to
                 * this cpu's percpu list, otherwise it may not yet be deleted
                 * from its previous cpu's percpu list.  Pairs with the
                 * smb_wmb() in __loaded_vmcs_clear().
                 */
                smp_rmb();

                list_add(&vmx->loaded_vmcs->loaded_vmcss_on_cpu_link,
                         &per_cpu(loaded_vmcss_on_cpu, cpu));
                local_irq_enable();
        }

        prev = per_cpu(current_vmcs, cpu);
        if (prev != vmx->loaded_vmcs->vmcs) {
                per_cpu(current_vmcs, cpu) = vmx->loaded_vmcs->vmcs;
                vmcs_load(vmx->loaded_vmcs->vmcs);

                /*
                 * No indirect branch prediction barrier needed when switching
                 * the active VMCS within a guest, e.g. on nested VM-Enter.
                 * The L1 VMM can protect itself with retpolines, IBPB or IBRS.
                 */
                if (!buddy || WARN_ON_ONCE(buddy->vmcs != prev))
                        indirect_branch_prediction_barrier();
        }

        if (!already_loaded) {
                void *gdt = get_current_gdt_ro();
                unsigned long sysenter_esp;

                /*
                 * Flush all EPTP/VPID contexts, the new pCPU may have stale
                 * TLB entries from its previous association with the vCPU.
                 */
                kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);

                /*
                 * Linux uses per-cpu TSS and GDT, so set these when switching
                 * processors.  See 22.2.4.
                 */
                vmcs_writel(HOST_TR_BASE,
                            (unsigned long)&get_cpu_entry_area(cpu)->tss.x86_tss);
                vmcs_writel(HOST_GDTR_BASE, (unsigned long)gdt);   /* 22.2.4 */

                rdmsrl(MSR_IA32_SYSENTER_ESP, sysenter_esp);
                vmcs_writel(HOST_IA32_SYSENTER_ESP, sysenter_esp); /* 22.2.3 */

                vmx->loaded_vmcs->cpu = cpu;
        }

        /* Setup TSC multiplier */
        if (kvm_has_tsc_control &&
            vmx->current_tsc_ratio != vcpu->arch.tsc_scaling_ratio)
                decache_tsc_multiplier(vmx);
}

/*
 * Switches to specified vcpu, until a matching vcpu_put(), but assumes
 * vcpu mutex is already taken.
 */
static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        vmx_vcpu_load_vmcs(vcpu, cpu, NULL);

        vmx_vcpu_pi_load(vcpu, cpu);

        vmx->host_debugctlmsr = get_debugctlmsr();
}

static void vmx_vcpu_put(struct kvm_vcpu *vcpu)
{
        vmx_vcpu_pi_put(vcpu);

        vmx_prepare_switch_to_host(to_vmx(vcpu));
}

static bool emulation_required(struct kvm_vcpu *vcpu)
{
        return emulate_invalid_guest_state && !vmx_guest_state_valid(vcpu);
}

unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long rflags, save_rflags;

        if (!kvm_register_is_available(vcpu, VCPU_EXREG_RFLAGS)) {
                kvm_register_mark_available(vcpu, VCPU_EXREG_RFLAGS);
                rflags = vmcs_readl(GUEST_RFLAGS);
                if (vmx->rmode.vm86_active) {
                        rflags &= RMODE_GUEST_OWNED_EFLAGS_BITS;
                        save_rflags = vmx->rmode.save_rflags;
                        rflags |= save_rflags & ~RMODE_GUEST_OWNED_EFLAGS_BITS;
                }
                vmx->rflags = rflags;
        }
        return vmx->rflags;
}

void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long old_rflags;

        if (is_unrestricted_guest(vcpu)) {
                kvm_register_mark_available(vcpu, VCPU_EXREG_RFLAGS);
                vmx->rflags = rflags;
                vmcs_writel(GUEST_RFLAGS, rflags);
                return;
        }

        old_rflags = vmx_get_rflags(vcpu);
        vmx->rflags = rflags;
        if (vmx->rmode.vm86_active) {
                vmx->rmode.save_rflags = rflags;
                rflags |= X86_EFLAGS_IOPL | X86_EFLAGS_VM;
        }
        vmcs_writel(GUEST_RFLAGS, rflags);

        if ((old_rflags ^ vmx->rflags) & X86_EFLAGS_VM)
                vmx->emulation_required = emulation_required(vcpu);
}

u32 vmx_get_interrupt_shadow(struct kvm_vcpu *vcpu)
{
        u32 interruptibility = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
        int ret = 0;

        if (interruptibility & GUEST_INTR_STATE_STI)
                ret |= KVM_X86_SHADOW_INT_STI;
        if (interruptibility & GUEST_INTR_STATE_MOV_SS)
                ret |= KVM_X86_SHADOW_INT_MOV_SS;

        return ret;
}

void vmx_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask)
{
        u32 interruptibility_old = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
        u32 interruptibility = interruptibility_old;

        interruptibility &= ~(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS);

        if (mask & KVM_X86_SHADOW_INT_MOV_SS)
                interruptibility |= GUEST_INTR_STATE_MOV_SS;
        else if (mask & KVM_X86_SHADOW_INT_STI)
                interruptibility |= GUEST_INTR_STATE_STI;

        if ((interruptibility != interruptibility_old))
                vmcs_write32(GUEST_INTERRUPTIBILITY_INFO, interruptibility);
}

static int vmx_rtit_ctl_check(struct kvm_vcpu *vcpu, u64 data)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long value;

        /*
         * Any MSR write that attempts to change bits marked reserved will
         * case a #GP fault.
         */
        if (data & vmx->pt_desc.ctl_bitmask)
                return 1;

        /*
         * Any attempt to modify IA32_RTIT_CTL while TraceEn is set will
         * result in a #GP unless the same write also clears TraceEn.
         */
        if ((vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) &&
                ((vmx->pt_desc.guest.ctl ^ data) & ~RTIT_CTL_TRACEEN))
                return 1;

        /*
         * WRMSR to IA32_RTIT_CTL that sets TraceEn but clears this bit
         * and FabricEn would cause #GP, if
         * CPUID.(EAX=14H, ECX=0):ECX.SNGLRGNOUT[bit 2] = 0
         */
        if ((data & RTIT_CTL_TRACEEN) && !(data & RTIT_CTL_TOPA) &&
                !(data & RTIT_CTL_FABRIC_EN) &&
                !intel_pt_validate_cap(vmx->pt_desc.caps,
                                        PT_CAP_single_range_output))
                return 1;

        /*
         * MTCFreq, CycThresh and PSBFreq encodings check, any MSR write that
         * utilize encodings marked reserved will casue a #GP fault.
         */
        value = intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_mtc_periods);
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_mtc) &&
                        !test_bit((data & RTIT_CTL_MTC_RANGE) >>
                        RTIT_CTL_MTC_RANGE_OFFSET, &value))
                return 1;
        value = intel_pt_validate_cap(vmx->pt_desc.caps,
                                                PT_CAP_cycle_thresholds);
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_cyc) &&
                        !test_bit((data & RTIT_CTL_CYC_THRESH) >>
                        RTIT_CTL_CYC_THRESH_OFFSET, &value))
                return 1;
        value = intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_periods);
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_cyc) &&
                        !test_bit((data & RTIT_CTL_PSB_FREQ) >>
                        RTIT_CTL_PSB_FREQ_OFFSET, &value))
                return 1;

        /*
         * If ADDRx_CFG is reserved or the encodings is >2 will
         * cause a #GP fault.
         */
        value = (data & RTIT_CTL_ADDR0) >> RTIT_CTL_ADDR0_OFFSET;
        if ((value && (vmx->pt_desc.addr_range < 1)) || (value > 2))
                return 1;
        value = (data & RTIT_CTL_ADDR1) >> RTIT_CTL_ADDR1_OFFSET;
        if ((value && (vmx->pt_desc.addr_range < 2)) || (value > 2))
                return 1;
        value = (data & RTIT_CTL_ADDR2) >> RTIT_CTL_ADDR2_OFFSET;
        if ((value && (vmx->pt_desc.addr_range < 3)) || (value > 2))
                return 1;
        value = (data & RTIT_CTL_ADDR3) >> RTIT_CTL_ADDR3_OFFSET;
        if ((value && (vmx->pt_desc.addr_range < 4)) || (value > 2))
                return 1;

        return 0;
}

static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, void *insn, int insn_len)
{
        return true;
}

static int skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
        unsigned long rip, orig_rip;

        /*
         * Using VMCS.VM_EXIT_INSTRUCTION_LEN on EPT misconfig depends on
         * undefined behavior: Intel's SDM doesn't mandate the VMCS field be
         * set when EPT misconfig occurs.  In practice, real hardware updates
         * VM_EXIT_INSTRUCTION_LEN on EPT misconfig, but other hypervisors
         * (namely Hyper-V) don't set it due to it being undefined behavior,
         * i.e. we end up advancing IP with some random value.
         */
        if (!static_cpu_has(X86_FEATURE_HYPERVISOR) ||
            to_vmx(vcpu)->exit_reason != EXIT_REASON_EPT_MISCONFIG) {
                orig_rip = kvm_rip_read(vcpu);
                rip = orig_rip + vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
#ifdef CONFIG_X86_64
                /*
                 * We need to mask out the high 32 bits of RIP if not in 64-bit
                 * mode, but just finding out that we are in 64-bit mode is
                 * quite expensive.  Only do it if there was a carry.
                 */
                if (unlikely(((rip ^ orig_rip) >> 31) == 3) && !is_64_bit_mode(vcpu))
                        rip = (u32)rip;
#endif
                kvm_rip_write(vcpu, rip);
        } else {
                if (!kvm_emulate_instruction(vcpu, EMULTYPE_SKIP))
                        return 0;
        }

        /* skipping an emulated instruction also counts */
        vmx_set_interrupt_shadow(vcpu, 0);

        return 1;
}

/*
 * Recognizes a pending MTF VM-exit and records the nested state for later
 * delivery.
 */
static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu)
{
        struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (!is_guest_mode(vcpu))
                return;

        /*
         * Per the SDM, MTF takes priority over debug-trap exceptions besides
         * T-bit traps. As instruction emulation is completed (i.e. at the
         * instruction boundary), any #DB exception pending delivery must be a
         * debug-trap. Record the pending MTF state to be delivered in
         * vmx_check_nested_events().
         */
        if (nested_cpu_has_mtf(vmcs12) &&
            (!vcpu->arch.exception.pending ||
             vcpu->arch.exception.nr == DB_VECTOR))
                vmx->nested.mtf_pending = true;
        else
                vmx->nested.mtf_pending = false;
}

static int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
        vmx_update_emulated_instruction(vcpu);
        return skip_emulated_instruction(vcpu);
}

static void vmx_clear_hlt(struct kvm_vcpu *vcpu)
{
        /*
         * Ensure that we clear the HLT state in the VMCS.  We don't need to
         * explicitly skip the instruction because if the HLT state is set,
         * then the instruction is already executing and RIP has already been
         * advanced.
         */
        if (kvm_hlt_in_guest(vcpu->kvm) &&
                        vmcs_read32(GUEST_ACTIVITY_STATE) == GUEST_ACTIVITY_HLT)
                vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE);
}

static void vmx_queue_exception(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned nr = vcpu->arch.exception.nr;
        bool has_error_code = vcpu->arch.exception.has_error_code;
        u32 error_code = vcpu->arch.exception.error_code;
        u32 intr_info = nr | INTR_INFO_VALID_MASK;

        kvm_deliver_exception_payload(vcpu);

        if (has_error_code) {
                vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE, error_code);
                intr_info |= INTR_INFO_DELIVER_CODE_MASK;
        }

        if (vmx->rmode.vm86_active) {
                int inc_eip = 0;
                if (kvm_exception_is_soft(nr))
                        inc_eip = vcpu->arch.event_exit_inst_len;
                kvm_inject_realmode_interrupt(vcpu, nr, inc_eip);
                return;
        }

        WARN_ON_ONCE(vmx->emulation_required);

        if (kvm_exception_is_soft(nr)) {
                vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
                             vmx->vcpu.arch.event_exit_inst_len);
                intr_info |= INTR_TYPE_SOFT_EXCEPTION;
        } else
                intr_info |= INTR_TYPE_HARD_EXCEPTION;

        vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, intr_info);

        vmx_clear_hlt(vcpu);
}

/*
 * Swap MSR entry in host/guest MSR entry array.
 */
static void move_msr_up(struct vcpu_vmx *vmx, int from, int to)
{
        struct vmx_uret_msr tmp;

        tmp = vmx->guest_uret_msrs[to];
        vmx->guest_uret_msrs[to] = vmx->guest_uret_msrs[from];
        vmx->guest_uret_msrs[from] = tmp;
}

/*
 * Set up the vmcs to automatically save and restore system
 * msrs.  Don't touch the 64-bit msrs if the guest is in legacy
 * mode, as fiddling with msrs is very expensive.
 */
static void setup_msrs(struct vcpu_vmx *vmx)
{
        int nr_active_uret_msrs, index;

        nr_active_uret_msrs = 0;
#ifdef CONFIG_X86_64
        /*
         * The SYSCALL MSRs are only needed on long mode guests, and only
         * when EFER.SCE is set.
         */
        if (is_long_mode(&vmx->vcpu) && (vmx->vcpu.arch.efer & EFER_SCE)) {
                index = __find_msr_index(vmx, MSR_STAR);
                if (index >= 0)
                        move_msr_up(vmx, index, nr_active_uret_msrs++);
                index = __find_msr_index(vmx, MSR_LSTAR);
                if (index >= 0)
                        move_msr_up(vmx, index, nr_active_uret_msrs++);
                index = __find_msr_index(vmx, MSR_SYSCALL_MASK);
                if (index >= 0)
                        move_msr_up(vmx, index, nr_active_uret_msrs++);
        }
#endif
        index = __find_msr_index(vmx, MSR_EFER);
        if (index >= 0 && update_transition_efer(vmx, index))
                move_msr_up(vmx, index, nr_active_uret_msrs++);
        index = __find_msr_index(vmx, MSR_TSC_AUX);
        if (index >= 0 && guest_cpuid_has(&vmx->vcpu, X86_FEATURE_RDTSCP))
                move_msr_up(vmx, index, nr_active_uret_msrs++);
        index = __find_msr_index(vmx, MSR_IA32_TSX_CTRL);
        if (index >= 0)
                move_msr_up(vmx, index, nr_active_uret_msrs++);

        vmx->nr_active_uret_msrs = nr_active_uret_msrs;
        vmx->guest_uret_msrs_loaded = false;

        if (cpu_has_vmx_msr_bitmap())
                vmx_update_msr_bitmap(&vmx->vcpu);
}

static u64 vmx_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
        struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
        u64 g_tsc_offset = 0;

        /*
         * We're here if L1 chose not to trap WRMSR to TSC. According
         * to the spec, this should set L1's TSC; The offset that L1
         * set for L2 remains unchanged, and still needs to be added
         * to the newly set TSC to get L2's TSC.
         */
        if (is_guest_mode(vcpu) &&
            (vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_TSC_OFFSETTING))
                g_tsc_offset = vmcs12->tsc_offset;

        trace_kvm_write_tsc_offset(vcpu->vcpu_id,
                                   vcpu->arch.tsc_offset - g_tsc_offset,
                                   offset);
        vmcs_write64(TSC_OFFSET, offset + g_tsc_offset);
        return offset + g_tsc_offset;
}

/*
 * nested_vmx_allowed() checks whether a guest should be allowed to use VMX
 * instructions and MSRs (i.e., nested VMX). Nested VMX is disabled for
 * all guests if the "nested" module option is off, and can also be disabled
 * for a single guest by disabling its VMX cpuid bit.
 */
bool nested_vmx_allowed(struct kvm_vcpu *vcpu)
{
        return nested && guest_cpuid_has(vcpu, X86_FEATURE_VMX);
}

static inline bool vmx_feature_control_msr_valid(struct kvm_vcpu *vcpu,
                                                 uint64_t val)
{
        uint64_t valid_bits = to_vmx(vcpu)->msr_ia32_feature_control_valid_bits;

        return !(val & ~valid_bits);
}

static int vmx_get_msr_feature(struct kvm_msr_entry *msr)
{
        switch (msr->index) {
        case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
                if (!nested)
                        return 1;
                return vmx_get_vmx_msr(&vmcs_config.nested, msr->index, &msr->data);
        case MSR_IA32_PERF_CAPABILITIES:
                msr->data = vmx_get_perf_capabilities();
                return 0;
        default:
                return KVM_MSR_RET_INVALID;
        }
}

/*
 * Reads an msr value (of 'msr_index') into 'pdata'.
 * Returns 0 on success, non-0 otherwise.
 * Assumes vcpu_load() was already called.
 */
static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct vmx_uret_msr *msr;
        u32 index;

        switch (msr_info->index) {
#ifdef CONFIG_X86_64
        case MSR_FS_BASE:
                msr_info->data = vmcs_readl(GUEST_FS_BASE);
                break;
        case MSR_GS_BASE:
                msr_info->data = vmcs_readl(GUEST_GS_BASE);
                break;
        case MSR_KERNEL_GS_BASE:
                msr_info->data = vmx_read_guest_kernel_gs_base(vmx);
                break;
#endif
        case MSR_EFER:
                return kvm_get_msr_common(vcpu, msr_info);
        case MSR_IA32_TSX_CTRL:
                if (!msr_info->host_initiated &&
                    !(vcpu->arch.arch_capabilities & ARCH_CAP_TSX_CTRL_MSR))
                        return 1;
                goto find_uret_msr;
        case MSR_IA32_UMWAIT_CONTROL:
                if (!msr_info->host_initiated && !vmx_has_waitpkg(vmx))
                        return 1;

                msr_info->data = vmx->msr_ia32_umwait_control;
                break;
        case MSR_IA32_SPEC_CTRL:
                if (!msr_info->host_initiated &&
                    !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL))
                        return 1;

                msr_info->data = to_vmx(vcpu)->spec_ctrl;
                break;
        case MSR_IA32_SYSENTER_CS:
                msr_info->data = vmcs_read32(GUEST_SYSENTER_CS);
                break;
        case MSR_IA32_SYSENTER_EIP:
                msr_info->data = vmcs_readl(GUEST_SYSENTER_EIP);
                break;
        case MSR_IA32_SYSENTER_ESP:
                msr_info->data = vmcs_readl(GUEST_SYSENTER_ESP);
                break;
        case MSR_IA32_BNDCFGS:
                if (!kvm_mpx_supported() ||
                    (!msr_info->host_initiated &&
                     !guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
                        return 1;
                msr_info->data = vmcs_read64(GUEST_BNDCFGS);
                break;
        case MSR_IA32_MCG_EXT_CTL:
                if (!msr_info->host_initiated &&
                    !(vmx->msr_ia32_feature_control &
                      FEAT_CTL_LMCE_ENABLED))
                        return 1;
                msr_info->data = vcpu->arch.mcg_ext_ctl;
                break;
        case MSR_IA32_FEAT_CTL:
                msr_info->data = vmx->msr_ia32_feature_control;
                break;
        case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
                if (!nested_vmx_allowed(vcpu))
                        return 1;
                if (vmx_get_vmx_msr(&vmx->nested.msrs, msr_info->index,
                                    &msr_info->data))
                        return 1;
                /*
                 * Enlightened VMCS v1 doesn't have certain fields, but buggy
                 * Hyper-V versions are still trying to use corresponding
                 * features when they are exposed. Filter out the essential
                 * minimum.
                 */
                if (!msr_info->host_initiated &&
                    vmx->nested.enlightened_vmcs_enabled)
                        nested_evmcs_filter_control_msr(msr_info->index,
                                                        &msr_info->data);
                break;
        case MSR_IA32_RTIT_CTL:
                if (!vmx_pt_mode_is_host_guest())
                        return 1;
                msr_info->data = vmx->pt_desc.guest.ctl;
                break;
        case MSR_IA32_RTIT_STATUS:
                if (!vmx_pt_mode_is_host_guest())
                        return 1;
                msr_info->data = vmx->pt_desc.guest.status;
                break;
        case MSR_IA32_RTIT_CR3_MATCH:
                if (!vmx_pt_mode_is_host_guest() ||
                        !intel_pt_validate_cap(vmx->pt_desc.caps,
                                                PT_CAP_cr3_filtering))
                        return 1;
                msr_info->data = vmx->pt_desc.guest.cr3_match;
                break;
        case MSR_IA32_RTIT_OUTPUT_BASE:
                if (!vmx_pt_mode_is_host_guest() ||
                        (!intel_pt_validate_cap(vmx->pt_desc.caps,
                                        PT_CAP_topa_output) &&
                         !intel_pt_validate_cap(vmx->pt_desc.caps,
                                        PT_CAP_single_range_output)))
                        return 1;
                msr_info->data = vmx->pt_desc.guest.output_base;
                break;
        case MSR_IA32_RTIT_OUTPUT_MASK:
                if (!vmx_pt_mode_is_host_guest() ||
                        (!intel_pt_validate_cap(vmx->pt_desc.caps,
                                        PT_CAP_topa_output) &&
                         !intel_pt_validate_cap(vmx->pt_desc.caps,
                                        PT_CAP_single_range_output)))
                        return 1;
                msr_info->data = vmx->pt_desc.guest.output_mask;
                break;
        case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
                index = msr_info->index - MSR_IA32_RTIT_ADDR0_A;
                if (!vmx_pt_mode_is_host_guest() ||
                        (index >= 2 * intel_pt_validate_cap(vmx->pt_desc.caps,
                                        PT_CAP_num_address_ranges)))
                        return 1;
                if (index % 2)
                        msr_info->data = vmx->pt_desc.guest.addr_b[index / 2];
                else
                        msr_info->data = vmx->pt_desc.guest.addr_a[index / 2];
                break;
        case MSR_TSC_AUX:
                if (!msr_info->host_initiated &&
                    !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
                        return 1;
                goto find_uret_msr;
        default:
        find_uret_msr:
                msr = find_msr_entry(vmx, msr_info->index);
                if (msr) {
                        msr_info->data = msr->data;
                        break;
                }
                return kvm_get_msr_common(vcpu, msr_info);
        }

        return 0;
}

static u64 nested_vmx_truncate_sysenter_addr(struct kvm_vcpu *vcpu,
                                                    u64 data)
{
#ifdef CONFIG_X86_64
        if (!guest_cpuid_has(vcpu, X86_FEATURE_LM))
                return (u32)data;
#endif
        return (unsigned long)data;
}

/*
 * Writes msr value into the appropriate "register".
 * Returns 0 on success, non-0 otherwise.
 * Assumes vcpu_load() was already called.
 */
static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct vmx_uret_msr *msr;
        int ret = 0;
        u32 msr_index = msr_info->index;
        u64 data = msr_info->data;
        u32 index;

        switch (msr_index) {
        case MSR_EFER:
                ret = kvm_set_msr_common(vcpu, msr_info);
                break;
#ifdef CONFIG_X86_64
        case MSR_FS_BASE:
                vmx_segment_cache_clear(vmx);
                vmcs_writel(GUEST_FS_BASE, data);
                break;
        case MSR_GS_BASE:
                vmx_segment_cache_clear(vmx);
                vmcs_writel(GUEST_GS_BASE, data);
                break;
        case MSR_KERNEL_GS_BASE:
                vmx_write_guest_kernel_gs_base(vmx, data);
                break;
#endif
        case MSR_IA32_SYSENTER_CS:
                if (is_guest_mode(vcpu))
                        get_vmcs12(vcpu)->guest_sysenter_cs = data;
                vmcs_write32(GUEST_SYSENTER_CS, data);
                break;
        case MSR_IA32_SYSENTER_EIP:
                if (is_guest_mode(vcpu)) {
                        data = nested_vmx_truncate_sysenter_addr(vcpu, data);
                        get_vmcs12(vcpu)->guest_sysenter_eip = data;
                }
                vmcs_writel(GUEST_SYSENTER_EIP, data);
                break;
        case MSR_IA32_SYSENTER_ESP:
                if (is_guest_mode(vcpu)) {
                        data = nested_vmx_truncate_sysenter_addr(vcpu, data);
                        get_vmcs12(vcpu)->guest_sysenter_esp = data;
                }
                vmcs_writel(GUEST_SYSENTER_ESP, data);
                break;
        case MSR_IA32_DEBUGCTLMSR:
                if (is_guest_mode(vcpu) && get_vmcs12(vcpu)->vm_exit_controls &
                                                VM_EXIT_SAVE_DEBUG_CONTROLS)
                        get_vmcs12(vcpu)->guest_ia32_debugctl = data;

                ret = kvm_set_msr_common(vcpu, msr_info);
                break;

        case MSR_IA32_BNDCFGS:
                if (!kvm_mpx_supported() ||
                    (!msr_info->host_initiated &&
                     !guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
                        return 1;
                if (is_noncanonical_address(data & PAGE_MASK, vcpu) ||
                    (data & MSR_IA32_BNDCFGS_RSVD))
                        return 1;
                vmcs_write64(GUEST_BNDCFGS, data);
                break;
        case MSR_IA32_UMWAIT_CONTROL:
                if (!msr_info->host_initiated && !vmx_has_waitpkg(vmx))
                        return 1;

                /* The reserved bit 1 and non-32 bit [63:32] should be zero */
                if (data & (BIT_ULL(1) | GENMASK_ULL(63, 32)))
                        return 1;

                vmx->msr_ia32_umwait_control = data;
                break;
        case MSR_IA32_SPEC_CTRL:
                if (!msr_info->host_initiated &&
                    !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL))
                        return 1;

                if (kvm_spec_ctrl_test_value(data))
                        return 1;

                vmx->spec_ctrl = data;
                if (!data)
                        break;

                /*
                 * For non-nested:
                 * When it's written (to non-zero) for the first time, pass
                 * it through.
                 *
                 * For nested:
                 * The handling of the MSR bitmap for L2 guests is done in
                 * nested_vmx_prepare_msr_bitmap. We should not touch the
                 * vmcs02.msr_bitmap here since it gets completely overwritten
                 * in the merging. We update the vmcs01 here for L1 as well
                 * since it will end up touching the MSR anyway now.
                 */
                vmx_disable_intercept_for_msr(vmx->vmcs01.msr_bitmap,
                                              MSR_IA32_SPEC_CTRL,
                                              MSR_TYPE_RW);
                break;
        case MSR_IA32_TSX_CTRL:
                if (!msr_info->host_initiated &&
                    !(vcpu->arch.arch_capabilities & ARCH_CAP_TSX_CTRL_MSR))
                        return 1;
                if (data & ~(TSX_CTRL_RTM_DISABLE | TSX_CTRL_CPUID_CLEAR))
                        return 1;
                goto find_uret_msr;
        case MSR_IA32_PRED_CMD:
                if (!msr_info->host_initiated &&
                    !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL))
                        return 1;

                if (data & ~PRED_CMD_IBPB)
                        return 1;
                if (!boot_cpu_has(X86_FEATURE_SPEC_CTRL))
                        return 1;
                if (!data)
                        break;

                wrmsrl(MSR_IA32_PRED_CMD, PRED_CMD_IBPB);

                /*
                 * For non-nested:
                 * When it's written (to non-zero) for the first time, pass
                 * it through.
                 *
                 * For nested:
                 * The handling of the MSR bitmap for L2 guests is done in
                 * nested_vmx_prepare_msr_bitmap. We should not touch the
                 * vmcs02.msr_bitmap here since it gets completely overwritten
                 * in the merging.
                 */
                vmx_disable_intercept_for_msr(vmx->vmcs01.msr_bitmap, MSR_IA32_PRED_CMD,
                                              MSR_TYPE_W);
                break;
        case MSR_IA32_CR_PAT:
                if (!kvm_pat_valid(data))
                        return 1;

                if (is_guest_mode(vcpu) &&
                    get_vmcs12(vcpu)->vm_exit_controls & VM_EXIT_SAVE_IA32_PAT)
                        get_vmcs12(vcpu)->guest_ia32_pat = data;

                if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) {
                        vmcs_write64(GUEST_IA32_PAT, data);
                        vcpu->arch.pat = data;
                        break;
                }
                ret = kvm_set_msr_common(vcpu, msr_info);
                break;
        case MSR_IA32_TSC_ADJUST:
                ret = kvm_set_msr_common(vcpu, msr_info);
                break;
        case MSR_IA32_MCG_EXT_CTL:
                if ((!msr_info->host_initiated &&
                     !(to_vmx(vcpu)->msr_ia32_feature_control &
                       FEAT_CTL_LMCE_ENABLED)) ||
                    (data & ~MCG_EXT_CTL_LMCE_EN))
                        return 1;
                vcpu->arch.mcg_ext_ctl = data;
                break;
        case MSR_IA32_FEAT_CTL:
                if (!vmx_feature_control_msr_valid(vcpu, data) ||
                    (to_vmx(vcpu)->msr_ia32_feature_control &
                     FEAT_CTL_LOCKED && !msr_info->host_initiated))
                        return 1;
                vmx->msr_ia32_feature_control = data;
                if (msr_info->host_initiated && data == 0)
                        vmx_leave_nested(vcpu);
                break;
        case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
                if (!msr_info->host_initiated)
                        return 1; /* they are read-only */
                if (!nested_vmx_allowed(vcpu))
                        return 1;
                return vmx_set_vmx_msr(vcpu, msr_index, data);
        case MSR_IA32_RTIT_CTL:
                if (!vmx_pt_mode_is_host_guest() ||
                        vmx_rtit_ctl_check(vcpu, data) ||
                        vmx->nested.vmxon)
                        return 1;
                vmcs_write64(GUEST_IA32_RTIT_CTL, data);
                vmx->pt_desc.guest.ctl = data;
                pt_update_intercept_for_msr(vmx);
                break;
        case MSR_IA32_RTIT_STATUS:
                if (!pt_can_write_msr(vmx))
                        return 1;
                if (data & MSR_IA32_RTIT_STATUS_MASK)
                        return 1;
                vmx->pt_desc.guest.status = data;
                break;
        case MSR_IA32_RTIT_CR3_MATCH:
                if (!pt_can_write_msr(vmx))
                        return 1;
                if (!intel_pt_validate_cap(vmx->pt_desc.caps,
                                           PT_CAP_cr3_filtering))
                        return 1;
                vmx->pt_desc.guest.cr3_match = data;
                break;
        case MSR_IA32_RTIT_OUTPUT_BASE:
                if (!pt_can_write_msr(vmx))
                        return 1;
                if (!intel_pt_validate_cap(vmx->pt_desc.caps,
                                           PT_CAP_topa_output) &&
                    !intel_pt_validate_cap(vmx->pt_desc.caps,
                                           PT_CAP_single_range_output))
                        return 1;
                if (!pt_output_base_valid(vcpu, data))
                        return 1;
                vmx->pt_desc.guest.output_base = data;
                break;
        case MSR_IA32_RTIT_OUTPUT_MASK:
                if (!pt_can_write_msr(vmx))
                        return 1;
                if (!intel_pt_validate_cap(vmx->pt_desc.caps,
                                           PT_CAP_topa_output) &&
                    !intel_pt_validate_cap(vmx->pt_desc.caps,
                                           PT_CAP_single_range_output))
                        return 1;
                vmx->pt_desc.guest.output_mask = data;
                break;
        case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
                if (!pt_can_write_msr(vmx))
                        return 1;
                index = msr_info->index - MSR_IA32_RTIT_ADDR0_A;
                if (index >= 2 * intel_pt_validate_cap(vmx->pt_desc.caps,
                                                       PT_CAP_num_address_ranges))
                        return 1;
                if (is_noncanonical_address(data, vcpu))
                        return 1;
                if (index % 2)
                        vmx->pt_desc.guest.addr_b[index / 2] = data;
                else
                        vmx->pt_desc.guest.addr_a[index / 2] = data;
                break;
        case MSR_TSC_AUX:
                if (!msr_info->host_initiated &&
                    !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
                        return 1;
                /* Check reserved bit, higher 32 bits should be zero */
                if ((data >> 32) != 0)
                        return 1;
                goto find_uret_msr;

        default:
        find_uret_msr:
                msr = find_msr_entry(vmx, msr_index);
                if (msr)
                        ret = vmx_set_guest_msr(vmx, msr, data);
                else
                        ret = kvm_set_msr_common(vcpu, msr_info);
        }

        return ret;
}

static void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
{
        unsigned long guest_owned_bits;

        kvm_register_mark_available(vcpu, reg);

        switch (reg) {
        case VCPU_REGS_RSP:
                vcpu->arch.regs[VCPU_REGS_RSP] = vmcs_readl(GUEST_RSP);
                break;
        case VCPU_REGS_RIP:
                vcpu->arch.regs[VCPU_REGS_RIP] = vmcs_readl(GUEST_RIP);
                break;
        case VCPU_EXREG_PDPTR:
                if (enable_ept)
                        ept_save_pdptrs(vcpu);
                break;
        case VCPU_EXREG_CR0:
                guest_owned_bits = vcpu->arch.cr0_guest_owned_bits;

                vcpu->arch.cr0 &= ~guest_owned_bits;
                vcpu->arch.cr0 |= vmcs_readl(GUEST_CR0) & guest_owned_bits;
                break;
        case VCPU_EXREG_CR3:
                if (is_unrestricted_guest(vcpu) ||
                    (enable_ept && is_paging(vcpu)))
                        vcpu->arch.cr3 = vmcs_readl(GUEST_CR3);
                break;
        case VCPU_EXREG_CR4:
                guest_owned_bits = vcpu->arch.cr4_guest_owned_bits;

                vcpu->arch.cr4 &= ~guest_owned_bits;
                vcpu->arch.cr4 |= vmcs_readl(GUEST_CR4) & guest_owned_bits;
                break;
        default:
                WARN_ON_ONCE(1);
                break;
        }
}

static __init int cpu_has_kvm_support(void)
{
        return cpu_has_vmx();
}

static __init int vmx_disabled_by_bios(void)
{
        return !boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
               !boot_cpu_has(X86_FEATURE_VMX);
}

static int kvm_cpu_vmxon(u64 vmxon_pointer)
{
        u64 msr;

        cr4_set_bits(X86_CR4_VMXE);
        intel_pt_handle_vmx(1);

        asm_volatile_goto("1: vmxon %[vmxon_pointer]\n\t"
                          _ASM_EXTABLE(1b, %l[fault])
                          : : [vmxon_pointer] "m"(vmxon_pointer)
                          : : fault);
        return 0;

fault:
        WARN_ONCE(1, "VMXON faulted, MSR_IA32_FEAT_CTL (0x3a) = 0x%llx\n",
                  rdmsrl_safe(MSR_IA32_FEAT_CTL, &msr) ? 0xdeadbeef : msr);
        intel_pt_handle_vmx(0);
        cr4_clear_bits(X86_CR4_VMXE);

        return -EFAULT;
}

static int hardware_enable(void)
{
        int cpu = raw_smp_processor_id();
        u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
        int r;

        if (cr4_read_shadow() & X86_CR4_VMXE)
                return -EBUSY;

        /*
         * This can happen if we hot-added a CPU but failed to allocate
         * VP assist page for it.
         */
        if (static_branch_unlikely(&enable_evmcs) &&
            !hv_get_vp_assist_page(cpu))
                return -EFAULT;

        r = kvm_cpu_vmxon(phys_addr);
        if (r)
                return r;

        if (enable_ept)
                ept_sync_global();

        return 0;
}

static void vmclear_local_loaded_vmcss(void)
{
        int cpu = raw_smp_processor_id();
        struct loaded_vmcs *v, *n;

        list_for_each_entry_safe(v, n, &per_cpu(loaded_vmcss_on_cpu, cpu),
                                 loaded_vmcss_on_cpu_link)
                __loaded_vmcs_clear(v);
}


/* Just like cpu_vmxoff(), but with the __kvm_handle_fault_on_reboot()
 * tricks.
 */
static void kvm_cpu_vmxoff(void)
{
        asm volatile (__ex("vmxoff"));

        intel_pt_handle_vmx(0);
        cr4_clear_bits(X86_CR4_VMXE);
}

static void hardware_disable(void)
{
        vmclear_local_loaded_vmcss();
        kvm_cpu_vmxoff();
}

/*
 * There is no X86_FEATURE for SGX yet, but anyway we need to query CPUID
 * directly instead of going through cpu_has(), to ensure KVM is trapping
 * ENCLS whenever it's supported in hardware.  It does not matter whether
 * the host OS supports or has enabled SGX.
 */
static bool cpu_has_sgx(void)
{
        return cpuid_eax(0) >= 0x12 && (cpuid_eax(0x12) & BIT(0));
}

static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
                                      u32 msr, u32 *result)
{
        u32 vmx_msr_low, vmx_msr_high;
        u32 ctl = ctl_min | ctl_opt;

        rdmsr(msr, vmx_msr_low, vmx_msr_high);

        ctl &= vmx_msr_high; /* bit == 0 in high word ==> must be zero */
        ctl |= vmx_msr_low;  /* bit == 1 in low word  ==> must be one  */

        /* Ensure minimum (required) set of control bits are supported. */
        if (ctl_min & ~ctl)
                return -EIO;

        *result = ctl;
        return 0;
}

static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
                                    struct vmx_capability *vmx_cap)
{
        u32 vmx_msr_low, vmx_msr_high;
        u32 min, opt, min2, opt2;
        u32 _pin_based_exec_control = 0;
        u32 _cpu_based_exec_control = 0;
        u32 _cpu_based_2nd_exec_control = 0;
        u32 _vmexit_control = 0;
        u32 _vmentry_control = 0;

        memset(vmcs_conf, 0, sizeof(*vmcs_conf));
        min = CPU_BASED_HLT_EXITING |
#ifdef CONFIG_X86_64
              CPU_BASED_CR8_LOAD_EXITING |
              CPU_BASED_CR8_STORE_EXITING |
#endif
              CPU_BASED_CR3_LOAD_EXITING |
              CPU_BASED_CR3_STORE_EXITING |
              CPU_BASED_UNCOND_IO_EXITING |
              CPU_BASED_MOV_DR_EXITING |
              CPU_BASED_USE_TSC_OFFSETTING |
              CPU_BASED_MWAIT_EXITING |
              CPU_BASED_MONITOR_EXITING |
              CPU_BASED_INVLPG_EXITING |
              CPU_BASED_RDPMC_EXITING;

        opt = CPU_BASED_TPR_SHADOW |
              CPU_BASED_USE_MSR_BITMAPS |
              CPU_BASED_ACTIVATE_SECONDARY_CONTROLS;
        if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_PROCBASED_CTLS,
                                &_cpu_based_exec_control) < 0)
                return -EIO;
#ifdef CONFIG_X86_64
        if ((_cpu_based_exec_control & CPU_BASED_TPR_SHADOW))
                _cpu_based_exec_control &= ~CPU_BASED_CR8_LOAD_EXITING &
                                           ~CPU_BASED_CR8_STORE_EXITING;
#endif
        if (_cpu_based_exec_control & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS) {
                min2 = 0;
                opt2 = SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
                        SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
                        SECONDARY_EXEC_WBINVD_EXITING |
                        SECONDARY_EXEC_ENABLE_VPID |
                        SECONDARY_EXEC_ENABLE_EPT |
                        SECONDARY_EXEC_UNRESTRICTED_GUEST |
                        SECONDARY_EXEC_PAUSE_LOOP_EXITING |
                        SECONDARY_EXEC_DESC |
                        SECONDARY_EXEC_ENABLE_RDTSCP |
                        SECONDARY_EXEC_ENABLE_INVPCID |
                        SECONDARY_EXEC_APIC_REGISTER_VIRT |
                        SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
                        SECONDARY_EXEC_SHADOW_VMCS |
                        SECONDARY_EXEC_XSAVES |
                        SECONDARY_EXEC_RDSEED_EXITING |
                        SECONDARY_EXEC_RDRAND_EXITING |
                        SECONDARY_EXEC_ENABLE_PML |
                        SECONDARY_EXEC_TSC_SCALING |
                        SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE |
                        SECONDARY_EXEC_PT_USE_GPA |
                        SECONDARY_EXEC_PT_CONCEAL_VMX |
                        SECONDARY_EXEC_ENABLE_VMFUNC;
                if (cpu_has_sgx())
                        opt2 |= SECONDARY_EXEC_ENCLS_EXITING;
                if (adjust_vmx_controls(min2, opt2,
                                        MSR_IA32_VMX_PROCBASED_CTLS2,
                                        &_cpu_based_2nd_exec_control) < 0)
                        return -EIO;
        }
#ifndef CONFIG_X86_64
        if (!(_cpu_based_2nd_exec_control &
                                SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES))
                _cpu_based_exec_control &= ~CPU_BASED_TPR_SHADOW;
#endif

        if (!(_cpu_based_exec_control & CPU_BASED_TPR_SHADOW))
                _cpu_based_2nd_exec_control &= ~(
                                SECONDARY_EXEC_APIC_REGISTER_VIRT |
                                SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
                                SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);

        rdmsr_safe(MSR_IA32_VMX_EPT_VPID_CAP,
                &vmx_cap->ept, &vmx_cap->vpid);

        if (_cpu_based_2nd_exec_control & SECONDARY_EXEC_ENABLE_EPT) {
                /* CR3 accesses and invlpg don't need to cause VM Exits when EPT
                   enabled */
                _cpu_based_exec_control &= ~(CPU_BASED_CR3_LOAD_EXITING |
                                             CPU_BASED_CR3_STORE_EXITING |
                                             CPU_BASED_INVLPG_EXITING);
        } else if (vmx_cap->ept) {
                vmx_cap->ept = 0;
                pr_warn_once("EPT CAP should not exist if not support "
                                "1-setting enable EPT VM-execution control\n");
        }
        if (!(_cpu_based_2nd_exec_control & SECONDARY_EXEC_ENABLE_VPID) &&
                vmx_cap->vpid) {
                vmx_cap->vpid = 0;
                pr_warn_once("VPID CAP should not exist if not support "
                                "1-setting enable VPID VM-execution control\n");
        }

        min = VM_EXIT_SAVE_DEBUG_CONTROLS | VM_EXIT_ACK_INTR_ON_EXIT;
#ifdef CONFIG_X86_64
        min |= VM_EXIT_HOST_ADDR_SPACE_SIZE;
#endif
        opt = VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL |
              VM_EXIT_LOAD_IA32_PAT |
              VM_EXIT_LOAD_IA32_EFER |
              VM_EXIT_CLEAR_BNDCFGS |
              VM_EXIT_PT_CONCEAL_PIP |
              VM_EXIT_CLEAR_IA32_RTIT_CTL;
        if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_EXIT_CTLS,
                                &_vmexit_control) < 0)
                return -EIO;

        min = PIN_BASED_EXT_INTR_MASK | PIN_BASED_NMI_EXITING;
        opt = PIN_BASED_VIRTUAL_NMIS | PIN_BASED_POSTED_INTR |
                 PIN_BASED_VMX_PREEMPTION_TIMER;
        if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_PINBASED_CTLS,
                                &_pin_based_exec_control) < 0)
                return -EIO;

        if (cpu_has_broken_vmx_preemption_timer())
                _pin_based_exec_control &= ~PIN_BASED_VMX_PREEMPTION_TIMER;
        if (!(_cpu_based_2nd_exec_control &
                SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY))
                _pin_based_exec_control &= ~PIN_BASED_POSTED_INTR;

        min = VM_ENTRY_LOAD_DEBUG_CONTROLS;
        opt = VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL |
              VM_ENTRY_LOAD_IA32_PAT |
              VM_ENTRY_LOAD_IA32_EFER |
              VM_ENTRY_LOAD_BNDCFGS |
              VM_ENTRY_PT_CONCEAL_PIP |
              VM_ENTRY_LOAD_IA32_RTIT_CTL;
        if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_ENTRY_CTLS,
                                &_vmentry_control) < 0)
                return -EIO;

        /*
         * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they
         * can't be used due to an errata where VM Exit may incorrectly clear
         * IA32_PERF_GLOBAL_CTRL[34:32].  Workaround the errata by using the
         * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL.
         */
        if (boot_cpu_data.x86 == 0x6) {
                switch (boot_cpu_data.x86_model) {
                case 26: /* AAK155 */
                case 30: /* AAP115 */
                case 37: /* AAT100 */
                case 44: /* BC86,AAY89,BD102 */
                case 46: /* BA97 */
                        _vmentry_control &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL;
                        _vmexit_control &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL;
                        pr_warn_once("kvm: VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL "
                                        "does not work properly. Using workaround\n");
                        break;
                default:
                        break;
                }
        }


        rdmsr(MSR_IA32_VMX_BASIC, vmx_msr_low, vmx_msr_high);

        /* IA-32 SDM Vol 3B: VMCS size is never greater than 4kB. */
        if ((vmx_msr_high & 0x1fff) > PAGE_SIZE)
                return -EIO;

#ifdef CONFIG_X86_64
        /* IA-32 SDM Vol 3B: 64-bit CPUs always have VMX_BASIC_MSR[48]==0. */
        if (vmx_msr_high & (1u<<16))
                return -EIO;
#endif

        /* Require Write-Back (WB) memory type for VMCS accesses. */
        if (((vmx_msr_high >> 18) & 15) != 6)
                return -EIO;

        vmcs_conf->size = vmx_msr_high & 0x1fff;
        vmcs_conf->order = get_order(vmcs_conf->size);
        vmcs_conf->basic_cap = vmx_msr_high & ~0x1fff;

        vmcs_conf->revision_id = vmx_msr_low;

        vmcs_conf->pin_based_exec_ctrl = _pin_based_exec_control;
        vmcs_conf->cpu_based_exec_ctrl = _cpu_based_exec_control;
        vmcs_conf->cpu_based_2nd_exec_ctrl = _cpu_based_2nd_exec_control;
        vmcs_conf->vmexit_ctrl         = _vmexit_control;
        vmcs_conf->vmentry_ctrl        = _vmentry_control;

        if (static_branch_unlikely(&enable_evmcs))
                evmcs_sanitize_exec_ctrls(vmcs_conf);

        return 0;
}

struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags)
{
        int node = cpu_to_node(cpu);
        struct page *pages;
        struct vmcs *vmcs;

        pages = __alloc_pages_node(node, flags, vmcs_config.order);
        if (!pages)
                return NULL;
        vmcs = page_address(pages);
        memset(vmcs, 0, vmcs_config.size);

        /* KVM supports Enlightened VMCS v1 only */
        if (static_branch_unlikely(&enable_evmcs))
                vmcs->hdr.revision_id = KVM_EVMCS_VERSION;
        else
                vmcs->hdr.revision_id = vmcs_config.revision_id;

        if (shadow)
                vmcs->hdr.shadow_vmcs = 1;
        return vmcs;
}

void free_vmcs(struct vmcs *vmcs)
{
        free_pages((unsigned long)vmcs, vmcs_config.order);
}

/*
 * Free a VMCS, but before that VMCLEAR it on the CPU where it was last loaded
 */
void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
{
        if (!loaded_vmcs->vmcs)
                return;
        loaded_vmcs_clear(loaded_vmcs);
        free_vmcs(loaded_vmcs->vmcs);
        loaded_vmcs->vmcs = NULL;
        if (loaded_vmcs->msr_bitmap)
                free_page((unsigned long)loaded_vmcs->msr_bitmap);
        WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
}

int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
{
        loaded_vmcs->vmcs = alloc_vmcs(false);
        if (!loaded_vmcs->vmcs)
                return -ENOMEM;

        vmcs_clear(loaded_vmcs->vmcs);

        loaded_vmcs->shadow_vmcs = NULL;
        loaded_vmcs->hv_timer_soft_disabled = false;
        loaded_vmcs->cpu = -1;
        loaded_vmcs->launched = 0;

        if (cpu_has_vmx_msr_bitmap()) {
                loaded_vmcs->msr_bitmap = (unsigned long *)
                                __get_free_page(GFP_KERNEL_ACCOUNT);
                if (!loaded_vmcs->msr_bitmap)
                        goto out_vmcs;
                memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE);

                if (IS_ENABLED(CONFIG_HYPERV) &&
                    static_branch_unlikely(&enable_evmcs) &&
                    (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)) {
                        struct hv_enlightened_vmcs *evmcs =
                                (struct hv_enlightened_vmcs *)loaded_vmcs->vmcs;

                        evmcs->hv_enlightenments_control.msr_bitmap = 1;
                }
        }

        memset(&loaded_vmcs->host_state, 0, sizeof(struct vmcs_host_state));
        memset(&loaded_vmcs->controls_shadow, 0,
                sizeof(struct vmcs_controls_shadow));

        return 0;

out_vmcs:
        free_loaded_vmcs(loaded_vmcs);
        return -ENOMEM;
}

static void free_kvm_area(void)
{
        int cpu;

        for_each_possible_cpu(cpu) {
                free_vmcs(per_cpu(vmxarea, cpu));
                per_cpu(vmxarea, cpu) = NULL;
        }
}

static __init int alloc_kvm_area(void)
{
        int cpu;

        for_each_possible_cpu(cpu) {
                struct vmcs *vmcs;

                vmcs = alloc_vmcs_cpu(false, cpu, GFP_KERNEL);
                if (!vmcs) {
                        free_kvm_area();
                        return -ENOMEM;
                }

                /*
                 * When eVMCS is enabled, alloc_vmcs_cpu() sets
                 * vmcs->revision_id to KVM_EVMCS_VERSION instead of
                 * revision_id reported by MSR_IA32_VMX_BASIC.
                 *
                 * However, even though not explicitly documented by
                 * TLFS, VMXArea passed as VMXON argument should
                 * still be marked with revision_id reported by
                 * physical CPU.
                 */
                if (static_branch_unlikely(&enable_evmcs))
                        vmcs->hdr.revision_id = vmcs_config.revision_id;

                per_cpu(vmxarea, cpu) = vmcs;
        }
        return 0;
}

static void fix_pmode_seg(struct kvm_vcpu *vcpu, int seg,
                struct kvm_segment *save)
{
        if (!emulate_invalid_guest_state) {
                /*
                 * CS and SS RPL should be equal during guest entry according
                 * to VMX spec, but in reality it is not always so. Since vcpu
                 * is in the middle of the transition from real mode to
                 * protected mode it is safe to assume that RPL 0 is a good
                 * default value.
                 */
                if (seg == VCPU_SREG_CS || seg == VCPU_SREG_SS)
                        save->selector &= ~SEGMENT_RPL_MASK;
                save->dpl = save->selector & SEGMENT_RPL_MASK;
                save->s = 1;
        }
        vmx_set_segment(vcpu, save, seg);
}

static void enter_pmode(struct kvm_vcpu *vcpu)
{
        unsigned long flags;
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        /*
         * Update real mode segment cache. It may be not up-to-date if sement
         * register was written while vcpu was in a guest mode.
         */
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_ES], VCPU_SREG_ES);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_DS], VCPU_SREG_DS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_FS], VCPU_SREG_FS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_GS], VCPU_SREG_GS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_SS], VCPU_SREG_SS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_CS], VCPU_SREG_CS);

        vmx->rmode.vm86_active = 0;

        vmx_set_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR);

        flags = vmcs_readl(GUEST_RFLAGS);
        flags &= RMODE_GUEST_OWNED_EFLAGS_BITS;
        flags |= vmx->rmode.save_rflags & ~RMODE_GUEST_OWNED_EFLAGS_BITS;
        vmcs_writel(GUEST_RFLAGS, flags);

        vmcs_writel(GUEST_CR4, (vmcs_readl(GUEST_CR4) & ~X86_CR4_VME) |
                        (vmcs_readl(CR4_READ_SHADOW) & X86_CR4_VME));

        update_exception_bitmap(vcpu);

        fix_pmode_seg(vcpu, VCPU_SREG_CS, &vmx->rmode.segs[VCPU_SREG_CS]);
        fix_pmode_seg(vcpu, VCPU_SREG_SS, &vmx->rmode.segs[VCPU_SREG_SS]);
        fix_pmode_seg(vcpu, VCPU_SREG_ES, &vmx->rmode.segs[VCPU_SREG_ES]);
        fix_pmode_seg(vcpu, VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]);
        fix_pmode_seg(vcpu, VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]);
        fix_pmode_seg(vcpu, VCPU_SREG_GS, &vmx->rmode.segs[VCPU_SREG_GS]);
}

static void fix_rmode_seg(int seg, struct kvm_segment *save)
{
        const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
        struct kvm_segment var = *save;

        var.dpl = 0x3;
        if (seg == VCPU_SREG_CS)
                var.type = 0x3;

        if (!emulate_invalid_guest_state) {
                var.selector = var.base >> 4;
                var.base = var.base & 0xffff0;
                var.limit = 0xffff;
                var.g = 0;
                var.db = 0;
                var.present = 1;
                var.s = 1;
                var.l = 0;
                var.unusable = 0;
                var.type = 0x3;
                var.avl = 0;
                if (save->base & 0xf)
                        printk_once(KERN_WARNING "kvm: segment base is not "
                                        "paragraph aligned when entering "
                                        "protected mode (seg=%d)", seg);
        }

        vmcs_write16(sf->selector, var.selector);
        vmcs_writel(sf->base, var.base);
        vmcs_write32(sf->limit, var.limit);
        vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(&var));
}

static void enter_rmode(struct kvm_vcpu *vcpu)
{
        unsigned long flags;
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct kvm_vmx *kvm_vmx = to_kvm_vmx(vcpu->kvm);

        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_ES], VCPU_SREG_ES);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_DS], VCPU_SREG_DS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_FS], VCPU_SREG_FS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_GS], VCPU_SREG_GS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_SS], VCPU_SREG_SS);
        vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_CS], VCPU_SREG_CS);

        vmx->rmode.vm86_active = 1;

        /*
         * Very old userspace does not call KVM_SET_TSS_ADDR before entering
         * vcpu. Warn the user that an update is overdue.
         */
        if (!kvm_vmx->tss_addr)
                printk_once(KERN_WARNING "kvm: KVM_SET_TSS_ADDR need to be "
                             "called before entering vcpu\n");

        vmx_segment_cache_clear(vmx);

        vmcs_writel(GUEST_TR_BASE, kvm_vmx->tss_addr);
        vmcs_write32(GUEST_TR_LIMIT, RMODE_TSS_SIZE - 1);
        vmcs_write32(GUEST_TR_AR_BYTES, 0x008b);

        flags = vmcs_readl(GUEST_RFLAGS);
        vmx->rmode.save_rflags = flags;

        flags |= X86_EFLAGS_IOPL | X86_EFLAGS_VM;

        vmcs_writel(GUEST_RFLAGS, flags);
        vmcs_writel(GUEST_CR4, vmcs_readl(GUEST_CR4) | X86_CR4_VME);
        update_exception_bitmap(vcpu);

        fix_rmode_seg(VCPU_SREG_SS, &vmx->rmode.segs[VCPU_SREG_SS]);
        fix_rmode_seg(VCPU_SREG_CS, &vmx->rmode.segs[VCPU_SREG_CS]);
        fix_rmode_seg(VCPU_SREG_ES, &vmx->rmode.segs[VCPU_SREG_ES]);
        fix_rmode_seg(VCPU_SREG_DS, &vmx->rmode.segs[VCPU_SREG_DS]);
        fix_rmode_seg(VCPU_SREG_GS, &vmx->rmode.segs[VCPU_SREG_GS]);
        fix_rmode_seg(VCPU_SREG_FS, &vmx->rmode.segs[VCPU_SREG_FS]);

        kvm_mmu_reset_context(vcpu);
}

void vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct vmx_uret_msr *msr = find_msr_entry(vmx, MSR_EFER);

        if (!msr)
                return;

        vcpu->arch.efer = efer;
        if (efer & EFER_LMA) {
                vm_entry_controls_setbit(to_vmx(vcpu), VM_ENTRY_IA32E_MODE);
                msr->data = efer;
        } else {
                vm_entry_controls_clearbit(to_vmx(vcpu), VM_ENTRY_IA32E_MODE);

                msr->data = efer & ~EFER_LME;
        }
        setup_msrs(vmx);
}

#ifdef CONFIG_X86_64

static void enter_lmode(struct kvm_vcpu *vcpu)
{
        u32 guest_tr_ar;

        vmx_segment_cache_clear(to_vmx(vcpu));

        guest_tr_ar = vmcs_read32(GUEST_TR_AR_BYTES);
        if ((guest_tr_ar & VMX_AR_TYPE_MASK) != VMX_AR_TYPE_BUSY_64_TSS) {
                pr_debug_ratelimited("%s: tss fixup for long mode. \n",
                                     __func__);
                vmcs_write32(GUEST_TR_AR_BYTES,
                             (guest_tr_ar & ~VMX_AR_TYPE_MASK)
                             | VMX_AR_TYPE_BUSY_64_TSS);
        }
        vmx_set_efer(vcpu, vcpu->arch.efer | EFER_LMA);
}

static void exit_lmode(struct kvm_vcpu *vcpu)
{
        vm_entry_controls_clearbit(to_vmx(vcpu), VM_ENTRY_IA32E_MODE);
        vmx_set_efer(vcpu, vcpu->arch.efer & ~EFER_LMA);
}

#endif

static void vmx_flush_tlb_all(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        /*
         * INVEPT must be issued when EPT is enabled, irrespective of VPID, as
         * the CPU is not required to invalidate guest-physical mappings on
         * VM-Entry, even if VPID is disabled.  Guest-physical mappings are
         * associated with the root EPT structure and not any particular VPID
         * (INVVPID also isn't required to invalidate guest-physical mappings).
         */
        if (enable_ept) {
                ept_sync_global();
        } else if (enable_vpid) {
                if (cpu_has_vmx_invvpid_global()) {
                        vpid_sync_vcpu_global();
                } else {
                        vpid_sync_vcpu_single(vmx->vpid);
                        vpid_sync_vcpu_single(vmx->nested.vpid02);
                }
        }
}

static void vmx_flush_tlb_current(struct kvm_vcpu *vcpu)
{
        struct kvm_mmu *mmu = vcpu->arch.mmu;
        u64 root_hpa = mmu->root_hpa;

        /* No flush required if the current context is invalid. */
        if (!VALID_PAGE(root_hpa))
                return;

        if (enable_ept)
                ept_sync_context(construct_eptp(vcpu, root_hpa,
                                                mmu->shadow_root_level));
        else if (!is_guest_mode(vcpu))
                vpid_sync_context(to_vmx(vcpu)->vpid);
        else
                vpid_sync_context(nested_get_vpid02(vcpu));
}

static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
{
        /*
         * vpid_sync_vcpu_addr() is a nop if vmx->vpid==0, see the comment in
         * vmx_flush_tlb_guest() for an explanation of why this is ok.
         */
        vpid_sync_vcpu_addr(to_vmx(vcpu)->vpid, addr);
}

static void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu)
{
        /*
         * vpid_sync_context() is a nop if vmx->vpid==0, e.g. if enable_vpid==0
         * or a vpid couldn't be allocated for this vCPU.  VM-Enter and VM-Exit
         * are required to flush GVA->{G,H}PA mappings from the TLB if vpid is
         * disabled (VM-Enter with vpid enabled and vpid==0 is disallowed),
         * i.e. no explicit INVVPID is necessary.
         */
        vpid_sync_context(to_vmx(vcpu)->vpid);
}

void vmx_ept_load_pdptrs(struct kvm_vcpu *vcpu)
{
        struct kvm_mmu *mmu = vcpu->arch.walk_mmu;

        if (!kvm_register_is_dirty(vcpu, VCPU_EXREG_PDPTR))
                return;

        if (is_pae_paging(vcpu)) {
                vmcs_write64(GUEST_PDPTR0, mmu->pdptrs[0]);
                vmcs_write64(GUEST_PDPTR1, mmu->pdptrs[1]);
                vmcs_write64(GUEST_PDPTR2, mmu->pdptrs[2]);
                vmcs_write64(GUEST_PDPTR3, mmu->pdptrs[3]);
        }
}

void ept_save_pdptrs(struct kvm_vcpu *vcpu)
{
        struct kvm_mmu *mmu = vcpu->arch.walk_mmu;

        if (WARN_ON_ONCE(!is_pae_paging(vcpu)))
                return;

        mmu->pdptrs[0] = vmcs_read64(GUEST_PDPTR0);
        mmu->pdptrs[1] = vmcs_read64(GUEST_PDPTR1);
        mmu->pdptrs[2] = vmcs_read64(GUEST_PDPTR2);
        mmu->pdptrs[3] = vmcs_read64(GUEST_PDPTR3);

        kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR);
}

static void ept_update_paging_mode_cr0(unsigned long *hw_cr0,
                                        unsigned long cr0,
                                        struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (!kvm_register_is_available(vcpu, VCPU_EXREG_CR3))
                vmx_cache_reg(vcpu, VCPU_EXREG_CR3);
        if (!(cr0 & X86_CR0_PG)) {
                /* From paging/starting to nonpaging */
                exec_controls_setbit(vmx, CPU_BASED_CR3_LOAD_EXITING |
                                          CPU_BASED_CR3_STORE_EXITING);
                vcpu->arch.cr0 = cr0;
                vmx_set_cr4(vcpu, kvm_read_cr4(vcpu));
        } else if (!is_paging(vcpu)) {
                /* From nonpaging to paging */
                exec_controls_clearbit(vmx, CPU_BASED_CR3_LOAD_EXITING |
                                            CPU_BASED_CR3_STORE_EXITING);
                vcpu->arch.cr0 = cr0;
                vmx_set_cr4(vcpu, kvm_read_cr4(vcpu));
        }

        if (!(cr0 & X86_CR0_WP))
                *hw_cr0 &= ~X86_CR0_WP;
}

void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long hw_cr0;

        hw_cr0 = (cr0 & ~KVM_VM_CR0_ALWAYS_OFF);
        if (is_unrestricted_guest(vcpu))
                hw_cr0 |= KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST;
        else {
                hw_cr0 |= KVM_VM_CR0_ALWAYS_ON;

                if (vmx->rmode.vm86_active && (cr0 & X86_CR0_PE))
                        enter_pmode(vcpu);

                if (!vmx->rmode.vm86_active && !(cr0 & X86_CR0_PE))
                        enter_rmode(vcpu);
        }

#ifdef CONFIG_X86_64
        if (vcpu->arch.efer & EFER_LME) {
                if (!is_paging(vcpu) && (cr0 & X86_CR0_PG))
                        enter_lmode(vcpu);
                if (is_paging(vcpu) && !(cr0 & X86_CR0_PG))
                        exit_lmode(vcpu);
        }
#endif

        if (enable_ept && !is_unrestricted_guest(vcpu))
                ept_update_paging_mode_cr0(&hw_cr0, cr0, vcpu);

        vmcs_writel(CR0_READ_SHADOW, cr0);
        vmcs_writel(GUEST_CR0, hw_cr0);
        vcpu->arch.cr0 = cr0;
        kvm_register_mark_available(vcpu, VCPU_EXREG_CR0);

        /* depends on vcpu->arch.cr0 to be set to a new value */
        vmx->emulation_required = emulation_required(vcpu);
}

static int vmx_get_max_tdp_level(void)
{
        if (cpu_has_vmx_ept_5levels())
                return 5;
        return 4;
}

u64 construct_eptp(struct kvm_vcpu *vcpu, unsigned long root_hpa,
                   int root_level)
{
        u64 eptp = VMX_EPTP_MT_WB;

        eptp |= (root_level == 5) ? VMX_EPTP_PWL_5 : VMX_EPTP_PWL_4;

        if (enable_ept_ad_bits &&
            (!is_guest_mode(vcpu) || nested_ept_ad_enabled(vcpu)))
                eptp |= VMX_EPTP_AD_ENABLE_BIT;
        eptp |= (root_hpa & PAGE_MASK);

        return eptp;
}

static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long pgd,
                             int pgd_level)
{
        struct kvm *kvm = vcpu->kvm;
        bool update_guest_cr3 = true;
        unsigned long guest_cr3;
        u64 eptp;

        if (enable_ept) {
                eptp = construct_eptp(vcpu, pgd, pgd_level);
                vmcs_write64(EPT_POINTER, eptp);

                if (kvm_x86_ops.tlb_remote_flush) {
                        spin_lock(&to_kvm_vmx(kvm)->ept_pointer_lock);
                        to_vmx(vcpu)->ept_pointer = eptp;
                        to_kvm_vmx(kvm)->ept_pointers_match
                                = EPT_POINTERS_CHECK;
                        spin_unlock(&to_kvm_vmx(kvm)->ept_pointer_lock);
                }

                if (!enable_unrestricted_guest && !is_paging(vcpu))
                        guest_cr3 = to_kvm_vmx(kvm)->ept_identity_map_addr;
                else if (test_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail))
                        guest_cr3 = vcpu->arch.cr3;
                else /* vmcs01.GUEST_CR3 is already up-to-date. */
                        update_guest_cr3 = false;
                vmx_ept_load_pdptrs(vcpu);
        } else {
                guest_cr3 = pgd;
        }

        if (update_guest_cr3)
                vmcs_writel(GUEST_CR3, guest_cr3);
}

int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        /*
         * Pass through host's Machine Check Enable value to hw_cr4, which
         * is in force while we are in guest mode.  Do not let guests control
         * this bit, even if host CR4.MCE == 0.
         */
        unsigned long hw_cr4;

        hw_cr4 = (cr4_read_shadow() & X86_CR4_MCE) | (cr4 & ~X86_CR4_MCE);
        if (is_unrestricted_guest(vcpu))
                hw_cr4 |= KVM_VM_CR4_ALWAYS_ON_UNRESTRICTED_GUEST;
        else if (vmx->rmode.vm86_active)
                hw_cr4 |= KVM_RMODE_VM_CR4_ALWAYS_ON;
        else
                hw_cr4 |= KVM_PMODE_VM_CR4_ALWAYS_ON;

        if (!boot_cpu_has(X86_FEATURE_UMIP) && vmx_umip_emulated()) {
                if (cr4 & X86_CR4_UMIP) {
                        secondary_exec_controls_setbit(vmx, SECONDARY_EXEC_DESC);
                        hw_cr4 &= ~X86_CR4_UMIP;
                } else if (!is_guest_mode(vcpu) ||
                        !nested_cpu_has2(get_vmcs12(vcpu), SECONDARY_EXEC_DESC)) {
                        secondary_exec_controls_clearbit(vmx, SECONDARY_EXEC_DESC);
                }
        }

        if (cr4 & X86_CR4_VMXE) {
                /*
                 * To use VMXON (and later other VMX instructions), a guest
                 * must first be able to turn on cr4.VMXE (see handle_vmon()).
                 * So basically the check on whether to allow nested VMX
                 * is here.  We operate under the default treatment of SMM,
                 * so VMX cannot be enabled under SMM.
                 */
                if (!nested_vmx_allowed(vcpu) || is_smm(vcpu))
                        return 1;
        }

        if (vmx->nested.vmxon && !nested_cr4_valid(vcpu, cr4))
                return 1;

        vcpu->arch.cr4 = cr4;
        kvm_register_mark_available(vcpu, VCPU_EXREG_CR4);

        if (!is_unrestricted_guest(vcpu)) {
                if (enable_ept) {
                        if (!is_paging(vcpu)) {
                                hw_cr4 &= ~X86_CR4_PAE;
                                hw_cr4 |= X86_CR4_PSE;
                        } else if (!(cr4 & X86_CR4_PAE)) {
                                hw_cr4 &= ~X86_CR4_PAE;
                        }
                }

                /*
                 * SMEP/SMAP/PKU is disabled if CPU is in non-paging mode in
                 * hardware.  To emulate this behavior, SMEP/SMAP/PKU needs
                 * to be manually disabled when guest switches to non-paging
                 * mode.
                 *
                 * If !enable_unrestricted_guest, the CPU is always running
                 * with CR0.PG=1 and CR4 needs to be modified.
                 * If enable_unrestricted_guest, the CPU automatically
                 * disables SMEP/SMAP/PKU when the guest sets CR0.PG=0.
                 */
                if (!is_paging(vcpu))
                        hw_cr4 &= ~(X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE);
        }

        vmcs_writel(CR4_READ_SHADOW, cr4);
        vmcs_writel(GUEST_CR4, hw_cr4);
        return 0;
}

void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        u32 ar;

        if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) {
                *var = vmx->rmode.segs[seg];
                if (seg == VCPU_SREG_TR
                    || var->selector == vmx_read_guest_seg_selector(vmx, seg))
                        return;
                var->base = vmx_read_guest_seg_base(vmx, seg);
                var->selector = vmx_read_guest_seg_selector(vmx, seg);
                return;
        }
        var->base = vmx_read_guest_seg_base(vmx, seg);
        var->limit = vmx_read_guest_seg_limit(vmx, seg);
        var->selector = vmx_read_guest_seg_selector(vmx, seg);
        ar = vmx_read_guest_seg_ar(vmx, seg);
        var->unusable = (ar >> 16) & 1;
        var->type = ar & 15;
        var->s = (ar >> 4) & 1;
        var->dpl = (ar >> 5) & 3;
        /*
         * Some userspaces do not preserve unusable property. Since usable
         * segment has to be present according to VMX spec we can use present
         * property to amend userspace bug by making unusable segment always
         * nonpresent. vmx_segment_access_rights() already marks nonpresent
         * segment as unusable.
         */
        var->present = !var->unusable;
        var->avl = (ar >> 12) & 1;
        var->l = (ar >> 13) & 1;
        var->db = (ar >> 14) & 1;
        var->g = (ar >> 15) & 1;
}

static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
{
        struct kvm_segment s;

        if (to_vmx(vcpu)->rmode.vm86_active) {
                vmx_get_segment(vcpu, &s, seg);
                return s.base;
        }
        return vmx_read_guest_seg_base(to_vmx(vcpu), seg);
}

int vmx_get_cpl(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (unlikely(vmx->rmode.vm86_active))
                return 0;
        else {
                int ar = vmx_read_guest_seg_ar(vmx, VCPU_SREG_SS);
                return VMX_AR_DPL(ar);
        }
}

static u32 vmx_segment_access_rights(struct kvm_segment *var)
{
        u32 ar;

        if (var->unusable || !var->present)
                ar = 1 << 16;
        else {
                ar = var->type & 15;
                ar |= (var->s & 1) << 4;
                ar |= (var->dpl & 3) << 5;
                ar |= (var->present & 1) << 7;
                ar |= (var->avl & 1) << 12;
                ar |= (var->l & 1) << 13;
                ar |= (var->db & 1) << 14;
                ar |= (var->g & 1) << 15;
        }

        return ar;
}

void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];

        vmx_segment_cache_clear(vmx);

        if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) {
                vmx->rmode.segs[seg] = *var;
                if (seg == VCPU_SREG_TR)
                        vmcs_write16(sf->selector, var->selector);
                else if (var->s)
                        fix_rmode_seg(seg, &vmx->rmode.segs[seg]);
                goto out;
        }

        vmcs_writel(sf->base, var->base);
        vmcs_write32(sf->limit, var->limit);
        vmcs_write16(sf->selector, var->selector);

        /*
         *   Fix the "Accessed" bit in AR field of segment registers for older
         * qemu binaries.
         *   IA32 arch specifies that at the time of processor reset the
         * "Accessed" bit in the AR field of segment registers is 1. And qemu
         * is setting it to 0 in the userland code. This causes invalid guest
         * state vmexit when "unrestricted guest" mode is turned on.
         *    Fix for this setup issue in cpu_reset is being pushed in the qemu
         * tree. Newer qemu binaries with that qemu fix would not need this
         * kvm hack.
         */
        if (is_unrestricted_guest(vcpu) && (seg != VCPU_SREG_LDTR))
                var->type |= 0x1; /* Accessed */

        vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(var));

out:
        vmx->emulation_required = emulation_required(vcpu);
}

static void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
{
        u32 ar = vmx_read_guest_seg_ar(to_vmx(vcpu), VCPU_SREG_CS);

        *db = (ar >> 14) & 1;
        *l = (ar >> 13) & 1;
}

static void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
        dt->size = vmcs_read32(GUEST_IDTR_LIMIT);
        dt->address = vmcs_readl(GUEST_IDTR_BASE);
}

static void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
        vmcs_write32(GUEST_IDTR_LIMIT, dt->size);
        vmcs_writel(GUEST_IDTR_BASE, dt->address);
}

static void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
        dt->size = vmcs_read32(GUEST_GDTR_LIMIT);
        dt->address = vmcs_readl(GUEST_GDTR_BASE);
}

static void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
        vmcs_write32(GUEST_GDTR_LIMIT, dt->size);
        vmcs_writel(GUEST_GDTR_BASE, dt->address);
}

static bool rmode_segment_valid(struct kvm_vcpu *vcpu, int seg)
{
        struct kvm_segment var;
        u32 ar;

        vmx_get_segment(vcpu, &var, seg);
        var.dpl = 0x3;
        if (seg == VCPU_SREG_CS)
                var.type = 0x3;
        ar = vmx_segment_access_rights(&var);

        if (var.base != (var.selector << 4))
                return false;
        if (var.limit != 0xffff)
                return false;
        if (ar != 0xf3)
                return false;

        return true;
}

static bool code_segment_valid(struct kvm_vcpu *vcpu)
{
        struct kvm_segment cs;
        unsigned int cs_rpl;

        vmx_get_segment(vcpu, &cs, VCPU_SREG_CS);
        cs_rpl = cs.selector & SEGMENT_RPL_MASK;

        if (cs.unusable)
                return false;
        if (~cs.type & (VMX_AR_TYPE_CODE_MASK|VMX_AR_TYPE_ACCESSES_MASK))
                return false;
        if (!cs.s)
                return false;
        if (cs.type & VMX_AR_TYPE_WRITEABLE_MASK) {
                if (cs.dpl > cs_rpl)
                        return false;
        } else {
                if (cs.dpl != cs_rpl)
                        return false;
        }
        if (!cs.present)
                return false;

        /* TODO: Add Reserved field check, this'll require a new member in the kvm_segment_field structure */
        return true;
}

static bool stack_segment_valid(struct kvm_vcpu *vcpu)
{
        struct kvm_segment ss;
        unsigned int ss_rpl;

        vmx_get_segment(vcpu, &ss, VCPU_SREG_SS);
        ss_rpl = ss.selector & SEGMENT_RPL_MASK;

        if (ss.unusable)
                return true;
        if (ss.type != 3 && ss.type != 7)
                return false;
        if (!ss.s)
                return false;
        if (ss.dpl != ss_rpl) /* DPL != RPL */
                return false;
        if (!ss.present)
                return false;

        return true;
}

static bool data_segment_valid(struct kvm_vcpu *vcpu, int seg)
{
        struct kvm_segment var;
        unsigned int rpl;

        vmx_get_segment(vcpu, &var, seg);
        rpl = var.selector & SEGMENT_RPL_MASK;

        if (var.unusable)
                return true;
        if (!var.s)
                return false;
        if (!var.present)
                return false;
        if (~var.type & (VMX_AR_TYPE_CODE_MASK|VMX_AR_TYPE_WRITEABLE_MASK)) {
                if (var.dpl < rpl) /* DPL < RPL */
                        return false;
        }

        /* TODO: Add other members to kvm_segment_field to allow checking for other access
         * rights flags
         */
        return true;
}

static bool tr_valid(struct kvm_vcpu *vcpu)
{
        struct kvm_segment tr;

        vmx_get_segment(vcpu, &tr, VCPU_SREG_TR);

        if (tr.unusable)
                return false;
        if (tr.selector & SEGMENT_TI_MASK)      /* TI = 1 */
                return false;
        if (tr.type != 3 && tr.type != 11) /* TODO: Check if guest is in IA32e mode */
                return false;
        if (!tr.present)
                return false;

        return true;
}

static bool ldtr_valid(struct kvm_vcpu *vcpu)
{
        struct kvm_segment ldtr;

        vmx_get_segment(vcpu, &ldtr, VCPU_SREG_LDTR);

        if (ldtr.unusable)
                return true;
        if (ldtr.selector & SEGMENT_TI_MASK)    /* TI = 1 */
                return false;
        if (ldtr.type != 2)
                return false;
        if (!ldtr.present)
                return false;

        return true;
}

static bool cs_ss_rpl_check(struct kvm_vcpu *vcpu)
{
        struct kvm_segment cs, ss;

        vmx_get_segment(vcpu, &cs, VCPU_SREG_CS);
        vmx_get_segment(vcpu, &ss, VCPU_SREG_SS);

        return ((cs.selector & SEGMENT_RPL_MASK) ==
                 (ss.selector & SEGMENT_RPL_MASK));
}

/*
 * Check if guest state is valid. Returns true if valid, false if
 * not.
 * We assume that registers are always usable
 */
bool __vmx_guest_state_valid(struct kvm_vcpu *vcpu)
{
        /* real mode guest state checks */
        if (!is_protmode(vcpu) || (vmx_get_rflags(vcpu) & X86_EFLAGS_VM)) {
                if (!rmode_segment_valid(vcpu, VCPU_SREG_CS))
                        return false;
                if (!rmode_segment_valid(vcpu, VCPU_SREG_SS))
                        return false;
                if (!rmode_segment_valid(vcpu, VCPU_SREG_DS))
                        return false;
                if (!rmode_segment_valid(vcpu, VCPU_SREG_ES))
                        return false;
                if (!rmode_segment_valid(vcpu, VCPU_SREG_FS))
                        return false;
                if (!rmode_segment_valid(vcpu, VCPU_SREG_GS))
                        return false;
        } else {
        /* protected mode guest state checks */
                if (!cs_ss_rpl_check(vcpu))
                        return false;
                if (!code_segment_valid(vcpu))
                        return false;
                if (!stack_segment_valid(vcpu))
                        return false;
                if (!data_segment_valid(vcpu, VCPU_SREG_DS))
                        return false;
                if (!data_segment_valid(vcpu, VCPU_SREG_ES))
                        return false;
                if (!data_segment_valid(vcpu, VCPU_SREG_FS))
                        return false;
                if (!data_segment_valid(vcpu, VCPU_SREG_GS))
                        return false;
                if (!tr_valid(vcpu))
                        return false;
                if (!ldtr_valid(vcpu))
                        return false;
        }
        /* TODO:
         * - Add checks on RIP
         * - Add checks on RFLAGS
         */

        return true;
}

static int init_rmode_tss(struct kvm *kvm)
{
        gfn_t fn;
        u16 data = 0;
        int idx, r;

        idx = srcu_read_lock(&kvm->srcu);
        fn = to_kvm_vmx(kvm)->tss_addr >> PAGE_SHIFT;
        r = kvm_clear_guest_page(kvm, fn, 0, PAGE_SIZE);
        if (r < 0)
                goto out;
        data = TSS_BASE_SIZE + TSS_REDIRECTION_SIZE;
        r = kvm_write_guest_page(kvm, fn++, &data,
                        TSS_IOPB_BASE_OFFSET, sizeof(u16));
        if (r < 0)
                goto out;
        r = kvm_clear_guest_page(kvm, fn++, 0, PAGE_SIZE);
        if (r < 0)
                goto out;
        r = kvm_clear_guest_page(kvm, fn, 0, PAGE_SIZE);
        if (r < 0)
                goto out;
        data = ~0;
        r = kvm_write_guest_page(kvm, fn, &data,
                                 RMODE_TSS_SIZE - 2 * PAGE_SIZE - 1,
                                 sizeof(u8));
out:
        srcu_read_unlock(&kvm->srcu, idx);
        return r;
}

static int init_rmode_identity_map(struct kvm *kvm)
{
        struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);
        int i, r = 0;
        kvm_pfn_t identity_map_pfn;
        u32 tmp;

        /* Protect kvm_vmx->ept_identity_pagetable_done. */
        mutex_lock(&kvm->slots_lock);

        if (likely(kvm_vmx->ept_identity_pagetable_done))
                goto out;

        if (!kvm_vmx->ept_identity_map_addr)
                kvm_vmx->ept_identity_map_addr = VMX_EPT_IDENTITY_PAGETABLE_ADDR;
        identity_map_pfn = kvm_vmx->ept_identity_map_addr >> PAGE_SHIFT;

        r = __x86_set_memory_region(kvm, IDENTITY_PAGETABLE_PRIVATE_MEMSLOT,
                                    kvm_vmx->ept_identity_map_addr, PAGE_SIZE);
        if (r < 0)
                goto out;

        r = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE);
        if (r < 0)
                goto out;
        /* Set up identity-mapping pagetable for EPT in real mode */
        for (i = 0; i < PT32_ENT_PER_PAGE; i++) {
                tmp = (i << 22) + (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |
                        _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE);
                r = kvm_write_guest_page(kvm, identity_map_pfn,
                                &tmp, i * sizeof(tmp), sizeof(tmp));
                if (r < 0)
                        goto out;
        }
        kvm_vmx->ept_identity_pagetable_done = true;

out:
        mutex_unlock(&kvm->slots_lock);
        return r;
}

static void seg_setup(int seg)
{
        const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
        unsigned int ar;

        vmcs_write16(sf->selector, 0);
        vmcs_writel(sf->base, 0);
        vmcs_write32(sf->limit, 0xffff);
        ar = 0x93;
        if (seg == VCPU_SREG_CS)
                ar |= 0x08; /* code segment */

        vmcs_write32(sf->ar_bytes, ar);
}

static int alloc_apic_access_page(struct kvm *kvm)
{
        struct page *page;
        int r = 0;

        mutex_lock(&kvm->slots_lock);
        if (kvm->arch.apic_access_page_done)
                goto out;
        r = __x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
                                    APIC_DEFAULT_PHYS_BASE, PAGE_SIZE);
        if (r)
                goto out;

        page = gfn_to_page(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT);
        if (is_error_page(page)) {
                r = -EFAULT;
                goto out;
        }

        /*
         * Do not pin the page in memory, so that memory hot-unplug
         * is able to migrate it.
         */
        put_page(page);
        kvm->arch.apic_access_page_done = true;
out:
        mutex_unlock(&kvm->slots_lock);
        return r;
}

int allocate_vpid(void)
{
        int vpid;

        if (!enable_vpid)
                return 0;
        spin_lock(&vmx_vpid_lock);
        vpid = find_first_zero_bit(vmx_vpid_bitmap, VMX_NR_VPIDS);
        if (vpid < VMX_NR_VPIDS)
                __set_bit(vpid, vmx_vpid_bitmap);
        else
                vpid = 0;
        spin_unlock(&vmx_vpid_lock);
        return vpid;
}

void free_vpid(int vpid)
{
        if (!enable_vpid || vpid == 0)
                return;
        spin_lock(&vmx_vpid_lock);
        __clear_bit(vpid, vmx_vpid_bitmap);
        spin_unlock(&vmx_vpid_lock);
}

static __always_inline void vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
                                                          u32 msr, int type)
{
        int f = sizeof(unsigned long);

        if (!cpu_has_vmx_msr_bitmap())
                return;

        if (static_branch_unlikely(&enable_evmcs))
                evmcs_touch_msr_bitmap();

        /*
         * See Intel PRM Vol. 3, 20.6.9 (MSR-Bitmap Address). Early manuals
         * have the write-low and read-high bitmap offsets the wrong way round.
         * We can control MSRs 0x00000000-0x00001fff and 0xc0000000-0xc0001fff.
         */
        if (msr <= 0x1fff) {
                if (type & MSR_TYPE_R)
                        /* read-low */
                        __clear_bit(msr, msr_bitmap + 0x000 / f);

                if (type & MSR_TYPE_W)
                        /* write-low */
                        __clear_bit(msr, msr_bitmap + 0x800 / f);

        } else if ((msr >= 0xc0000000) && (msr <= 0xc0001fff)) {
                msr &= 0x1fff;
                if (type & MSR_TYPE_R)
                        /* read-high */
                        __clear_bit(msr, msr_bitmap + 0x400 / f);

                if (type & MSR_TYPE_W)
                        /* write-high */
                        __clear_bit(msr, msr_bitmap + 0xc00 / f);

        }
}

static __always_inline void vmx_enable_intercept_for_msr(unsigned long *msr_bitmap,
                                                         u32 msr, int type)
{
        int f = sizeof(unsigned long);

        if (!cpu_has_vmx_msr_bitmap())
                return;

        if (static_branch_unlikely(&enable_evmcs))
                evmcs_touch_msr_bitmap();

        /*
         * See Intel PRM Vol. 3, 20.6.9 (MSR-Bitmap Address). Early manuals
         * have the write-low and read-high bitmap offsets the wrong way round.
         * We can control MSRs 0x00000000-0x00001fff and 0xc0000000-0xc0001fff.
         */
        if (msr <= 0x1fff) {
                if (type & MSR_TYPE_R)
                        /* read-low */
                        __set_bit(msr, msr_bitmap + 0x000 / f);

                if (type & MSR_TYPE_W)
                        /* write-low */
                        __set_bit(msr, msr_bitmap + 0x800 / f);

        } else if ((msr >= 0xc0000000) && (msr <= 0xc0001fff)) {
                msr &= 0x1fff;
                if (type & MSR_TYPE_R)
                        /* read-high */
                        __set_bit(msr, msr_bitmap + 0x400 / f);

                if (type & MSR_TYPE_W)
                        /* write-high */
                        __set_bit(msr, msr_bitmap + 0xc00 / f);

        }
}

static __always_inline void vmx_set_intercept_for_msr(unsigned long *msr_bitmap,
                                                      u32 msr, int type, bool value)
{
        if (value)
                vmx_enable_intercept_for_msr(msr_bitmap, msr, type);
        else
                vmx_disable_intercept_for_msr(msr_bitmap, msr, type);
}

static u8 vmx_msr_bitmap_mode(struct kvm_vcpu *vcpu)
{
        u8 mode = 0;

        if (cpu_has_secondary_exec_ctrls() &&
            (secondary_exec_controls_get(to_vmx(vcpu)) &
             SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) {
                mode |= MSR_BITMAP_MODE_X2APIC;
                if (enable_apicv && kvm_vcpu_apicv_active(vcpu))
                        mode |= MSR_BITMAP_MODE_X2APIC_APICV;
        }

        return mode;
}

static void vmx_update_msr_bitmap_x2apic(unsigned long *msr_bitmap,
                                         u8 mode)
{
        int msr;

        for (msr = 0x800; msr <= 0x8ff; msr += BITS_PER_LONG) {
                unsigned word = msr / BITS_PER_LONG;
                msr_bitmap[word] = (mode & MSR_BITMAP_MODE_X2APIC_APICV) ? 0 : ~0;
                msr_bitmap[word + (0x800 / sizeof(long))] = ~0;
        }

        if (mode & MSR_BITMAP_MODE_X2APIC) {
                /*
                 * TPR reads and writes can be virtualized even if virtual interrupt
                 * delivery is not in use.
                 */
                vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_TASKPRI), MSR_TYPE_RW);
                if (mode & MSR_BITMAP_MODE_X2APIC_APICV) {
                        vmx_enable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_TMCCT), MSR_TYPE_R);
                        vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_EOI), MSR_TYPE_W);
                        vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_SELF_IPI), MSR_TYPE_W);
                }
        }
}

void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;
        u8 mode = vmx_msr_bitmap_mode(vcpu);
        u8 changed = mode ^ vmx->msr_bitmap_mode;

        if (!changed)
                return;

        if (changed & (MSR_BITMAP_MODE_X2APIC | MSR_BITMAP_MODE_X2APIC_APICV))
                vmx_update_msr_bitmap_x2apic(msr_bitmap, mode);

        vmx->msr_bitmap_mode = mode;
}

void pt_update_intercept_for_msr(struct vcpu_vmx *vmx)
{
        unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;
        bool flag = !(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN);
        u32 i;

        vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_STATUS,
                                                        MSR_TYPE_RW, flag);
        vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_OUTPUT_BASE,
                                                        MSR_TYPE_RW, flag);
        vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_OUTPUT_MASK,
                                                        MSR_TYPE_RW, flag);
        vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_CR3_MATCH,
                                                        MSR_TYPE_RW, flag);
        for (i = 0; i < vmx->pt_desc.addr_range; i++) {
                vmx_set_intercept_for_msr(msr_bitmap,
                        MSR_IA32_RTIT_ADDR0_A + i * 2, MSR_TYPE_RW, flag);
                vmx_set_intercept_for_msr(msr_bitmap,
                        MSR_IA32_RTIT_ADDR0_B + i * 2, MSR_TYPE_RW, flag);
        }
}

static bool vmx_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        void *vapic_page;
        u32 vppr;
        int rvi;

        if (WARN_ON_ONCE(!is_guest_mode(vcpu)) ||
                !nested_cpu_has_vid(get_vmcs12(vcpu)) ||
                WARN_ON_ONCE(!vmx->nested.virtual_apic_map.gfn))
                return false;

        rvi = vmx_get_rvi();

        vapic_page = vmx->nested.virtual_apic_map.hva;
        vppr = *((u32 *)(vapic_page + APIC_PROCPRI));

        return ((rvi & 0xf0) > (vppr & 0xf0));
}

static inline bool kvm_vcpu_trigger_posted_interrupt(struct kvm_vcpu *vcpu,
                                                     bool nested)
{
#ifdef CONFIG_SMP
        int pi_vec = nested ? POSTED_INTR_NESTED_VECTOR : POSTED_INTR_VECTOR;

        if (vcpu->mode == IN_GUEST_MODE) {
                /*
                 * The vector of interrupt to be delivered to vcpu had
                 * been set in PIR before this function.
                 *
                 * Following cases will be reached in this block, and
                 * we always send a notification event in all cases as
                 * explained below.
                 *
                 * Case 1: vcpu keeps in non-root mode. Sending a
                 * notification event posts the interrupt to vcpu.
                 *
                 * Case 2: vcpu exits to root mode and is still
                 * runnable. PIR will be synced to vIRR before the
                 * next vcpu entry. Sending a notification event in
                 * this case has no effect, as vcpu is not in root
                 * mode.
                 *
                 * Case 3: vcpu exits to root mode and is blocked.
                 * vcpu_block() has already synced PIR to vIRR and
                 * never blocks vcpu if vIRR is not cleared. Therefore,
                 * a blocked vcpu here does not wait for any requested
                 * interrupts in PIR, and sending a notification event
                 * which has no effect is safe here.
                 */

                apic->send_IPI_mask(get_cpu_mask(vcpu->cpu), pi_vec);
                return true;
        }
#endif
        return false;
}

static int vmx_deliver_nested_posted_interrupt(struct kvm_vcpu *vcpu,
                                                int vector)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (is_guest_mode(vcpu) &&
            vector == vmx->nested.posted_intr_nv) {
                /*
                 * If a posted intr is not recognized by hardware,
                 * we will accomplish it in the next vmentry.
                 */
                vmx->nested.pi_pending = true;
                kvm_make_request(KVM_REQ_EVENT, vcpu);
                /* the PIR and ON have been set by L1. */
                if (!kvm_vcpu_trigger_posted_interrupt(vcpu, true))
                        kvm_vcpu_kick(vcpu);
                return 0;
        }
        return -1;
}
/*
 * Send interrupt to vcpu via posted interrupt way.
 * 1. If target vcpu is running(non-root mode), send posted interrupt
 * notification to vcpu and hardware will sync PIR to vIRR atomically.
 * 2. If target vcpu isn't running(root mode), kick it to pick up the
 * interrupt from PIR in next vmentry.
 */
static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        int r;

        r = vmx_deliver_nested_posted_interrupt(vcpu, vector);
        if (!r)
                return 0;

        if (!vcpu->arch.apicv_active)
                return -1;

        if (pi_test_and_set_pir(vector, &vmx->pi_desc))
                return 0;

        /* If a previous notification has sent the IPI, nothing to do.  */
        if (pi_test_and_set_on(&vmx->pi_desc))
                return 0;

        if (vcpu != kvm_get_running_vcpu() &&
            !kvm_vcpu_trigger_posted_interrupt(vcpu, false))
                kvm_vcpu_kick(vcpu);

        return 0;
}

/*
 * Set up the vmcs's constant host-state fields, i.e., host-state fields that
 * will not change in the lifetime of the guest.
 * Note that host-state that does change is set elsewhere. E.g., host-state
 * that is set differently for each CPU is set in vmx_vcpu_load(), not here.
 */
void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
{
        u32 low32, high32;
        unsigned long tmpl;
        unsigned long cr0, cr3, cr4;

        cr0 = read_cr0();
        WARN_ON(cr0 & X86_CR0_TS);
        vmcs_writel(HOST_CR0, cr0);  /* 22.2.3 */

        /*
         * Save the most likely value for this task's CR3 in the VMCS.
         * We can't use __get_current_cr3_fast() because we're not atomic.
         */
        cr3 = __read_cr3();
        vmcs_writel(HOST_CR3, cr3);             /* 22.2.3  FIXME: shadow tables */
        vmx->loaded_vmcs->host_state.cr3 = cr3;

        /* Save the most likely value for this task's CR4 in the VMCS. */
        cr4 = cr4_read_shadow();
        vmcs_writel(HOST_CR4, cr4);                     /* 22.2.3, 22.2.5 */
        vmx->loaded_vmcs->host_state.cr4 = cr4;

        vmcs_write16(HOST_CS_SELECTOR, __KERNEL_CS);  /* 22.2.4 */
#ifdef CONFIG_X86_64
        /*
         * Load null selectors, so we can avoid reloading them in
         * vmx_prepare_switch_to_host(), in case userspace uses
         * the null selectors too (the expected case).
         */
        vmcs_write16(HOST_DS_SELECTOR, 0);
        vmcs_write16(HOST_ES_SELECTOR, 0);
#else
        vmcs_write16(HOST_DS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
        vmcs_write16(HOST_ES_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
#endif
        vmcs_write16(HOST_SS_SELECTOR, __KERNEL_DS);  /* 22.2.4 */
        vmcs_write16(HOST_TR_SELECTOR, GDT_ENTRY_TSS*8);  /* 22.2.4 */

        vmcs_writel(HOST_IDTR_BASE, host_idt_base);   /* 22.2.4 */

        vmcs_writel(HOST_RIP, (unsigned long)vmx_vmexit); /* 22.2.5 */

        rdmsr(MSR_IA32_SYSENTER_CS, low32, high32);
        vmcs_write32(HOST_IA32_SYSENTER_CS, low32);
        rdmsrl(MSR_IA32_SYSENTER_EIP, tmpl);
        vmcs_writel(HOST_IA32_SYSENTER_EIP, tmpl);   /* 22.2.3 */

        if (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_IA32_PAT) {
                rdmsr(MSR_IA32_CR_PAT, low32, high32);
                vmcs_write64(HOST_IA32_PAT, low32 | ((u64) high32 << 32));
        }

        if (cpu_has_load_ia32_efer())
                vmcs_write64(HOST_IA32_EFER, host_efer);
}

void set_cr4_guest_host_mask(struct vcpu_vmx *vmx)
{
        vmx->vcpu.arch.cr4_guest_owned_bits = KVM_POSSIBLE_CR4_GUEST_BITS;
        if (!enable_ept)
                vmx->vcpu.arch.cr4_guest_owned_bits &= ~X86_CR4_PGE;
        if (is_guest_mode(&vmx->vcpu))
                vmx->vcpu.arch.cr4_guest_owned_bits &=
                        ~get_vmcs12(&vmx->vcpu)->cr4_guest_host_mask;
        vmcs_writel(CR4_GUEST_HOST_MASK, ~vmx->vcpu.arch.cr4_guest_owned_bits);
}

u32 vmx_pin_based_exec_ctrl(struct vcpu_vmx *vmx)
{
        u32 pin_based_exec_ctrl = vmcs_config.pin_based_exec_ctrl;

        if (!kvm_vcpu_apicv_active(&vmx->vcpu))
                pin_based_exec_ctrl &= ~PIN_BASED_POSTED_INTR;

        if (!enable_vnmi)
                pin_based_exec_ctrl &= ~PIN_BASED_VIRTUAL_NMIS;

        if (!enable_preemption_timer)
                pin_based_exec_ctrl &= ~PIN_BASED_VMX_PREEMPTION_TIMER;

        return pin_based_exec_ctrl;
}

static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        pin_controls_set(vmx, vmx_pin_based_exec_ctrl(vmx));
        if (cpu_has_secondary_exec_ctrls()) {
                if (kvm_vcpu_apicv_active(vcpu))
                        secondary_exec_controls_setbit(vmx,
                                      SECONDARY_EXEC_APIC_REGISTER_VIRT |
                                      SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
                else
                        secondary_exec_controls_clearbit(vmx,
                                        SECONDARY_EXEC_APIC_REGISTER_VIRT |
                                        SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
        }

        if (cpu_has_vmx_msr_bitmap())
                vmx_update_msr_bitmap(vcpu);
}

u32 vmx_exec_control(struct vcpu_vmx *vmx)
{
        u32 exec_control = vmcs_config.cpu_based_exec_ctrl;

        if (vmx->vcpu.arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)
                exec_control &= ~CPU_BASED_MOV_DR_EXITING;

        if (!cpu_need_tpr_shadow(&vmx->vcpu)) {
                exec_control &= ~CPU_BASED_TPR_SHADOW;
#ifdef CONFIG_X86_64
                exec_control |= CPU_BASED_CR8_STORE_EXITING |
                                CPU_BASED_CR8_LOAD_EXITING;
#endif
        }
        if (!enable_ept)
                exec_control |= CPU_BASED_CR3_STORE_EXITING |
                                CPU_BASED_CR3_LOAD_EXITING  |
                                CPU_BASED_INVLPG_EXITING;
        if (kvm_mwait_in_guest(vmx->vcpu.kvm))
                exec_control &= ~(CPU_BASED_MWAIT_EXITING |
                                CPU_BASED_MONITOR_EXITING);
        if (kvm_hlt_in_guest(vmx->vcpu.kvm))
                exec_control &= ~CPU_BASED_HLT_EXITING;
        return exec_control;
}

/*
 * Adjust a single secondary execution control bit to intercept/allow an
 * instruction in the guest.  This is usually done based on whether or not a
 * feature has been exposed to the guest in order to correctly emulate faults.
 */
static inline void
vmx_adjust_secondary_exec_control(struct vcpu_vmx *vmx, u32 *exec_control,
                                  u32 control, bool enabled, bool exiting)
{
        /*
         * If the control is for an opt-in feature, clear the control if the
         * feature is not exposed to the guest, i.e. not enabled.  If the
         * control is opt-out, i.e. an exiting control, clear the control if
         * the feature _is_ exposed to the guest, i.e. exiting/interception is
         * disabled for the associated instruction.  Note, the caller is
         * responsible presetting exec_control to set all supported bits.
         */
        if (enabled == exiting)
                *exec_control &= ~control;

        /*
         * Update the nested MSR settings so that a nested VMM can/can't set
         * controls for features that are/aren't exposed to the guest.
         */
        if (nested) {
                if (enabled)
                        vmx->nested.msrs.secondary_ctls_high |= control;
                else
                        vmx->nested.msrs.secondary_ctls_high &= ~control;
        }
}

/*
 * Wrapper macro for the common case of adjusting a secondary execution control
 * based on a single guest CPUID bit, with a dedicated feature bit.  This also
 * verifies that the control is actually supported by KVM and hardware.
 */
#define vmx_adjust_sec_exec_control(vmx, exec_control, name, feat_name, ctrl_name, exiting) \
({                                                                       \
        bool __enabled;                                                  \
                                                                         \
        if (cpu_has_vmx_##name()) {                                      \
                __enabled = guest_cpuid_has(&(vmx)->vcpu,                \
                                            X86_FEATURE_##feat_name);    \
                vmx_adjust_secondary_exec_control(vmx, exec_control,     \
                        SECONDARY_EXEC_##ctrl_name, __enabled, exiting); \
        }                                                                \
})

/* More macro magic for ENABLE_/opt-in versus _EXITING/opt-out controls. */
#define vmx_adjust_sec_exec_feature(vmx, exec_control, lname, uname) \
        vmx_adjust_sec_exec_control(vmx, exec_control, lname, uname, ENABLE_##uname, false)

#define vmx_adjust_sec_exec_exiting(vmx, exec_control, lname, uname) \
        vmx_adjust_sec_exec_control(vmx, exec_control, lname, uname, uname##_EXITING, true)

static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx)
{
        struct kvm_vcpu *vcpu = &vmx->vcpu;

        u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;

        if (vmx_pt_mode_is_system())
                exec_control &= ~(SECONDARY_EXEC_PT_USE_GPA | SECONDARY_EXEC_PT_CONCEAL_VMX);
        if (!cpu_need_virtualize_apic_accesses(vcpu))
                exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
        if (vmx->vpid == 0)
                exec_control &= ~SECONDARY_EXEC_ENABLE_VPID;
        if (!enable_ept) {
                exec_control &= ~SECONDARY_EXEC_ENABLE_EPT;
                enable_unrestricted_guest = 0;
        }
        if (!enable_unrestricted_guest)
                exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST;
        if (kvm_pause_in_guest(vmx->vcpu.kvm))
                exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING;
        if (!kvm_vcpu_apicv_active(vcpu))
                exec_control &= ~(SECONDARY_EXEC_APIC_REGISTER_VIRT |
                                  SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
        exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE;

        /* SECONDARY_EXEC_DESC is enabled/disabled on writes to CR4.UMIP,
         * in vmx_set_cr4.  */
        exec_control &= ~SECONDARY_EXEC_DESC;

        /* SECONDARY_EXEC_SHADOW_VMCS is enabled when L1 executes VMPTRLD
           (handle_vmptrld).
           We can NOT enable shadow_vmcs here because we don't have yet
           a current VMCS12
        */
        exec_control &= ~SECONDARY_EXEC_SHADOW_VMCS;

        if (!enable_pml)
                exec_control &= ~SECONDARY_EXEC_ENABLE_PML;

        if (cpu_has_vmx_xsaves()) {
                /* Exposing XSAVES only when XSAVE is exposed */
                bool xsaves_enabled =
                        boot_cpu_has(X86_FEATURE_XSAVE) &&
                        guest_cpuid_has(vcpu, X86_FEATURE_XSAVE) &&
                        guest_cpuid_has(vcpu, X86_FEATURE_XSAVES);

                vcpu->arch.xsaves_enabled = xsaves_enabled;

                vmx_adjust_secondary_exec_control(vmx, &exec_control,
                                                  SECONDARY_EXEC_XSAVES,
                                                  xsaves_enabled, false);
        }

        vmx_adjust_sec_exec_feature(vmx, &exec_control, rdtscp, RDTSCP);

        /*
         * Expose INVPCID if and only if PCID is also exposed to the guest.
         * INVPCID takes a #UD when it's disabled in the VMCS, but a #GP or #PF
         * if CR4.PCIDE=0.  Enumerating CPUID.INVPCID=1 would lead to incorrect
         * behavior from the guest perspective (it would expect #GP or #PF).
         */
        if (!guest_cpuid_has(vcpu, X86_FEATURE_PCID))
                guest_cpuid_clear(vcpu, X86_FEATURE_INVPCID);
        vmx_adjust_sec_exec_feature(vmx, &exec_control, invpcid, INVPCID);


        vmx_adjust_sec_exec_exiting(vmx, &exec_control, rdrand, RDRAND);
        vmx_adjust_sec_exec_exiting(vmx, &exec_control, rdseed, RDSEED);

        vmx_adjust_sec_exec_control(vmx, &exec_control, waitpkg, WAITPKG,
                                    ENABLE_USR_WAIT_PAUSE, false);

        vmx->secondary_exec_control = exec_control;
}

static void ept_set_mmio_spte_mask(void)
{
        /*
         * EPT Misconfigurations can be generated if the value of bits 2:0
         * of an EPT paging-structure entry is 110b (write/execute).
         */
        kvm_mmu_set_mmio_spte_mask(VMX_EPT_MISCONFIG_WX_VALUE, 0);
}

#define VMX_XSS_EXIT_BITMAP 0

/*
 * Noting that the initialization of Guest-state Area of VMCS is in
 * vmx_vcpu_reset().
 */
static void init_vmcs(struct vcpu_vmx *vmx)
{
        if (nested)
                nested_vmx_set_vmcs_shadowing_bitmap();

        if (cpu_has_vmx_msr_bitmap())
                vmcs_write64(MSR_BITMAP, __pa(vmx->vmcs01.msr_bitmap));

        vmcs_write64(VMCS_LINK_POINTER, -1ull); /* 22.3.1.5 */

        /* Control */
        pin_controls_set(vmx, vmx_pin_based_exec_ctrl(vmx));

        exec_controls_set(vmx, vmx_exec_control(vmx));

        if (cpu_has_secondary_exec_ctrls()) {
                vmx_compute_secondary_exec_control(vmx);
                secondary_exec_controls_set(vmx, vmx->secondary_exec_control);
        }

        if (kvm_vcpu_apicv_active(&vmx->vcpu)) {
                vmcs_write64(EOI_EXIT_BITMAP0, 0);
                vmcs_write64(EOI_EXIT_BITMAP1, 0);
                vmcs_write64(EOI_EXIT_BITMAP2, 0);
                vmcs_write64(EOI_EXIT_BITMAP3, 0);

                vmcs_write16(GUEST_INTR_STATUS, 0);

                vmcs_write16(POSTED_INTR_NV, POSTED_INTR_VECTOR);
                vmcs_write64(POSTED_INTR_DESC_ADDR, __pa((&vmx->pi_desc)));
        }

        if (!kvm_pause_in_guest(vmx->vcpu.kvm)) {
                vmcs_write32(PLE_GAP, ple_gap);
                vmx->ple_window = ple_window;
                vmx->ple_window_dirty = true;
        }

        vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, 0);
        vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, 0);
        vmcs_write32(CR3_TARGET_COUNT, 0);           /* 22.2.1 */

        vmcs_write16(HOST_FS_SELECTOR, 0);            /* 22.2.4 */
        vmcs_write16(HOST_GS_SELECTOR, 0);            /* 22.2.4 */
        vmx_set_constant_host_state(vmx);
        vmcs_writel(HOST_FS_BASE, 0); /* 22.2.4 */
        vmcs_writel(HOST_GS_BASE, 0); /* 22.2.4 */

        if (cpu_has_vmx_vmfunc())
                vmcs_write64(VM_FUNCTION_CONTROL, 0);

        vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0);
        vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0);
        vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host.val));
        vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, 0);
        vmcs_write64(VM_ENTRY_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.guest.val));

        if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
                vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat);

        vm_exit_controls_set(vmx, vmx_vmexit_ctrl());

        /* 22.2.1, 20.8.1 */
        vm_entry_controls_set(vmx, vmx_vmentry_ctrl());

        vmx->vcpu.arch.cr0_guest_owned_bits = KVM_POSSIBLE_CR0_GUEST_BITS;
        vmcs_writel(CR0_GUEST_HOST_MASK, ~vmx->vcpu.arch.cr0_guest_owned_bits);

        set_cr4_guest_host_mask(vmx);

        if (vmx->vpid != 0)
                vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid);

        if (cpu_has_vmx_xsaves())
                vmcs_write64(XSS_EXIT_BITMAP, VMX_XSS_EXIT_BITMAP);

        if (enable_pml) {
                vmcs_write64(PML_ADDRESS, page_to_phys(vmx->pml_pg));
                vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1);
        }

        if (cpu_has_vmx_encls_vmexit())
                vmcs_write64(ENCLS_EXITING_BITMAP, -1ull);

        if (vmx_pt_mode_is_host_guest()) {
                memset(&vmx->pt_desc, 0, sizeof(vmx->pt_desc));
                /* Bit[6~0] are forced to 1, writes are ignored. */
                vmx->pt_desc.guest.output_mask = 0x7F;
                vmcs_write64(GUEST_IA32_RTIT_CTL, 0);
        }

        /*
         * If EPT is enabled, #PF is only trapped if MAXPHYADDR is mismatched
         * between guest and host.  In that case we only care about present
         * faults.
         */
        if (enable_ept) {
                vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, PFERR_PRESENT_MASK);
                vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, PFERR_PRESENT_MASK);
        }
}

static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct msr_data apic_base_msr;
        u64 cr0;

        vmx->rmode.vm86_active = 0;
        vmx->spec_ctrl = 0;

        vmx->msr_ia32_umwait_control = 0;

        vmx->vcpu.arch.regs[VCPU_REGS_RDX] = get_rdx_init_val();
        vmx->hv_deadline_tsc = -1;
        kvm_set_cr8(vcpu, 0);

        if (!init_event) {
                apic_base_msr.data = APIC_DEFAULT_PHYS_BASE |
                                     MSR_IA32_APICBASE_ENABLE;
                if (kvm_vcpu_is_reset_bsp(vcpu))
                        apic_base_msr.data |= MSR_IA32_APICBASE_BSP;
                apic_base_msr.host_initiated = true;
                kvm_set_apic_base(vcpu, &apic_base_msr);
        }

        vmx_segment_cache_clear(vmx);

        seg_setup(VCPU_SREG_CS);
        vmcs_write16(GUEST_CS_SELECTOR, 0xf000);
        vmcs_writel(GUEST_CS_BASE, 0xffff0000ul);

        seg_setup(VCPU_SREG_DS);
        seg_setup(VCPU_SREG_ES);
        seg_setup(VCPU_SREG_FS);
        seg_setup(VCPU_SREG_GS);
        seg_setup(VCPU_SREG_SS);

        vmcs_write16(GUEST_TR_SELECTOR, 0);
        vmcs_writel(GUEST_TR_BASE, 0);
        vmcs_write32(GUEST_TR_LIMIT, 0xffff);
        vmcs_write32(GUEST_TR_AR_BYTES, 0x008b);

        vmcs_write16(GUEST_LDTR_SELECTOR, 0);
        vmcs_writel(GUEST_LDTR_BASE, 0);
        vmcs_write32(GUEST_LDTR_LIMIT, 0xffff);
        vmcs_write32(GUEST_LDTR_AR_BYTES, 0x00082);

        if (!init_event) {
                vmcs_write32(GUEST_SYSENTER_CS, 0);
                vmcs_writel(GUEST_SYSENTER_ESP, 0);
                vmcs_writel(GUEST_SYSENTER_EIP, 0);
                vmcs_write64(GUEST_IA32_DEBUGCTL, 0);
        }

        kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
        kvm_rip_write(vcpu, 0xfff0);

        vmcs_writel(GUEST_GDTR_BASE, 0);
        vmcs_write32(GUEST_GDTR_LIMIT, 0xffff);

        vmcs_writel(GUEST_IDTR_BASE, 0);
        vmcs_write32(GUEST_IDTR_LIMIT, 0xffff);

        vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE);
        vmcs_write32(GUEST_INTERRUPTIBILITY_INFO, 0);
        vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS, 0);
        if (kvm_mpx_supported())
                vmcs_write64(GUEST_BNDCFGS, 0);

        setup_msrs(vmx);

        vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, 0);  /* 22.2.1 */

        if (cpu_has_vmx_tpr_shadow() && !init_event) {
                vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, 0);
                if (cpu_need_tpr_shadow(vcpu))
                        vmcs_write64(VIRTUAL_APIC_PAGE_ADDR,
                                     __pa(vcpu->arch.apic->regs));
                vmcs_write32(TPR_THRESHOLD, 0);
        }

        kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu);

        cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET;
        vmx->vcpu.arch.cr0 = cr0;
        vmx_set_cr0(vcpu, cr0); /* enter rmode */
        vmx_set_cr4(vcpu, 0);
        vmx_set_efer(vcpu, 0);

        update_exception_bitmap(vcpu);

        vpid_sync_context(vmx->vpid);
        if (init_event)
                vmx_clear_hlt(vcpu);
}

static void enable_irq_window(struct kvm_vcpu *vcpu)
{
        exec_controls_setbit(to_vmx(vcpu), CPU_BASED_INTR_WINDOW_EXITING);
}

static void enable_nmi_window(struct kvm_vcpu *vcpu)
{
        if (!enable_vnmi ||
            vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_STI) {
                enable_irq_window(vcpu);
                return;
        }

        exec_controls_setbit(to_vmx(vcpu), CPU_BASED_NMI_WINDOW_EXITING);
}

static void vmx_inject_irq(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        uint32_t intr;
        int irq = vcpu->arch.interrupt.nr;

        trace_kvm_inj_virq(irq);

        ++vcpu->stat.irq_injections;
        if (vmx->rmode.vm86_active) {
                int inc_eip = 0;
                if (vcpu->arch.interrupt.soft)
                        inc_eip = vcpu->arch.event_exit_inst_len;
                kvm_inject_realmode_interrupt(vcpu, irq, inc_eip);
                return;
        }
        intr = irq | INTR_INFO_VALID_MASK;
        if (vcpu->arch.interrupt.soft) {
                intr |= INTR_TYPE_SOFT_INTR;
                vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
                             vmx->vcpu.arch.event_exit_inst_len);
        } else
                intr |= INTR_TYPE_EXT_INTR;
        vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, intr);

        vmx_clear_hlt(vcpu);
}

static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (!enable_vnmi) {
                /*
                 * Tracking the NMI-blocked state in software is built upon
                 * finding the next open IRQ window. This, in turn, depends on
                 * well-behaving guests: They have to keep IRQs disabled at
                 * least as long as the NMI handler runs. Otherwise we may
                 * cause NMI nesting, maybe breaking the guest. But as this is
                 * highly unlikely, we can live with the residual risk.
                 */
                vmx->loaded_vmcs->soft_vnmi_blocked = 1;
                vmx->loaded_vmcs->vnmi_blocked_time = 0;
        }

        ++vcpu->stat.nmi_injections;
        vmx->loaded_vmcs->nmi_known_unmasked = false;

        if (vmx->rmode.vm86_active) {
                kvm_inject_realmode_interrupt(vcpu, NMI_VECTOR, 0);
                return;
        }

        vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
                        INTR_TYPE_NMI_INTR | INTR_INFO_VALID_MASK | NMI_VECTOR);

        vmx_clear_hlt(vcpu);
}

bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        bool masked;

        if (!enable_vnmi)
                return vmx->loaded_vmcs->soft_vnmi_blocked;
        if (vmx->loaded_vmcs->nmi_known_unmasked)
                return false;
        masked = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_NMI;
        vmx->loaded_vmcs->nmi_known_unmasked = !masked;
        return masked;
}

void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (!enable_vnmi) {
                if (vmx->loaded_vmcs->soft_vnmi_blocked != masked) {
                        vmx->loaded_vmcs->soft_vnmi_blocked = masked;
                        vmx->loaded_vmcs->vnmi_blocked_time = 0;
                }
        } else {
                vmx->loaded_vmcs->nmi_known_unmasked = !masked;
                if (masked)
                        vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
                                      GUEST_INTR_STATE_NMI);
                else
                        vmcs_clear_bits(GUEST_INTERRUPTIBILITY_INFO,
                                        GUEST_INTR_STATE_NMI);
        }
}

bool vmx_nmi_blocked(struct kvm_vcpu *vcpu)
{
        if (is_guest_mode(vcpu) && nested_exit_on_nmi(vcpu))
                return false;

        if (!enable_vnmi && to_vmx(vcpu)->loaded_vmcs->soft_vnmi_blocked)
                return true;

        return (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
                (GUEST_INTR_STATE_MOV_SS | GUEST_INTR_STATE_STI |
                 GUEST_INTR_STATE_NMI));
}

static int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
        if (to_vmx(vcpu)->nested.nested_run_pending)
                return -EBUSY;

        /* An NMI must not be injected into L2 if it's supposed to VM-Exit.  */
        if (for_injection && is_guest_mode(vcpu) && nested_exit_on_nmi(vcpu))
                return -EBUSY;

        return !vmx_nmi_blocked(vcpu);
}

bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
{
        if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
                return false;

        return !(vmx_get_rflags(vcpu) & X86_EFLAGS_IF) ||
               (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
                (GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));
}

static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
        if (to_vmx(vcpu)->nested.nested_run_pending)
                return -EBUSY;

       /*
        * An IRQ must not be injected into L2 if it's supposed to VM-Exit,
        * e.g. if the IRQ arrived asynchronously after checking nested events.
        */
        if (for_injection && is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
                return -EBUSY;

        return !vmx_interrupt_blocked(vcpu);
}

static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
{
        int ret;

        if (enable_unrestricted_guest)
                return 0;

        mutex_lock(&kvm->slots_lock);
        ret = __x86_set_memory_region(kvm, TSS_PRIVATE_MEMSLOT, addr,
                                      PAGE_SIZE * 3);
        mutex_unlock(&kvm->slots_lock);

        if (ret)
                return ret;
        to_kvm_vmx(kvm)->tss_addr = addr;
        return init_rmode_tss(kvm);
}

static int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr)
{
        to_kvm_vmx(kvm)->ept_identity_map_addr = ident_addr;
        return 0;
}

static bool rmode_exception(struct kvm_vcpu *vcpu, int vec)
{
        switch (vec) {
        case BP_VECTOR:
                /*
                 * Update instruction length as we may reinject the exception
                 * from user space while in guest debugging mode.
                 */
                to_vmx(vcpu)->vcpu.arch.event_exit_inst_len =
                        vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
                if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP)
                        return false;
                fallthrough;
        case DB_VECTOR:
                return !(vcpu->guest_debug &
                        (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP));
        case DE_VECTOR:
        case OF_VECTOR:
        case BR_VECTOR:
        case UD_VECTOR:
        case DF_VECTOR:
        case SS_VECTOR:
        case GP_VECTOR:
        case MF_VECTOR:
                return true;
        }
        return false;
}

static int handle_rmode_exception(struct kvm_vcpu *vcpu,
                                  int vec, u32 err_code)
{
        /*
         * Instruction with address size override prefix opcode 0x67
         * Cause the #SS fault with 0 error code in VM86 mode.
         */
        if (((vec == GP_VECTOR) || (vec == SS_VECTOR)) && err_code == 0) {
                if (kvm_emulate_instruction(vcpu, 0)) {
                        if (vcpu->arch.halt_request) {
                                vcpu->arch.halt_request = 0;
                                return kvm_vcpu_halt(vcpu);
                        }
                        return 1;
                }
                return 0;
        }

        /*
         * Forward all other exceptions that are valid in real mode.
         * FIXME: Breaks guest debugging in real mode, needs to be fixed with
         *        the required debugging infrastructure rework.
         */
        kvm_queue_exception(vcpu, vec);
        return 1;
}

/*
 * Trigger machine check on the host. We assume all the MSRs are already set up
 * by the CPU and that we still run on the same CPU as the MCE occurred on.
 * We pass a fake environment to the machine check handler because we want
 * the guest to be always treated like user space, no matter what context
 * it used internally.
 */
static void kvm_machine_check(void)
{
#if defined(CONFIG_X86_MCE)
        struct pt_regs regs = {
                .cs = 3, /* Fake ring 3 no matter what the guest ran on */
                .flags = X86_EFLAGS_IF,
        };

        do_machine_check(&regs);
#endif
}

static int handle_machine_check(struct kvm_vcpu *vcpu)
{
        /* handled by vmx_vcpu_run() */
        return 1;
}

/*
 * If the host has split lock detection disabled, then #AC is
 * unconditionally injected into the guest, which is the pre split lock
 * detection behaviour.
 *
 * If the host has split lock detection enabled then #AC is
 * only injected into the guest when:
 *  - Guest CPL == 3 (user mode)
 *  - Guest has #AC detection enabled in CR0
 *  - Guest EFLAGS has AC bit set
 */
static inline bool guest_inject_ac(struct kvm_vcpu *vcpu)
{
        if (!boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
                return true;

        return vmx_get_cpl(vcpu) == 3 && kvm_read_cr0_bits(vcpu, X86_CR0_AM) &&
               (kvm_get_rflags(vcpu) & X86_EFLAGS_AC);
}

static int handle_exception_nmi(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct kvm_run *kvm_run = vcpu->run;
        u32 intr_info, ex_no, error_code;
        unsigned long cr2, rip, dr6;
        u32 vect_info;

        vect_info = vmx->idt_vectoring_info;
        intr_info = vmx_get_intr_info(vcpu);

        if (is_machine_check(intr_info) || is_nmi(intr_info))
                return 1; /* handled by handle_exception_nmi_irqoff() */

        if (is_invalid_opcode(intr_info))
                return handle_ud(vcpu);

        error_code = 0;
        if (intr_info & INTR_INFO_DELIVER_CODE_MASK)
                error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);

        if (!vmx->rmode.vm86_active && is_gp_fault(intr_info)) {
                WARN_ON_ONCE(!enable_vmware_backdoor);

                /*
                 * VMware backdoor emulation on #GP interception only handles
                 * IN{S}, OUT{S}, and RDPMC, none of which generate a non-zero
                 * error code on #GP.
                 */
                if (error_code) {
                        kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
                        return 1;
                }
                return kvm_emulate_instruction(vcpu, EMULTYPE_VMWARE_GP);
        }

        /*
         * The #PF with PFEC.RSVD = 1 indicates the guest is accessing
         * MMIO, it is better to report an internal error.
         * See the comments in vmx_handle_exit.
         */
        if ((vect_info & VECTORING_INFO_VALID_MASK) &&
            !(is_page_fault(intr_info) && !(error_code & PFERR_RSVD_MASK))) {
                vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
                vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_SIMUL_EX;
                vcpu->run->internal.ndata = 4;
                vcpu->run->internal.data[0] = vect_info;
                vcpu->run->internal.data[1] = intr_info;
                vcpu->run->internal.data[2] = error_code;
                vcpu->run->internal.data[3] = vcpu->arch.last_vmentry_cpu;
                return 0;
        }

        if (is_page_fault(intr_info)) {
                cr2 = vmx_get_exit_qual(vcpu);
                if (enable_ept && !vcpu->arch.apf.host_apf_flags) {
                        /*
                         * EPT will cause page fault only if we need to
                         * detect illegal GPAs.
                         */
                        kvm_fixup_and_inject_pf_error(vcpu, cr2, error_code);
                        return 1;
                } else
                        return kvm_handle_page_fault(vcpu, error_code, cr2, NULL, 0);
        }

        ex_no = intr_info & INTR_INFO_VECTOR_MASK;

        if (vmx->rmode.vm86_active && rmode_exception(vcpu, ex_no))
                return handle_rmode_exception(vcpu, ex_no, error_code);

        switch (ex_no) {
        case DB_VECTOR:
                dr6 = vmx_get_exit_qual(vcpu);
                if (!(vcpu->guest_debug &
                      (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))) {
                        if (is_icebp(intr_info))
                                WARN_ON(!skip_emulated_instruction(vcpu));

                        kvm_queue_exception_p(vcpu, DB_VECTOR, dr6);
                        return 1;
                }
                kvm_run->debug.arch.dr6 = dr6 | DR6_FIXED_1 | DR6_RTM;
                kvm_run->debug.arch.dr7 = vmcs_readl(GUEST_DR7);
                fallthrough;
        case BP_VECTOR:
                /*
                 * Update instruction length as we may reinject #BP from
                 * user space while in guest debugging mode. Reading it for
                 * #DB as well causes no harm, it is not used in that case.
                 */
                vmx->vcpu.arch.event_exit_inst_len =
                        vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
                kvm_run->exit_reason = KVM_EXIT_DEBUG;
                rip = kvm_rip_read(vcpu);
                kvm_run->debug.arch.pc = vmcs_readl(GUEST_CS_BASE) + rip;
                kvm_run->debug.arch.exception = ex_no;
                break;
        case AC_VECTOR:
                if (guest_inject_ac(vcpu)) {
                        kvm_queue_exception_e(vcpu, AC_VECTOR, error_code);
                        return 1;
                }

                /*
                 * Handle split lock. Depending on detection mode this will
                 * either warn and disable split lock detection for this
                 * task or force SIGBUS on it.
                 */
                if (handle_guest_split_lock(kvm_rip_read(vcpu)))
                        return 1;
                fallthrough;
        default:
                kvm_run->exit_reason = KVM_EXIT_EXCEPTION;
                kvm_run->ex.exception = ex_no;
                kvm_run->ex.error_code = error_code;
                break;
        }
        return 0;
}

static __always_inline int handle_external_interrupt(struct kvm_vcpu *vcpu)
{
        ++vcpu->stat.irq_exits;
        return 1;
}

static int handle_triple_fault(struct kvm_vcpu *vcpu)
{
        vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN;
        vcpu->mmio_needed = 0;
        return 0;
}

static int handle_io(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification;
        int size, in, string;
        unsigned port;

        exit_qualification = vmx_get_exit_qual(vcpu);
        string = (exit_qualification & 16) != 0;

        ++vcpu->stat.io_exits;

        if (string)
                return kvm_emulate_instruction(vcpu, 0);

        port = exit_qualification >> 16;
        size = (exit_qualification & 7) + 1;
        in = (exit_qualification & 8) != 0;

        return kvm_fast_pio(vcpu, size, port, in);
}

static void
vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
{
        /*
         * Patch in the VMCALL instruction:
         */
        hypercall[0] = 0x0f;
        hypercall[1] = 0x01;
        hypercall[2] = 0xc1;
}

/* called to set cr0 as appropriate for a mov-to-cr0 exit. */
static int handle_set_cr0(struct kvm_vcpu *vcpu, unsigned long val)
{
        if (is_guest_mode(vcpu)) {
                struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
                unsigned long orig_val = val;

                /*
                 * We get here when L2 changed cr0 in a way that did not change
                 * any of L1's shadowed bits (see nested_vmx_exit_handled_cr),
                 * but did change L0 shadowed bits. So we first calculate the
                 * effective cr0 value that L1 would like to write into the
                 * hardware. It consists of the L2-owned bits from the new
                 * value combined with the L1-owned bits from L1's guest_cr0.
                 */
                val = (val & ~vmcs12->cr0_guest_host_mask) |
                        (vmcs12->guest_cr0 & vmcs12->cr0_guest_host_mask);

                if (!nested_guest_cr0_valid(vcpu, val))
                        return 1;

                if (kvm_set_cr0(vcpu, val))
                        return 1;
                vmcs_writel(CR0_READ_SHADOW, orig_val);
                return 0;
        } else {
                if (to_vmx(vcpu)->nested.vmxon &&
                    !nested_host_cr0_valid(vcpu, val))
                        return 1;

                return kvm_set_cr0(vcpu, val);
        }
}

static int handle_set_cr4(struct kvm_vcpu *vcpu, unsigned long val)
{
        if (is_guest_mode(vcpu)) {
                struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
                unsigned long orig_val = val;

                /* analogously to handle_set_cr0 */
                val = (val & ~vmcs12->cr4_guest_host_mask) |
                        (vmcs12->guest_cr4 & vmcs12->cr4_guest_host_mask);
                if (kvm_set_cr4(vcpu, val))
                        return 1;
                vmcs_writel(CR4_READ_SHADOW, orig_val);
                return 0;
        } else
                return kvm_set_cr4(vcpu, val);
}

static int handle_desc(struct kvm_vcpu *vcpu)
{
        WARN_ON(!(vcpu->arch.cr4 & X86_CR4_UMIP));
        return kvm_emulate_instruction(vcpu, 0);
}

static int handle_cr(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification, val;
        int cr;
        int reg;
        int err;
        int ret;

        exit_qualification = vmx_get_exit_qual(vcpu);
        cr = exit_qualification & 15;
        reg = (exit_qualification >> 8) & 15;
        switch ((exit_qualification >> 4) & 3) {
        case 0: /* mov to cr */
                val = kvm_register_readl(vcpu, reg);
                trace_kvm_cr_write(cr, val);
                switch (cr) {
                case 0:
                        err = handle_set_cr0(vcpu, val);
                        return kvm_complete_insn_gp(vcpu, err);
                case 3:
                        WARN_ON_ONCE(enable_unrestricted_guest);
                        err = kvm_set_cr3(vcpu, val);
                        return kvm_complete_insn_gp(vcpu, err);
                case 4:
                        err = handle_set_cr4(vcpu, val);
                        return kvm_complete_insn_gp(vcpu, err);
                case 8: {
                                u8 cr8_prev = kvm_get_cr8(vcpu);
                                u8 cr8 = (u8)val;
                                err = kvm_set_cr8(vcpu, cr8);
                                ret = kvm_complete_insn_gp(vcpu, err);
                                if (lapic_in_kernel(vcpu))
                                        return ret;
                                if (cr8_prev <= cr8)
                                        return ret;
                                /*
                                 * TODO: we might be squashing a
                                 * KVM_GUESTDBG_SINGLESTEP-triggered
                                 * KVM_EXIT_DEBUG here.
                                 */
                                vcpu->run->exit_reason = KVM_EXIT_SET_TPR;
                                return 0;
                        }
                }
                break;
        case 2: /* clts */
                WARN_ONCE(1, "Guest should always own CR0.TS");
                vmx_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
                trace_kvm_cr_write(0, kvm_read_cr0(vcpu));
                return kvm_skip_emulated_instruction(vcpu);
        case 1: /*mov from cr*/
                switch (cr) {
                case 3:
                        WARN_ON_ONCE(enable_unrestricted_guest);
                        val = kvm_read_cr3(vcpu);
                        kvm_register_write(vcpu, reg, val);
                        trace_kvm_cr_read(cr, val);
                        return kvm_skip_emulated_instruction(vcpu);
                case 8:
                        val = kvm_get_cr8(vcpu);
                        kvm_register_write(vcpu, reg, val);
                        trace_kvm_cr_read(cr, val);
                        return kvm_skip_emulated_instruction(vcpu);
                }
                break;
        case 3: /* lmsw */
                val = (exit_qualification >> LMSW_SOURCE_DATA_SHIFT) & 0x0f;
                trace_kvm_cr_write(0, (kvm_read_cr0(vcpu) & ~0xful) | val);
                kvm_lmsw(vcpu, val);

                return kvm_skip_emulated_instruction(vcpu);
        default:
                break;
        }
        vcpu->run->exit_reason = 0;
        vcpu_unimpl(vcpu, "unhandled control register: op %d cr %d\n",
               (int)(exit_qualification >> 4) & 3, cr);
        return 0;
}

static int handle_dr(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification;
        int dr, dr7, reg;

        exit_qualification = vmx_get_exit_qual(vcpu);
        dr = exit_qualification & DEBUG_REG_ACCESS_NUM;

        /* First, if DR does not exist, trigger UD */
        if (!kvm_require_dr(vcpu, dr))
                return 1;

        /* Do not handle if the CPL > 0, will trigger GP on re-entry */
        if (!kvm_require_cpl(vcpu, 0))
                return 1;
        dr7 = vmcs_readl(GUEST_DR7);
        if (dr7 & DR7_GD) {
                /*
                 * As the vm-exit takes precedence over the debug trap, we
                 * need to emulate the latter, either for the host or the
                 * guest debugging itself.
                 */
                if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) {
                        vcpu->run->debug.arch.dr6 = DR6_BD | DR6_RTM | DR6_FIXED_1;
                        vcpu->run->debug.arch.dr7 = dr7;
                        vcpu->run->debug.arch.pc = kvm_get_linear_rip(vcpu);
                        vcpu->run->debug.arch.exception = DB_VECTOR;
                        vcpu->run->exit_reason = KVM_EXIT_DEBUG;
                        return 0;
                } else {
                        kvm_queue_exception_p(vcpu, DB_VECTOR, DR6_BD);
                        return 1;
                }
        }

        if (vcpu->guest_debug == 0) {
                exec_controls_clearbit(to_vmx(vcpu), CPU_BASED_MOV_DR_EXITING);

                /*
                 * No more DR vmexits; force a reload of the debug registers
                 * and reenter on this instruction.  The next vmexit will
                 * retrieve the full state of the debug registers.
                 */
                vcpu->arch.switch_db_regs |= KVM_DEBUGREG_WONT_EXIT;
                return 1;
        }

        reg = DEBUG_REG_ACCESS_REG(exit_qualification);
        if (exit_qualification & TYPE_MOV_FROM_DR) {
                unsigned long val;

                if (kvm_get_dr(vcpu, dr, &val))
                        return 1;
                kvm_register_write(vcpu, reg, val);
        } else
                if (kvm_set_dr(vcpu, dr, kvm_register_readl(vcpu, reg)))
                        return 1;

        return kvm_skip_emulated_instruction(vcpu);
}

static void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu)
{
        get_debugreg(vcpu->arch.db[0], 0);
        get_debugreg(vcpu->arch.db[1], 1);
        get_debugreg(vcpu->arch.db[2], 2);
        get_debugreg(vcpu->arch.db[3], 3);
        get_debugreg(vcpu->arch.dr6, 6);
        vcpu->arch.dr7 = vmcs_readl(GUEST_DR7);

        vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_WONT_EXIT;
        exec_controls_setbit(to_vmx(vcpu), CPU_BASED_MOV_DR_EXITING);
}

static void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val)
{
        vmcs_writel(GUEST_DR7, val);
}

static int handle_tpr_below_threshold(struct kvm_vcpu *vcpu)
{
        kvm_apic_update_ppr(vcpu);
        return 1;
}

static int handle_interrupt_window(struct kvm_vcpu *vcpu)
{
        exec_controls_clearbit(to_vmx(vcpu), CPU_BASED_INTR_WINDOW_EXITING);

        kvm_make_request(KVM_REQ_EVENT, vcpu);

        ++vcpu->stat.irq_window_exits;
        return 1;
}

static int handle_vmcall(struct kvm_vcpu *vcpu)
{
        return kvm_emulate_hypercall(vcpu);
}

static int handle_invd(struct kvm_vcpu *vcpu)
{
        /* Treat an INVD instruction as a NOP and just skip it. */
        return kvm_skip_emulated_instruction(vcpu);
}

static int handle_invlpg(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification = vmx_get_exit_qual(vcpu);

        kvm_mmu_invlpg(vcpu, exit_qualification);
        return kvm_skip_emulated_instruction(vcpu);
}

static int handle_rdpmc(struct kvm_vcpu *vcpu)
{
        int err;

        err = kvm_rdpmc(vcpu);
        return kvm_complete_insn_gp(vcpu, err);
}

static int handle_wbinvd(struct kvm_vcpu *vcpu)
{
        return kvm_emulate_wbinvd(vcpu);
}

static int handle_xsetbv(struct kvm_vcpu *vcpu)
{
        u64 new_bv = kvm_read_edx_eax(vcpu);
        u32 index = kvm_rcx_read(vcpu);

        if (kvm_set_xcr(vcpu, index, new_bv) == 0)
                return kvm_skip_emulated_instruction(vcpu);
        return 1;
}

static int handle_apic_access(struct kvm_vcpu *vcpu)
{
        if (likely(fasteoi)) {
                unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
                int access_type, offset;

                access_type = exit_qualification & APIC_ACCESS_TYPE;
                offset = exit_qualification & APIC_ACCESS_OFFSET;
                /*
                 * Sane guest uses MOV to write EOI, with written value
                 * not cared. So make a short-circuit here by avoiding
                 * heavy instruction emulation.
                 */
                if ((access_type == TYPE_LINEAR_APIC_INST_WRITE) &&
                    (offset == APIC_EOI)) {
                        kvm_lapic_set_eoi(vcpu);
                        return kvm_skip_emulated_instruction(vcpu);
                }
        }
        return kvm_emulate_instruction(vcpu, 0);
}

static int handle_apic_eoi_induced(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
        int vector = exit_qualification & 0xff;

        /* EOI-induced VM exit is trap-like and thus no need to adjust IP */
        kvm_apic_set_eoi_accelerated(vcpu, vector);
        return 1;
}

static int handle_apic_write(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
        u32 offset = exit_qualification & 0xfff;

        /* APIC-write VM exit is trap-like and thus no need to adjust IP */
        kvm_apic_write_nodecode(vcpu, offset);
        return 1;
}

static int handle_task_switch(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long exit_qualification;
        bool has_error_code = false;
        u32 error_code = 0;
        u16 tss_selector;
        int reason, type, idt_v, idt_index;

        idt_v = (vmx->idt_vectoring_info & VECTORING_INFO_VALID_MASK);
        idt_index = (vmx->idt_vectoring_info & VECTORING_INFO_VECTOR_MASK);
        type = (vmx->idt_vectoring_info & VECTORING_INFO_TYPE_MASK);

        exit_qualification = vmx_get_exit_qual(vcpu);

        reason = (u32)exit_qualification >> 30;
        if (reason == TASK_SWITCH_GATE && idt_v) {
                switch (type) {
                case INTR_TYPE_NMI_INTR:
                        vcpu->arch.nmi_injected = false;
                        vmx_set_nmi_mask(vcpu, true);
                        break;
                case INTR_TYPE_EXT_INTR:
                case INTR_TYPE_SOFT_INTR:
                        kvm_clear_interrupt_queue(vcpu);
                        break;
                case INTR_TYPE_HARD_EXCEPTION:
                        if (vmx->idt_vectoring_info &
                            VECTORING_INFO_DELIVER_CODE_MASK) {
                                has_error_code = true;
                                error_code =
                                        vmcs_read32(IDT_VECTORING_ERROR_CODE);
                        }
                        fallthrough;
                case INTR_TYPE_SOFT_EXCEPTION:
                        kvm_clear_exception_queue(vcpu);
                        break;
                default:
                        break;
                }
        }
        tss_selector = exit_qualification;

        if (!idt_v || (type != INTR_TYPE_HARD_EXCEPTION &&
                       type != INTR_TYPE_EXT_INTR &&
                       type != INTR_TYPE_NMI_INTR))
                WARN_ON(!skip_emulated_instruction(vcpu));

        /*
         * TODO: What about debug traps on tss switch?
         *       Are we supposed to inject them and update dr6?
         */
        return kvm_task_switch(vcpu, tss_selector,
                               type == INTR_TYPE_SOFT_INTR ? idt_index : -1,
                               reason, has_error_code, error_code);
}

static int handle_ept_violation(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification;
        gpa_t gpa;
        u64 error_code;

        exit_qualification = vmx_get_exit_qual(vcpu);

        /*
         * EPT violation happened while executing iret from NMI,
         * "blocked by NMI" bit has to be set before next VM entry.
         * There are errata that may cause this bit to not be set:
         * AAK134, BY25.
         */
        if (!(to_vmx(vcpu)->idt_vectoring_info & VECTORING_INFO_VALID_MASK) &&
                        enable_vnmi &&
                        (exit_qualification & INTR_INFO_UNBLOCK_NMI))
                vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO, GUEST_INTR_STATE_NMI);

        gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
        trace_kvm_page_fault(gpa, exit_qualification);

        /* Is it a read fault? */
        error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
                     ? PFERR_USER_MASK : 0;
        /* Is it a write fault? */
        error_code |= (exit_qualification & EPT_VIOLATION_ACC_WRITE)
                      ? PFERR_WRITE_MASK : 0;
        /* Is it a fetch fault? */
        error_code |= (exit_qualification & EPT_VIOLATION_ACC_INSTR)
                      ? PFERR_FETCH_MASK : 0;
        /* ept page table entry is present? */
        error_code |= (exit_qualification &
                       (EPT_VIOLATION_READABLE | EPT_VIOLATION_WRITABLE |
                        EPT_VIOLATION_EXECUTABLE))
                      ? PFERR_PRESENT_MASK : 0;

        error_code |= (exit_qualification & 0x100) != 0 ?
               PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;

        vcpu->arch.exit_qualification = exit_qualification;

        /*
         * Check that the GPA doesn't exceed physical memory limits, as that is
         * a guest page fault.  We have to emulate the instruction here, because
         * if the illegal address is that of a paging structure, then
         * EPT_VIOLATION_ACC_WRITE bit is set.  Alternatively, if supported we
         * would also use advanced VM-exit information for EPT violations to
         * reconstruct the page fault error code.
         */
        if (unlikely(kvm_vcpu_is_illegal_gpa(vcpu, gpa)))
                return kvm_emulate_instruction(vcpu, 0);

        return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
}

static int handle_ept_misconfig(struct kvm_vcpu *vcpu)
{
        gpa_t gpa;

        /*
         * A nested guest cannot optimize MMIO vmexits, because we have an
         * nGPA here instead of the required GPA.
         */
        gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
        if (!is_guest_mode(vcpu) &&
            !kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, gpa, 0, NULL)) {
                trace_kvm_fast_mmio(gpa);
                return kvm_skip_emulated_instruction(vcpu);
        }

        return kvm_mmu_page_fault(vcpu, gpa, PFERR_RSVD_MASK, NULL, 0);
}

static int handle_nmi_window(struct kvm_vcpu *vcpu)
{
        WARN_ON_ONCE(!enable_vnmi);
        exec_controls_clearbit(to_vmx(vcpu), CPU_BASED_NMI_WINDOW_EXITING);
        ++vcpu->stat.nmi_window_exits;
        kvm_make_request(KVM_REQ_EVENT, vcpu);

        return 1;
}

static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        bool intr_window_requested;
        unsigned count = 130;

        intr_window_requested = exec_controls_get(vmx) &
                                CPU_BASED_INTR_WINDOW_EXITING;

        while (vmx->emulation_required && count-- != 0) {
                if (intr_window_requested && !vmx_interrupt_blocked(vcpu))
                        return handle_interrupt_window(&vmx->vcpu);

                if (kvm_test_request(KVM_REQ_EVENT, vcpu))
                        return 1;

                if (!kvm_emulate_instruction(vcpu, 0))
                        return 0;

                if (vmx->emulation_required && !vmx->rmode.vm86_active &&
                    vcpu->arch.exception.pending) {
                        vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
                        vcpu->run->internal.suberror =
                                                KVM_INTERNAL_ERROR_EMULATION;
                        vcpu->run->internal.ndata = 0;
                        return 0;
                }

                if (vcpu->arch.halt_request) {
                        vcpu->arch.halt_request = 0;
                        return kvm_vcpu_halt(vcpu);
                }

                /*
                 * Note, return 1 and not 0, vcpu_run() will invoke
                 * xfer_to_guest_mode() which will create a proper return
                 * code.
                 */
                if (__xfer_to_guest_mode_work_pending())
                        return 1;
        }

        return 1;
}

static void grow_ple_window(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned int old = vmx->ple_window;

        vmx->ple_window = __grow_ple_window(old, ple_window,
                                            ple_window_grow,
                                            ple_window_max);

        if (vmx->ple_window != old) {
                vmx->ple_window_dirty = true;
                trace_kvm_ple_window_update(vcpu->vcpu_id,
                                            vmx->ple_window, old);
        }
}

static void shrink_ple_window(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned int old = vmx->ple_window;

        vmx->ple_window = __shrink_ple_window(old, ple_window,
                                              ple_window_shrink,
                                              ple_window);

        if (vmx->ple_window != old) {
                vmx->ple_window_dirty = true;
                trace_kvm_ple_window_update(vcpu->vcpu_id,
                                            vmx->ple_window, old);
        }
}

static void vmx_enable_tdp(void)
{
        kvm_mmu_set_mask_ptes(VMX_EPT_READABLE_MASK,
                enable_ept_ad_bits ? VMX_EPT_ACCESS_BIT : 0ull,
                enable_ept_ad_bits ? VMX_EPT_DIRTY_BIT : 0ull,
                0ull, VMX_EPT_EXECUTABLE_MASK,
                cpu_has_vmx_ept_execute_only() ? 0ull : VMX_EPT_READABLE_MASK,
                VMX_EPT_RWX_MASK, 0ull);

        ept_set_mmio_spte_mask();
}

/*
 * Indicate a busy-waiting vcpu in spinlock. We do not enable the PAUSE
 * exiting, so only get here on cpu with PAUSE-Loop-Exiting.
 */
static int handle_pause(struct kvm_vcpu *vcpu)
{
        if (!kvm_pause_in_guest(vcpu->kvm))
                grow_ple_window(vcpu);

        /*
         * Intel sdm vol3 ch-25.1.3 says: The "PAUSE-loop exiting"
         * VM-execution control is ignored if CPL > 0. OTOH, KVM
         * never set PAUSE_EXITING and just set PLE if supported,
         * so the vcpu must be CPL=0 if it gets a PAUSE exit.
         */
        kvm_vcpu_on_spin(vcpu, true);
        return kvm_skip_emulated_instruction(vcpu);
}

static int handle_nop(struct kvm_vcpu *vcpu)
{
        return kvm_skip_emulated_instruction(vcpu);
}

static int handle_mwait(struct kvm_vcpu *vcpu)
{
        printk_once(KERN_WARNING "kvm: MWAIT instruction emulated as NOP!\n");
        return handle_nop(vcpu);
}

static int handle_invalid_op(struct kvm_vcpu *vcpu)
{
        kvm_queue_exception(vcpu, UD_VECTOR);
        return 1;
}

static int handle_monitor_trap(struct kvm_vcpu *vcpu)
{
        return 1;
}

static int handle_monitor(struct kvm_vcpu *vcpu)
{
        printk_once(KERN_WARNING "kvm: MONITOR instruction emulated as NOP!\n");
        return handle_nop(vcpu);
}

static int handle_invpcid(struct kvm_vcpu *vcpu)
{
        u32 vmx_instruction_info;
        unsigned long type;
        gva_t gva;
        struct {
                u64 pcid;
                u64 gla;
        } operand;

        if (!guest_cpuid_has(vcpu, X86_FEATURE_INVPCID)) {
                kvm_queue_exception(vcpu, UD_VECTOR);
                return 1;
        }

        vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
        type = kvm_register_readl(vcpu, (vmx_instruction_info >> 28) & 0xf);

        if (type > 3) {
                kvm_inject_gp(vcpu, 0);
                return 1;
        }

        /* According to the Intel instruction reference, the memory operand
         * is read even if it isn't needed (e.g., for type==all)
         */
        if (get_vmx_mem_address(vcpu, vmx_get_exit_qual(vcpu),
                                vmx_instruction_info, false,
                                sizeof(operand), &gva))
                return 1;

        return kvm_handle_invpcid(vcpu, type, gva);
}

static int handle_pml_full(struct kvm_vcpu *vcpu)
{
        unsigned long exit_qualification;

        trace_kvm_pml_full(vcpu->vcpu_id);

        exit_qualification = vmx_get_exit_qual(vcpu);

        /*
         * PML buffer FULL happened while executing iret from NMI,
         * "blocked by NMI" bit has to be set before next VM entry.
         */
        if (!(to_vmx(vcpu)->idt_vectoring_info & VECTORING_INFO_VALID_MASK) &&
                        enable_vnmi &&
                        (exit_qualification & INTR_INFO_UNBLOCK_NMI))
                vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
                                GUEST_INTR_STATE_NMI);

        /*
         * PML buffer already flushed at beginning of VMEXIT. Nothing to do
         * here.., and there's no userspace involvement needed for PML.
         */
        return 1;
}

static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (!vmx->req_immediate_exit &&
            !unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) {
                kvm_lapic_expired_hv_timer(vcpu);
                return EXIT_FASTPATH_REENTER_GUEST;
        }

        return EXIT_FASTPATH_NONE;
}

static int handle_preemption_timer(struct kvm_vcpu *vcpu)
{
        handle_fastpath_preemption_timer(vcpu);
        return 1;
}

/*
 * When nested=0, all VMX instruction VM Exits filter here.  The handlers
 * are overwritten by nested_vmx_setup() when nested=1.
 */
static int handle_vmx_instruction(struct kvm_vcpu *vcpu)
{
        kvm_queue_exception(vcpu, UD_VECTOR);
        return 1;
}

static int handle_encls(struct kvm_vcpu *vcpu)
{
        /*
         * SGX virtualization is not yet supported.  There is no software
         * enable bit for SGX, so we have to trap ENCLS and inject a #UD
         * to prevent the guest from executing ENCLS.
         */
        kvm_queue_exception(vcpu, UD_VECTOR);
        return 1;
}

/*
 * The exit handlers return 1 if the exit was handled fully and guest execution
 * may resume.  Otherwise they set the kvm_run parameter to indicate what needs
 * to be done to userspace and return 0.
 */
static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
        [EXIT_REASON_EXCEPTION_NMI]           = handle_exception_nmi,
        [EXIT_REASON_EXTERNAL_INTERRUPT]      = handle_external_interrupt,
        [EXIT_REASON_TRIPLE_FAULT]            = handle_triple_fault,
        [EXIT_REASON_NMI_WINDOW]              = handle_nmi_window,
        [EXIT_REASON_IO_INSTRUCTION]          = handle_io,
        [EXIT_REASON_CR_ACCESS]               = handle_cr,
        [EXIT_REASON_DR_ACCESS]               = handle_dr,
        [EXIT_REASON_CPUID]                   = kvm_emulate_cpuid,
        [EXIT_REASON_MSR_READ]                = kvm_emulate_rdmsr,
        [EXIT_REASON_MSR_WRITE]               = kvm_emulate_wrmsr,
        [EXIT_REASON_INTERRUPT_WINDOW]        = handle_interrupt_window,
        [EXIT_REASON_HLT]                     = kvm_emulate_halt,
        [EXIT_REASON_INVD]                    = handle_invd,
        [EXIT_REASON_INVLPG]                  = handle_invlpg,
        [EXIT_REASON_RDPMC]                   = handle_rdpmc,
        [EXIT_REASON_VMCALL]                  = handle_vmcall,
        [EXIT_REASON_VMCLEAR]                 = handle_vmx_instruction,
        [EXIT_REASON_VMLAUNCH]                = handle_vmx_instruction,
        [EXIT_REASON_VMPTRLD]                 = handle_vmx_instruction,
        [EXIT_REASON_VMPTRST]                 = handle_vmx_instruction,
        [EXIT_REASON_VMREAD]                  = handle_vmx_instruction,
        [EXIT_REASON_VMRESUME]                = handle_vmx_instruction,
        [EXIT_REASON_VMWRITE]                 = handle_vmx_instruction,
        [EXIT_REASON_VMOFF]                   = handle_vmx_instruction,
        [EXIT_REASON_VMON]                    = handle_vmx_instruction,
        [EXIT_REASON_TPR_BELOW_THRESHOLD]     = handle_tpr_below_threshold,
        [EXIT_REASON_APIC_ACCESS]             = handle_apic_access,
        [EXIT_REASON_APIC_WRITE]              = handle_apic_write,
        [EXIT_REASON_EOI_INDUCED]             = handle_apic_eoi_induced,
        [EXIT_REASON_WBINVD]                  = handle_wbinvd,
        [EXIT_REASON_XSETBV]                  = handle_xsetbv,
        [EXIT_REASON_TASK_SWITCH]             = handle_task_switch,
        [EXIT_REASON_MCE_DURING_VMENTRY]      = handle_machine_check,
        [EXIT_REASON_GDTR_IDTR]               = handle_desc,
        [EXIT_REASON_LDTR_TR]                 = handle_desc,
        [EXIT_REASON_EPT_VIOLATION]           = handle_ept_violation,
        [EXIT_REASON_EPT_MISCONFIG]           = handle_ept_misconfig,
        [EXIT_REASON_PAUSE_INSTRUCTION]       = handle_pause,
        [EXIT_REASON_MWAIT_INSTRUCTION]       = handle_mwait,
        [EXIT_REASON_MONITOR_TRAP_FLAG]       = handle_monitor_trap,
        [EXIT_REASON_MONITOR_INSTRUCTION]     = handle_monitor,
        [EXIT_REASON_INVEPT]                  = handle_vmx_instruction,
        [EXIT_REASON_INVVPID]                 = handle_vmx_instruction,
        [EXIT_REASON_RDRAND]                  = handle_invalid_op,
        [EXIT_REASON_RDSEED]                  = handle_invalid_op,
        [EXIT_REASON_PML_FULL]                = handle_pml_full,
        [EXIT_REASON_INVPCID]                 = handle_invpcid,
        [EXIT_REASON_VMFUNC]                  = handle_vmx_instruction,
        [EXIT_REASON_PREEMPTION_TIMER]        = handle_preemption_timer,
        [EXIT_REASON_ENCLS]                   = handle_encls,
};

static const int kvm_vmx_max_exit_handlers =
        ARRAY_SIZE(kvm_vmx_exit_handlers);

static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2,
                              u32 *intr_info, u32 *error_code)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        *info1 = vmx_get_exit_qual(vcpu);
        if (!(vmx->exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY)) {
                *info2 = vmx->idt_vectoring_info;
                *intr_info = vmx_get_intr_info(vcpu);
                if (is_exception_with_error_code(*intr_info))
                        *error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
                else
                        *error_code = 0;
        } else {
                *info2 = 0;
                *intr_info = 0;
                *error_code = 0;
        }
}

static void vmx_destroy_pml_buffer(struct vcpu_vmx *vmx)
{
        if (vmx->pml_pg) {
                __free_page(vmx->pml_pg);
                vmx->pml_pg = NULL;
        }
}

static void vmx_flush_pml_buffer(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        u64 *pml_buf;
        u16 pml_idx;

        pml_idx = vmcs_read16(GUEST_PML_INDEX);

        /* Do nothing if PML buffer is empty */
        if (pml_idx == (PML_ENTITY_NUM - 1))
                return;

        /* PML index always points to next available PML buffer entity */
        if (pml_idx >= PML_ENTITY_NUM)
                pml_idx = 0;
        else
                pml_idx++;

        pml_buf = page_address(vmx->pml_pg);
        for (; pml_idx < PML_ENTITY_NUM; pml_idx++) {
                u64 gpa;

                gpa = pml_buf[pml_idx];
                WARN_ON(gpa & (PAGE_SIZE - 1));
                kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT);
        }

        /* reset PML index */
        vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1);
}

/*
 * Flush all vcpus' PML buffer and update logged GPAs to dirty_bitmap.
 * Called before reporting dirty_bitmap to userspace.
 */
static void kvm_flush_pml_buffers(struct kvm *kvm)
{
        int i;
        struct kvm_vcpu *vcpu;
        /*
         * We only need to kick vcpu out of guest mode here, as PML buffer
         * is flushed at beginning of all VMEXITs, and it's obvious that only
         * vcpus running in guest are possible to have unflushed GPAs in PML
         * buffer.
         */
        kvm_for_each_vcpu(i, vcpu, kvm)
                kvm_vcpu_kick(vcpu);
}

static void vmx_dump_sel(char *name, uint32_t sel)
{
        pr_err("%s sel=0x%04x, attr=0x%05x, limit=0x%08x, base=0x%016lx\n",
               name, vmcs_read16(sel),
               vmcs_read32(sel + GUEST_ES_AR_BYTES - GUEST_ES_SELECTOR),
               vmcs_read32(sel + GUEST_ES_LIMIT - GUEST_ES_SELECTOR),
               vmcs_readl(sel + GUEST_ES_BASE - GUEST_ES_SELECTOR));
}

static void vmx_dump_dtsel(char *name, uint32_t limit)
{
        pr_err("%s                           limit=0x%08x, base=0x%016lx\n",
               name, vmcs_read32(limit),
               vmcs_readl(limit + GUEST_GDTR_BASE - GUEST_GDTR_LIMIT));
}

void dump_vmcs(void)
{
        u32 vmentry_ctl, vmexit_ctl;
        u32 cpu_based_exec_ctrl, pin_based_exec_ctrl, secondary_exec_control;
        unsigned long cr4;
        u64 efer;

        if (!dump_invalid_vmcs) {
                pr_warn_ratelimited("set kvm_intel.dump_invalid_vmcs=1 to dump internal KVM state.\n");
                return;
        }

        vmentry_ctl = vmcs_read32(VM_ENTRY_CONTROLS);
        vmexit_ctl = vmcs_read32(VM_EXIT_CONTROLS);
        cpu_based_exec_ctrl = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
        pin_based_exec_ctrl = vmcs_read32(PIN_BASED_VM_EXEC_CONTROL);
        cr4 = vmcs_readl(GUEST_CR4);
        efer = vmcs_read64(GUEST_IA32_EFER);
        secondary_exec_control = 0;
        if (cpu_has_secondary_exec_ctrls())
                secondary_exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL);

        pr_err("*** Guest State ***\n");
        pr_err("CR0: actual=0x%016lx, shadow=0x%016lx, gh_mask=%016lx\n",
               vmcs_readl(GUEST_CR0), vmcs_readl(CR0_READ_SHADOW),
               vmcs_readl(CR0_GUEST_HOST_MASK));
        pr_err("CR4: actual=0x%016lx, shadow=0x%016lx, gh_mask=%016lx\n",
               cr4, vmcs_readl(CR4_READ_SHADOW), vmcs_readl(CR4_GUEST_HOST_MASK));
        pr_err("CR3 = 0x%016lx\n", vmcs_readl(GUEST_CR3));
        if ((secondary_exec_control & SECONDARY_EXEC_ENABLE_EPT) &&
            (cr4 & X86_CR4_PAE) && !(efer & EFER_LMA))
        {
                pr_err("PDPTR0 = 0x%016llx  PDPTR1 = 0x%016llx\n",
                       vmcs_read64(GUEST_PDPTR0), vmcs_read64(GUEST_PDPTR1));
                pr_err("PDPTR2 = 0x%016llx  PDPTR3 = 0x%016llx\n",
                       vmcs_read64(GUEST_PDPTR2), vmcs_read64(GUEST_PDPTR3));
        }
        pr_err("RSP = 0x%016lx  RIP = 0x%016lx\n",
               vmcs_readl(GUEST_RSP), vmcs_readl(GUEST_RIP));
        pr_err("RFLAGS=0x%08lx         DR7 = 0x%016lx\n",
               vmcs_readl(GUEST_RFLAGS), vmcs_readl(GUEST_DR7));
        pr_err("Sysenter RSP=%016lx CS:RIP=%04x:%016lx\n",
               vmcs_readl(GUEST_SYSENTER_ESP),
               vmcs_read32(GUEST_SYSENTER_CS), vmcs_readl(GUEST_SYSENTER_EIP));
        vmx_dump_sel("CS:  ", GUEST_CS_SELECTOR);
        vmx_dump_sel("DS:  ", GUEST_DS_SELECTOR);
        vmx_dump_sel("SS:  ", GUEST_SS_SELECTOR);
        vmx_dump_sel("ES:  ", GUEST_ES_SELECTOR);
        vmx_dump_sel("FS:  ", GUEST_FS_SELECTOR);
        vmx_dump_sel("GS:  ", GUEST_GS_SELECTOR);
        vmx_dump_dtsel("GDTR:", GUEST_GDTR_LIMIT);
        vmx_dump_sel("LDTR:", GUEST_LDTR_SELECTOR);
        vmx_dump_dtsel("IDTR:", GUEST_IDTR_LIMIT);
        vmx_dump_sel("TR:  ", GUEST_TR_SELECTOR);
        if ((vmexit_ctl & (VM_EXIT_SAVE_IA32_PAT | VM_EXIT_SAVE_IA32_EFER)) ||
            (vmentry_ctl & (VM_ENTRY_LOAD_IA32_PAT | VM_ENTRY_LOAD_IA32_EFER)))
                pr_err("EFER =     0x%016llx  PAT = 0x%016llx\n",
                       efer, vmcs_read64(GUEST_IA32_PAT));
        pr_err("DebugCtl = 0x%016llx  DebugExceptions = 0x%016lx\n",
               vmcs_read64(GUEST_IA32_DEBUGCTL),
               vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS));
        if (cpu_has_load_perf_global_ctrl() &&
            vmentry_ctl & VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL)
                pr_err("PerfGlobCtl = 0x%016llx\n",
                       vmcs_read64(GUEST_IA32_PERF_GLOBAL_CTRL));
        if (vmentry_ctl & VM_ENTRY_LOAD_BNDCFGS)
                pr_err("BndCfgS = 0x%016llx\n", vmcs_read64(GUEST_BNDCFGS));
        pr_err("Interruptibility = %08x  ActivityState = %08x\n",
               vmcs_read32(GUEST_INTERRUPTIBILITY_INFO),
               vmcs_read32(GUEST_ACTIVITY_STATE));
        if (secondary_exec_control & SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY)
                pr_err("InterruptStatus = %04x\n",
                       vmcs_read16(GUEST_INTR_STATUS));

        pr_err("*** Host State ***\n");
        pr_err("RIP = 0x%016lx  RSP = 0x%016lx\n",
               vmcs_readl(HOST_RIP), vmcs_readl(HOST_RSP));
        pr_err("CS=%04x SS=%04x DS=%04x ES=%04x FS=%04x GS=%04x TR=%04x\n",
               vmcs_read16(HOST_CS_SELECTOR), vmcs_read16(HOST_SS_SELECTOR),
               vmcs_read16(HOST_DS_SELECTOR), vmcs_read16(HOST_ES_SELECTOR),
               vmcs_read16(HOST_FS_SELECTOR), vmcs_read16(HOST_GS_SELECTOR),
               vmcs_read16(HOST_TR_SELECTOR));
        pr_err("FSBase=%016lx GSBase=%016lx TRBase=%016lx\n",
               vmcs_readl(HOST_FS_BASE), vmcs_readl(HOST_GS_BASE),
               vmcs_readl(HOST_TR_BASE));
        pr_err("GDTBase=%016lx IDTBase=%016lx\n",
               vmcs_readl(HOST_GDTR_BASE), vmcs_readl(HOST_IDTR_BASE));
        pr_err("CR0=%016lx CR3=%016lx CR4=%016lx\n",
               vmcs_readl(HOST_CR0), vmcs_readl(HOST_CR3),
               vmcs_readl(HOST_CR4));
        pr_err("Sysenter RSP=%016lx CS:RIP=%04x:%016lx\n",
               vmcs_readl(HOST_IA32_SYSENTER_ESP),
               vmcs_read32(HOST_IA32_SYSENTER_CS),
               vmcs_readl(HOST_IA32_SYSENTER_EIP));
        if (vmexit_ctl & (VM_EXIT_LOAD_IA32_PAT | VM_EXIT_LOAD_IA32_EFER))
                pr_err("EFER = 0x%016llx  PAT = 0x%016llx\n",
                       vmcs_read64(HOST_IA32_EFER),
                       vmcs_read64(HOST_IA32_PAT));
        if (cpu_has_load_perf_global_ctrl() &&
            vmexit_ctl & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL)
                pr_err("PerfGlobCtl = 0x%016llx\n",
                       vmcs_read64(HOST_IA32_PERF_GLOBAL_CTRL));

        pr_err("*** Control State ***\n");
        pr_err("PinBased=%08x CPUBased=%08x SecondaryExec=%08x\n",
               pin_based_exec_ctrl, cpu_based_exec_ctrl, secondary_exec_control);
        pr_err("EntryControls=%08x ExitControls=%08x\n", vmentry_ctl, vmexit_ctl);
        pr_err("ExceptionBitmap=%08x PFECmask=%08x PFECmatch=%08x\n",
               vmcs_read32(EXCEPTION_BITMAP),
               vmcs_read32(PAGE_FAULT_ERROR_CODE_MASK),
               vmcs_read32(PAGE_FAULT_ERROR_CODE_MATCH));
        pr_err("VMEntry: intr_info=%08x errcode=%08x ilen=%08x\n",
               vmcs_read32(VM_ENTRY_INTR_INFO_FIELD),
               vmcs_read32(VM_ENTRY_EXCEPTION_ERROR_CODE),
               vmcs_read32(VM_ENTRY_INSTRUCTION_LEN));
        pr_err("VMExit: intr_info=%08x errcode=%08x ilen=%08x\n",
               vmcs_read32(VM_EXIT_INTR_INFO),
               vmcs_read32(VM_EXIT_INTR_ERROR_CODE),
               vmcs_read32(VM_EXIT_INSTRUCTION_LEN));
        pr_err("        reason=%08x qualification=%016lx\n",
               vmcs_read32(VM_EXIT_REASON), vmcs_readl(EXIT_QUALIFICATION));
        pr_err("IDTVectoring: info=%08x errcode=%08x\n",
               vmcs_read32(IDT_VECTORING_INFO_FIELD),
               vmcs_read32(IDT_VECTORING_ERROR_CODE));
        pr_err("TSC Offset = 0x%016llx\n", vmcs_read64(TSC_OFFSET));
        if (secondary_exec_control & SECONDARY_EXEC_TSC_SCALING)
                pr_err("TSC Multiplier = 0x%016llx\n",
                       vmcs_read64(TSC_MULTIPLIER));
        if (cpu_based_exec_ctrl & CPU_BASED_TPR_SHADOW) {
                if (secondary_exec_control & SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY) {
                        u16 status = vmcs_read16(GUEST_INTR_STATUS);
                        pr_err("SVI|RVI = %02x|%02x ", status >> 8, status & 0xff);
                }
                pr_cont("TPR Threshold = 0x%02x\n", vmcs_read32(TPR_THRESHOLD));
                if (secondary_exec_control & SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)
                        pr_err("APIC-access addr = 0x%016llx ", vmcs_read64(APIC_ACCESS_ADDR));
                pr_cont("virt-APIC addr = 0x%016llx\n", vmcs_read64(VIRTUAL_APIC_PAGE_ADDR));
        }
        if (pin_based_exec_ctrl & PIN_BASED_POSTED_INTR)
                pr_err("PostedIntrVec = 0x%02x\n", vmcs_read16(POSTED_INTR_NV));
        if ((secondary_exec_control & SECONDARY_EXEC_ENABLE_EPT))
                pr_err("EPT pointer = 0x%016llx\n", vmcs_read64(EPT_POINTER));
        if (secondary_exec_control & SECONDARY_EXEC_PAUSE_LOOP_EXITING)
                pr_err("PLE Gap=%08x Window=%08x\n",
                       vmcs_read32(PLE_GAP), vmcs_read32(PLE_WINDOW));
        if (secondary_exec_control & SECONDARY_EXEC_ENABLE_VPID)
                pr_err("Virtual processor ID = 0x%04x\n",
                       vmcs_read16(VIRTUAL_PROCESSOR_ID));
}

/*
 * The guest has exited.  See if we can fix it or if we need userspace
 * assistance.
 */
static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        u32 exit_reason = vmx->exit_reason;
        u32 vectoring_info = vmx->idt_vectoring_info;

        /*
         * Flush logged GPAs PML buffer, this will make dirty_bitmap more
         * updated. Another good is, in kvm_vm_ioctl_get_dirty_log, before
         * querying dirty_bitmap, we only need to kick all vcpus out of guest
         * mode as if vcpus is in root mode, the PML buffer must has been
         * flushed already.
         */
        if (enable_pml)
                vmx_flush_pml_buffer(vcpu);

        /*
         * We should never reach this point with a pending nested VM-Enter, and
         * more specifically emulation of L2 due to invalid guest state (see
         * below) should never happen as that means we incorrectly allowed a
         * nested VM-Enter with an invalid vmcs12.
         */
        WARN_ON_ONCE(vmx->nested.nested_run_pending);

        /* If guest state is invalid, start emulating */
        if (vmx->emulation_required)
                return handle_invalid_guest_state(vcpu);

        if (is_guest_mode(vcpu)) {
                /*
                 * The host physical addresses of some pages of guest memory
                 * are loaded into the vmcs02 (e.g. vmcs12's Virtual APIC
                 * Page). The CPU may write to these pages via their host
                 * physical address while L2 is running, bypassing any
                 * address-translation-based dirty tracking (e.g. EPT write
                 * protection).
                 *
                 * Mark them dirty on every exit from L2 to prevent them from
                 * getting out of sync with dirty tracking.
                 */
                nested_mark_vmcs12_pages_dirty(vcpu);

                if (nested_vmx_reflect_vmexit(vcpu))
                        return 1;
        }

        if (exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) {
                dump_vmcs();
                vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
                vcpu->run->fail_entry.hardware_entry_failure_reason
                        = exit_reason;
                vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
                return 0;
        }

        if (unlikely(vmx->fail)) {
                dump_vmcs();
                vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
                vcpu->run->fail_entry.hardware_entry_failure_reason
                        = vmcs_read32(VM_INSTRUCTION_ERROR);
                vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
                return 0;
        }

        /*
         * Note:
         * Do not try to fix EXIT_REASON_EPT_MISCONFIG if it caused by
         * delivery event since it indicates guest is accessing MMIO.
         * The vm-exit can be triggered again after return to guest that
         * will cause infinite loop.
         */
        if ((vectoring_info & VECTORING_INFO_VALID_MASK) &&
                        (exit_reason != EXIT_REASON_EXCEPTION_NMI &&
                        exit_reason != EXIT_REASON_EPT_VIOLATION &&
                        exit_reason != EXIT_REASON_PML_FULL &&
                        exit_reason != EXIT_REASON_APIC_ACCESS &&
                        exit_reason != EXIT_REASON_TASK_SWITCH)) {
                vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
                vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_DELIVERY_EV;
                vcpu->run->internal.ndata = 3;
                vcpu->run->internal.data[0] = vectoring_info;
                vcpu->run->internal.data[1] = exit_reason;
                vcpu->run->internal.data[2] = vcpu->arch.exit_qualification;
                if (exit_reason == EXIT_REASON_EPT_MISCONFIG) {
                        vcpu->run->internal.ndata++;
                        vcpu->run->internal.data[3] =
                                vmcs_read64(GUEST_PHYSICAL_ADDRESS);
                }
                vcpu->run->internal.data[vcpu->run->internal.ndata++] =
                        vcpu->arch.last_vmentry_cpu;
                return 0;
        }

        if (unlikely(!enable_vnmi &&
                     vmx->loaded_vmcs->soft_vnmi_blocked)) {
                if (!vmx_interrupt_blocked(vcpu)) {
                        vmx->loaded_vmcs->soft_vnmi_blocked = 0;
                } else if (vmx->loaded_vmcs->vnmi_blocked_time > 1000000000LL &&
                           vcpu->arch.nmi_pending) {
                        /*
                         * This CPU don't support us in finding the end of an
                         * NMI-blocked window if the guest runs with IRQs
                         * disabled. So we pull the trigger after 1 s of
                         * futile waiting, but inform the user about this.
                         */
                        printk(KERN_WARNING "%s: Breaking out of NMI-blocked "
                               "state on VCPU %d after 1 s timeout\n",
                               __func__, vcpu->vcpu_id);
                        vmx->loaded_vmcs->soft_vnmi_blocked = 0;
                }
        }

        if (exit_fastpath != EXIT_FASTPATH_NONE)
                return 1;

        if (exit_reason >= kvm_vmx_max_exit_handlers)
                goto unexpected_vmexit;
#ifdef CONFIG_RETPOLINE
        if (exit_reason == EXIT_REASON_MSR_WRITE)
                return kvm_emulate_wrmsr(vcpu);
        else if (exit_reason == EXIT_REASON_PREEMPTION_TIMER)
                return handle_preemption_timer(vcpu);
        else if (exit_reason == EXIT_REASON_INTERRUPT_WINDOW)
                return handle_interrupt_window(vcpu);
        else if (exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT)
                return handle_external_interrupt(vcpu);
        else if (exit_reason == EXIT_REASON_HLT)
                return kvm_emulate_halt(vcpu);
        else if (exit_reason == EXIT_REASON_EPT_MISCONFIG)
                return handle_ept_misconfig(vcpu);
#endif

        exit_reason = array_index_nospec(exit_reason,
                                         kvm_vmx_max_exit_handlers);
        if (!kvm_vmx_exit_handlers[exit_reason])
                goto unexpected_vmexit;

        return kvm_vmx_exit_handlers[exit_reason](vcpu);

unexpected_vmexit:
        vcpu_unimpl(vcpu, "vmx: unexpected exit reason 0x%x\n", exit_reason);
        dump_vmcs();
        vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
        vcpu->run->internal.suberror =
                        KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
        vcpu->run->internal.ndata = 2;
        vcpu->run->internal.data[0] = exit_reason;
        vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
        return 0;
}

/*
 * Software based L1D cache flush which is used when microcode providing
 * the cache control MSR is not loaded.
 *
 * The L1D cache is 32 KiB on Nehalem and later microarchitectures, but to
 * flush it is required to read in 64 KiB because the replacement algorithm
 * is not exactly LRU. This could be sized at runtime via topology
 * information but as all relevant affected CPUs have 32KiB L1D cache size
 * there is no point in doing so.
 */
static noinstr void vmx_l1d_flush(struct kvm_vcpu *vcpu)
{
        int size = PAGE_SIZE << L1D_CACHE_ORDER;

        /*
         * This code is only executed when the the flush mode is 'cond' or
         * 'always'
         */
        if (static_branch_likely(&vmx_l1d_flush_cond)) {
                bool flush_l1d;

                /*
                 * Clear the per-vcpu flush bit, it gets set again
                 * either from vcpu_run() or from one of the unsafe
                 * VMEXIT handlers.
                 */
                flush_l1d = vcpu->arch.l1tf_flush_l1d;
                vcpu->arch.l1tf_flush_l1d = false;

                /*
                 * Clear the per-cpu flush bit, it gets set again from
                 * the interrupt handlers.
                 */
                flush_l1d |= kvm_get_cpu_l1tf_flush_l1d();
                kvm_clear_cpu_l1tf_flush_l1d();

                if (!flush_l1d)
                        return;
        }

        vcpu->stat.l1d_flush++;

        if (static_cpu_has(X86_FEATURE_FLUSH_L1D)) {
                native_wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH);
                return;
        }

        asm volatile(
                /* First ensure the pages are in the TLB */
                "xorl   %%eax, %%eax\n"
                ".Lpopulate_tlb:\n\t"
                "movzbl (%[flush_pages], %%" _ASM_AX "), %%ecx\n\t"
                "addl   $4096, %%eax\n\t"
                "cmpl   %%eax, %[size]\n\t"
                "jne    .Lpopulate_tlb\n\t"
                "xorl   %%eax, %%eax\n\t"
                "cpuid\n\t"
                /* Now fill the cache */
                "xorl   %%eax, %%eax\n"
                ".Lfill_cache:\n"
                "movzbl (%[flush_pages], %%" _ASM_AX "), %%ecx\n\t"
                "addl   $64, %%eax\n\t"
                "cmpl   %%eax, %[size]\n\t"
                "jne    .Lfill_cache\n\t"
                "lfence\n"
                :: [flush_pages] "r" (vmx_l1d_flush_pages),
                    [size] "r" (size)
                : "eax", "ebx", "ecx", "edx");
}

static void update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
{
        struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
        int tpr_threshold;

        if (is_guest_mode(vcpu) &&
                nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW))
                return;

        tpr_threshold = (irr == -1 || tpr < irr) ? 0 : irr;
        if (is_guest_mode(vcpu))
                to_vmx(vcpu)->nested.l1_tpr_threshold = tpr_threshold;
        else
                vmcs_write32(TPR_THRESHOLD, tpr_threshold);
}

void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        u32 sec_exec_control;

        if (!lapic_in_kernel(vcpu))
                return;

        if (!flexpriority_enabled &&
            !cpu_has_vmx_virtualize_x2apic_mode())
                return;

        /* Postpone execution until vmcs01 is the current VMCS. */
        if (is_guest_mode(vcpu)) {
                vmx->nested.change_vmcs01_virtual_apic_mode = true;
                return;
        }

        sec_exec_control = secondary_exec_controls_get(vmx);
        sec_exec_control &= ~(SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
                              SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE);

        switch (kvm_get_apic_mode(vcpu)) {
        case LAPIC_MODE_INVALID:
                WARN_ONCE(true, "Invalid local APIC state");
        case LAPIC_MODE_DISABLED:
                break;
        case LAPIC_MODE_XAPIC:
                if (flexpriority_enabled) {
                        sec_exec_control |=
                                SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
                        kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu);

                        /*
                         * Flush the TLB, reloading the APIC access page will
                         * only do so if its physical address has changed, but
                         * the guest may have inserted a non-APIC mapping into
                         * the TLB while the APIC access page was disabled.
                         */
                        kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
                }
                break;
        case LAPIC_MODE_X2APIC:
                if (cpu_has_vmx_virtualize_x2apic_mode())
                        sec_exec_control |=
                                SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE;
                break;
        }
        secondary_exec_controls_set(vmx, sec_exec_control);

        vmx_update_msr_bitmap(vcpu);
}

static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu)
{
        struct page *page;

        /* Defer reload until vmcs01 is the current VMCS. */
        if (is_guest_mode(vcpu)) {
                to_vmx(vcpu)->nested.reload_vmcs01_apic_access_page = true;
                return;
        }

        if (!(secondary_exec_controls_get(to_vmx(vcpu)) &
            SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES))
                return;

        page = gfn_to_page(vcpu->kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT);
        if (is_error_page(page))
                return;

        vmcs_write64(APIC_ACCESS_ADDR, page_to_phys(page));
        vmx_flush_tlb_current(vcpu);

        /*
         * Do not pin apic access page in memory, the MMU notifier
         * will call us again if it is migrated or swapped out.
         */
        put_page(page);
}

static void vmx_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr)
{
        u16 status;
        u8 old;

        if (max_isr == -1)
                max_isr = 0;

        status = vmcs_read16(GUEST_INTR_STATUS);
        old = status >> 8;
        if (max_isr != old) {
                status &= 0xff;
                status |= max_isr << 8;
                vmcs_write16(GUEST_INTR_STATUS, status);
        }
}

static void vmx_set_rvi(int vector)
{
        u16 status;
        u8 old;

        if (vector == -1)
                vector = 0;

        status = vmcs_read16(GUEST_INTR_STATUS);
        old = (u8)status & 0xff;
        if ((u8)vector != old) {
                status &= ~0xff;
                status |= (u8)vector;
                vmcs_write16(GUEST_INTR_STATUS, status);
        }
}

static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
{
        /*
         * When running L2, updating RVI is only relevant when
         * vmcs12 virtual-interrupt-delivery enabled.
         * However, it can be enabled only when L1 also
         * intercepts external-interrupts and in that case
         * we should not update vmcs02 RVI but instead intercept
         * interrupt. Therefore, do nothing when running L2.
         */
        if (!is_guest_mode(vcpu))
                vmx_set_rvi(max_irr);
}

static int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        int max_irr;
        bool max_irr_updated;

        WARN_ON(!vcpu->arch.apicv_active);
        if (pi_test_on(&vmx->pi_desc)) {
                pi_clear_on(&vmx->pi_desc);
                /*
                 * IOMMU can write to PID.ON, so the barrier matters even on UP.
                 * But on x86 this is just a compiler barrier anyway.
                 */
                smp_mb__after_atomic();
                max_irr_updated =
                        kvm_apic_update_irr(vcpu, vmx->pi_desc.pir, &max_irr);

                /*
                 * If we are running L2 and L1 has a new pending interrupt
                 * which can be injected, we should re-evaluate
                 * what should be done with this new L1 interrupt.
                 * If L1 intercepts external-interrupts, we should
                 * exit from L2 to L1. Otherwise, interrupt should be
                 * delivered directly to L2.
                 */
                if (is_guest_mode(vcpu) && max_irr_updated) {
                        if (nested_exit_on_intr(vcpu))
                                kvm_vcpu_exiting_guest_mode(vcpu);
                        else
                                kvm_make_request(KVM_REQ_EVENT, vcpu);
                }
        } else {
                max_irr = kvm_lapic_find_highest_irr(vcpu);
        }
        vmx_hwapic_irr_update(vcpu, max_irr);
        return max_irr;
}

static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
{
        if (!kvm_vcpu_apicv_active(vcpu))
                return;

        vmcs_write64(EOI_EXIT_BITMAP0, eoi_exit_bitmap[0]);
        vmcs_write64(EOI_EXIT_BITMAP1, eoi_exit_bitmap[1]);
        vmcs_write64(EOI_EXIT_BITMAP2, eoi_exit_bitmap[2]);
        vmcs_write64(EOI_EXIT_BITMAP3, eoi_exit_bitmap[3]);
}

static void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        pi_clear_on(&vmx->pi_desc);
        memset(vmx->pi_desc.pir, 0, sizeof(vmx->pi_desc.pir));
}

void vmx_do_interrupt_nmi_irqoff(unsigned long entry);

static void handle_interrupt_nmi_irqoff(struct kvm_vcpu *vcpu, u32 intr_info)
{
        unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK;
        gate_desc *desc = (gate_desc *)host_idt_base + vector;

        kvm_before_interrupt(vcpu);
        vmx_do_interrupt_nmi_irqoff(gate_offset(desc));
        kvm_after_interrupt(vcpu);
}

static void handle_exception_nmi_irqoff(struct vcpu_vmx *vmx)
{
        u32 intr_info = vmx_get_intr_info(&vmx->vcpu);

        /* if exit due to PF check for async PF */
        if (is_page_fault(intr_info))
                vmx->vcpu.arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
        /* Handle machine checks before interrupts are enabled */
        else if (is_machine_check(intr_info))
                kvm_machine_check();
        /* We need to handle NMIs before interrupts are enabled */
        else if (is_nmi(intr_info))
                handle_interrupt_nmi_irqoff(&vmx->vcpu, intr_info);
}

static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu)
{
        u32 intr_info = vmx_get_intr_info(vcpu);

        if (WARN_ONCE(!is_external_intr(intr_info),
            "KVM: unexpected VM-Exit interrupt info: 0x%x", intr_info))
                return;

        handle_interrupt_nmi_irqoff(vcpu, intr_info);
}

static void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (vmx->exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT)
                handle_external_interrupt_irqoff(vcpu);
        else if (vmx->exit_reason == EXIT_REASON_EXCEPTION_NMI)
                handle_exception_nmi_irqoff(vmx);
}

static bool vmx_has_emulated_msr(u32 index)
{
        switch (index) {
        case MSR_IA32_SMBASE:
                /*
                 * We cannot do SMM unless we can run the guest in big
                 * real mode.
                 */
                return enable_unrestricted_guest || emulate_invalid_guest_state;
        case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
                return nested;
        case MSR_AMD64_VIRT_SPEC_CTRL:
                /* This is AMD only.  */
                return false;
        default:
                return true;
        }
}

static void vmx_recover_nmi_blocking(struct vcpu_vmx *vmx)
{
        u32 exit_intr_info;
        bool unblock_nmi;
        u8 vector;
        bool idtv_info_valid;

        idtv_info_valid = vmx->idt_vectoring_info & VECTORING_INFO_VALID_MASK;

        if (enable_vnmi) {
                if (vmx->loaded_vmcs->nmi_known_unmasked)
                        return;

                exit_intr_info = vmx_get_intr_info(&vmx->vcpu);
                unblock_nmi = (exit_intr_info & INTR_INFO_UNBLOCK_NMI) != 0;
                vector = exit_intr_info & INTR_INFO_VECTOR_MASK;
                /*
                 * SDM 3: 27.7.1.2 (September 2008)
                 * Re-set bit "block by NMI" before VM entry if vmexit caused by
                 * a guest IRET fault.
                 * SDM 3: 23.2.2 (September 2008)
                 * Bit 12 is undefined in any of the following cases:
                 *  If the VM exit sets the valid bit in the IDT-vectoring
                 *   information field.
                 *  If the VM exit is due to a double fault.
                 */
                if ((exit_intr_info & INTR_INFO_VALID_MASK) && unblock_nmi &&
                    vector != DF_VECTOR && !idtv_info_valid)
                        vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
                                      GUEST_INTR_STATE_NMI);
                else
                        vmx->loaded_vmcs->nmi_known_unmasked =
                                !(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO)
                                  & GUEST_INTR_STATE_NMI);
        } else if (unlikely(vmx->loaded_vmcs->soft_vnmi_blocked))
                vmx->loaded_vmcs->vnmi_blocked_time +=
                        ktime_to_ns(ktime_sub(ktime_get(),
                                              vmx->loaded_vmcs->entry_time));
}

static void __vmx_complete_interrupts(struct kvm_vcpu *vcpu,
                                      u32 idt_vectoring_info,
                                      int instr_len_field,
                                      int error_code_field)
{
        u8 vector;
        int type;
        bool idtv_info_valid;

        idtv_info_valid = idt_vectoring_info & VECTORING_INFO_VALID_MASK;

        vcpu->arch.nmi_injected = false;
        kvm_clear_exception_queue(vcpu);
        kvm_clear_interrupt_queue(vcpu);

        if (!idtv_info_valid)
                return;

        kvm_make_request(KVM_REQ_EVENT, vcpu);

        vector = idt_vectoring_info & VECTORING_INFO_VECTOR_MASK;
        type = idt_vectoring_info & VECTORING_INFO_TYPE_MASK;

        switch (type) {
        case INTR_TYPE_NMI_INTR:
                vcpu->arch.nmi_injected = true;
                /*
                 * SDM 3: 27.7.1.2 (September 2008)
                 * Clear bit "block by NMI" before VM entry if a NMI
                 * delivery faulted.
                 */
                vmx_set_nmi_mask(vcpu, false);
                break;
        case INTR_TYPE_SOFT_EXCEPTION:
                vcpu->arch.event_exit_inst_len = vmcs_read32(instr_len_field);
                fallthrough;
        case INTR_TYPE_HARD_EXCEPTION:
                if (idt_vectoring_info & VECTORING_INFO_DELIVER_CODE_MASK) {
                        u32 err = vmcs_read32(error_code_field);
                        kvm_requeue_exception_e(vcpu, vector, err);
                } else
                        kvm_requeue_exception(vcpu, vector);
                break;
        case INTR_TYPE_SOFT_INTR:
                vcpu->arch.event_exit_inst_len = vmcs_read32(instr_len_field);
                fallthrough;
        case INTR_TYPE_EXT_INTR:
                kvm_queue_interrupt(vcpu, vector, type == INTR_TYPE_SOFT_INTR);
                break;
        default:
                break;
        }
}

static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
{
        __vmx_complete_interrupts(&vmx->vcpu, vmx->idt_vectoring_info,
                                  VM_EXIT_INSTRUCTION_LEN,
                                  IDT_VECTORING_ERROR_CODE);
}

static void vmx_cancel_injection(struct kvm_vcpu *vcpu)
{
        __vmx_complete_interrupts(vcpu,
                                  vmcs_read32(VM_ENTRY_INTR_INFO_FIELD),
                                  VM_ENTRY_INSTRUCTION_LEN,
                                  VM_ENTRY_EXCEPTION_ERROR_CODE);

        vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, 0);
}

static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx)
{
        int i, nr_msrs;
        struct perf_guest_switch_msr *msrs;

        msrs = perf_guest_get_msrs(&nr_msrs);

        if (!msrs)
                return;

        for (i = 0; i < nr_msrs; i++)
                if (msrs[i].host == msrs[i].guest)
                        clear_atomic_switch_msr(vmx, msrs[i].msr);
                else
                        add_atomic_switch_msr(vmx, msrs[i].msr, msrs[i].guest,
                                        msrs[i].host, false);
}

static void vmx_update_hv_timer(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        u64 tscl;
        u32 delta_tsc;

        if (vmx->req_immediate_exit) {
                vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, 0);
                vmx->loaded_vmcs->hv_timer_soft_disabled = false;
        } else if (vmx->hv_deadline_tsc != -1) {
                tscl = rdtsc();
                if (vmx->hv_deadline_tsc > tscl)
                        /* set_hv_timer ensures the delta fits in 32-bits */
                        delta_tsc = (u32)((vmx->hv_deadline_tsc - tscl) >>
                                cpu_preemption_timer_multi);
                else
                        delta_tsc = 0;

                vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, delta_tsc);
                vmx->loaded_vmcs->hv_timer_soft_disabled = false;
        } else if (!vmx->loaded_vmcs->hv_timer_soft_disabled) {
                vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, -1);
                vmx->loaded_vmcs->hv_timer_soft_disabled = true;
        }
}

void noinstr vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp)
{
        if (unlikely(host_rsp != vmx->loaded_vmcs->host_state.rsp)) {
                vmx->loaded_vmcs->host_state.rsp = host_rsp;
                vmcs_writel(HOST_RSP, host_rsp);
        }
}

static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
{
        switch (to_vmx(vcpu)->exit_reason) {
        case EXIT_REASON_MSR_WRITE:
                return handle_fastpath_set_msr_irqoff(vcpu);
        case EXIT_REASON_PREEMPTION_TIMER:
                return handle_fastpath_preemption_timer(vcpu);
        default:
                return EXIT_FASTPATH_NONE;
        }
}

bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched);

static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
                                        struct vcpu_vmx *vmx)
{
        /*
         * VMENTER enables interrupts (host state), but the kernel state is
         * interrupts disabled when this is invoked. Also tell RCU about
         * it. This is the same logic as for exit_to_user_mode().
         *
         * This ensures that e.g. latency analysis on the host observes
         * guest mode as interrupt enabled.
         *
         * guest_enter_irqoff() informs context tracking about the
         * transition to guest mode and if enabled adjusts RCU state
         * accordingly.
         */
        instrumentation_begin();
        trace_hardirqs_on_prepare();
        lockdep_hardirqs_on_prepare(CALLER_ADDR0);
        instrumentation_end();

        guest_enter_irqoff();
        lockdep_hardirqs_on(CALLER_ADDR0);

        /* L1D Flush includes CPU buffer clear to mitigate MDS */
        if (static_branch_unlikely(&vmx_l1d_should_flush))
                vmx_l1d_flush(vcpu);
        else if (static_branch_unlikely(&mds_user_clear))
                mds_clear_cpu_buffers();

        if (vcpu->arch.cr2 != native_read_cr2())
                native_write_cr2(vcpu->arch.cr2);

        vmx->fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs,
                                   vmx->loaded_vmcs->launched);

        vcpu->arch.cr2 = native_read_cr2();

        /*
         * VMEXIT disables interrupts (host state), but tracing and lockdep
         * have them in state 'on' as recorded before entering guest mode.
         * Same as enter_from_user_mode().
         *
         * guest_exit_irqoff() restores host context and reinstates RCU if
         * enabled and required.
         *
         * This needs to be done before the below as native_read_msr()
         * contains a tracepoint and x86_spec_ctrl_restore_host() calls
         * into world and some more.
         */
        lockdep_hardirqs_off(CALLER_ADDR0);
        guest_exit_irqoff();

        instrumentation_begin();
        trace_hardirqs_off_finish();
        instrumentation_end();
}

static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
{
        fastpath_t exit_fastpath;
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long cr3, cr4;

reenter_guest:
        /* Record the guest's net vcpu time for enforced NMI injections. */
        if (unlikely(!enable_vnmi &&
                     vmx->loaded_vmcs->soft_vnmi_blocked))
                vmx->loaded_vmcs->entry_time = ktime_get();

        /* Don't enter VMX if guest state is invalid, let the exit handler
           start emulation until we arrive back to a valid state */
        if (vmx->emulation_required)
                return EXIT_FASTPATH_NONE;

        if (vmx->ple_window_dirty) {
                vmx->ple_window_dirty = false;
                vmcs_write32(PLE_WINDOW, vmx->ple_window);
        }

        /*
         * We did this in prepare_switch_to_guest, because it needs to
         * be within srcu_read_lock.
         */
        WARN_ON_ONCE(vmx->nested.need_vmcs12_to_shadow_sync);

        if (kvm_register_is_dirty(vcpu, VCPU_REGS_RSP))
                vmcs_writel(GUEST_RSP, vcpu->arch.regs[VCPU_REGS_RSP]);
        if (kvm_register_is_dirty(vcpu, VCPU_REGS_RIP))
                vmcs_writel(GUEST_RIP, vcpu->arch.regs[VCPU_REGS_RIP]);

        cr3 = __get_current_cr3_fast();
        if (unlikely(cr3 != vmx->loaded_vmcs->host_state.cr3)) {
                vmcs_writel(HOST_CR3, cr3);
                vmx->loaded_vmcs->host_state.cr3 = cr3;
        }

        cr4 = cr4_read_shadow();
        if (unlikely(cr4 != vmx->loaded_vmcs->host_state.cr4)) {
                vmcs_writel(HOST_CR4, cr4);
                vmx->loaded_vmcs->host_state.cr4 = cr4;
        }

        /* When single-stepping over STI and MOV SS, we must clear the
         * corresponding interruptibility bits in the guest state. Otherwise
         * vmentry fails as it then expects bit 14 (BS) in pending debug
         * exceptions being set, but that's not correct for the guest debugging
         * case. */
        if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
                vmx_set_interrupt_shadow(vcpu, 0);

        kvm_load_guest_xsave_state(vcpu);

        pt_guest_enter(vmx);

        atomic_switch_perf_msrs(vmx);

        if (enable_preemption_timer)
                vmx_update_hv_timer(vcpu);

        kvm_wait_lapic_expire(vcpu);

        /*
         * If this vCPU has touched SPEC_CTRL, restore the guest's value if
         * it's non-zero. Since vmentry is serialising on affected CPUs, there
         * is no need to worry about the conditional branch over the wrmsr
         * being speculatively taken.
         */
        x86_spec_ctrl_set_guest(vmx->spec_ctrl, 0);

        /* The actual VMENTER/EXIT is in the .noinstr.text section. */
        vmx_vcpu_enter_exit(vcpu, vmx);

        /*
         * We do not use IBRS in the kernel. If this vCPU has used the
         * SPEC_CTRL MSR it may have left it on; save the value and
         * turn it off. This is much more efficient than blindly adding
         * it to the atomic save/restore list. Especially as the former
         * (Saving guest MSRs on vmexit) doesn't even exist in KVM.
         *
         * For non-nested case:
         * If the L01 MSR bitmap does not intercept the MSR, then we need to
         * save it.
         *
         * For nested case:
         * If the L02 MSR bitmap does not intercept the MSR, then we need to
         * save it.
         */
        if (unlikely(!msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL)))
                vmx->spec_ctrl = native_read_msr(MSR_IA32_SPEC_CTRL);

        x86_spec_ctrl_restore_host(vmx->spec_ctrl, 0);

        /* All fields are clean at this point */
        if (static_branch_unlikely(&enable_evmcs))
                current_evmcs->hv_clean_fields |=
                        HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL;

        if (static_branch_unlikely(&enable_evmcs))
                current_evmcs->hv_vp_id = vcpu->arch.hyperv.vp_index;

        /* MSR_IA32_DEBUGCTLMSR is zeroed on vmexit. Restore it if needed */
        if (vmx->host_debugctlmsr)
                update_debugctlmsr(vmx->host_debugctlmsr);

#ifndef CONFIG_X86_64
        /*
         * The sysexit path does not restore ds/es, so we must set them to
         * a reasonable value ourselves.
         *
         * We can't defer this to vmx_prepare_switch_to_host() since that
         * function may be executed in interrupt context, which saves and
         * restore segments around it, nullifying its effect.
         */
        loadsegment(ds, __USER_DS);
        loadsegment(es, __USER_DS);
#endif

        vmx_register_cache_reset(vcpu);

        pt_guest_exit(vmx);

        kvm_load_host_xsave_state(vcpu);

        vmx->nested.nested_run_pending = 0;
        vmx->idt_vectoring_info = 0;

        if (unlikely(vmx->fail)) {
                vmx->exit_reason = 0xdead;
                return EXIT_FASTPATH_NONE;
        }

        vmx->exit_reason = vmcs_read32(VM_EXIT_REASON);
        if (unlikely((u16)vmx->exit_reason == EXIT_REASON_MCE_DURING_VMENTRY))
                kvm_machine_check();

        trace_kvm_exit(vmx->exit_reason, vcpu, KVM_ISA_VMX);

        if (unlikely(vmx->exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY))
                return EXIT_FASTPATH_NONE;

        vmx->loaded_vmcs->launched = 1;
        vmx->idt_vectoring_info = vmcs_read32(IDT_VECTORING_INFO_FIELD);

        vmx_recover_nmi_blocking(vmx);
        vmx_complete_interrupts(vmx);

        if (is_guest_mode(vcpu))
                return EXIT_FASTPATH_NONE;

        exit_fastpath = vmx_exit_handlers_fastpath(vcpu);
        if (exit_fastpath == EXIT_FASTPATH_REENTER_GUEST) {
                if (!kvm_vcpu_exit_request(vcpu)) {
                        /*
                         * FIXME: this goto should be a loop in vcpu_enter_guest,
                         * but it would incur the cost of a retpoline for now.
                         * Revisit once static calls are available.
                         */
                        if (vcpu->arch.apicv_active)
                                vmx_sync_pir_to_irr(vcpu);
                        goto reenter_guest;
                }
                exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED;
        }

        return exit_fastpath;
}

static void vmx_free_vcpu(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (enable_pml)
                vmx_destroy_pml_buffer(vmx);
        free_vpid(vmx->vpid);
        nested_vmx_free_vcpu(vcpu);
        free_loaded_vmcs(vmx->loaded_vmcs);
}

static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx;
        unsigned long *msr_bitmap;
        int i, cpu, err;

        BUILD_BUG_ON(offsetof(struct vcpu_vmx, vcpu) != 0);
        vmx = to_vmx(vcpu);

        err = -ENOMEM;

        vmx->vpid = allocate_vpid();

        /*
         * If PML is turned on, failure on enabling PML just results in failure
         * of creating the vcpu, therefore we can simplify PML logic (by
         * avoiding dealing with cases, such as enabling PML partially on vcpus
         * for the guest), etc.
         */
        if (enable_pml) {
                vmx->pml_pg = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
                if (!vmx->pml_pg)
                        goto free_vpid;
        }

        BUILD_BUG_ON(ARRAY_SIZE(vmx_msr_index) != MAX_NR_USER_RETURN_MSRS);

        for (i = 0; i < ARRAY_SIZE(vmx_msr_index); ++i) {
                u32 index = vmx_msr_index[i];
                u32 data_low, data_high;
                int j = vmx->nr_uret_msrs;

                if (rdmsr_safe(index, &data_low, &data_high) < 0)
                        continue;
                if (wrmsr_safe(index, data_low, data_high) < 0)
                        continue;

                vmx->guest_uret_msrs[j].index = i;
                vmx->guest_uret_msrs[j].data = 0;
                switch (index) {
                case MSR_IA32_TSX_CTRL:
                        /*
                         * No need to pass TSX_CTRL_CPUID_CLEAR through, so
                         * let's avoid changing CPUID bits under the host
                         * kernel's feet.
                         */
                        vmx->guest_uret_msrs[j].mask = ~(u64)TSX_CTRL_CPUID_CLEAR;
                        break;
                default:
                        vmx->guest_uret_msrs[j].mask = -1ull;
                        break;
                }
                ++vmx->nr_uret_msrs;
        }

        err = alloc_loaded_vmcs(&vmx->vmcs01);
        if (err < 0)
                goto free_pml;

        msr_bitmap = vmx->vmcs01.msr_bitmap;
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_TSC, MSR_TYPE_R);
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_FS_BASE, MSR_TYPE_RW);
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_GS_BASE, MSR_TYPE_RW);
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_KERNEL_GS_BASE, MSR_TYPE_RW);
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_CS, MSR_TYPE_RW);
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_ESP, MSR_TYPE_RW);
        vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_EIP, MSR_TYPE_RW);
        if (kvm_cstate_in_guest(vcpu->kvm)) {
                vmx_disable_intercept_for_msr(msr_bitmap, MSR_CORE_C1_RES, MSR_TYPE_R);
                vmx_disable_intercept_for_msr(msr_bitmap, MSR_CORE_C3_RESIDENCY, MSR_TYPE_R);
                vmx_disable_intercept_for_msr(msr_bitmap, MSR_CORE_C6_RESIDENCY, MSR_TYPE_R);
                vmx_disable_intercept_for_msr(msr_bitmap, MSR_CORE_C7_RESIDENCY, MSR_TYPE_R);
        }
        vmx->msr_bitmap_mode = 0;

        vmx->loaded_vmcs = &vmx->vmcs01;
        cpu = get_cpu();
        vmx_vcpu_load(vcpu, cpu);
        vcpu->cpu = cpu;
        init_vmcs(vmx);
        vmx_vcpu_put(vcpu);
        put_cpu();
        if (cpu_need_virtualize_apic_accesses(vcpu)) {
                err = alloc_apic_access_page(vcpu->kvm);
                if (err)
                        goto free_vmcs;
        }

        if (enable_ept && !enable_unrestricted_guest) {
                err = init_rmode_identity_map(vcpu->kvm);
                if (err)
                        goto free_vmcs;
        }

        if (nested)
                memcpy(&vmx->nested.msrs, &vmcs_config.nested, sizeof(vmx->nested.msrs));
        else
                memset(&vmx->nested.msrs, 0, sizeof(vmx->nested.msrs));

        vmx->nested.posted_intr_nv = -1;
        vmx->nested.current_vmptr = -1ull;

        vcpu->arch.microcode_version = 0x100000000ULL;
        vmx->msr_ia32_feature_control_valid_bits = FEAT_CTL_LOCKED;

        /*
         * Enforce invariant: pi_desc.nv is always either POSTED_INTR_VECTOR
         * or POSTED_INTR_WAKEUP_VECTOR.
         */
        vmx->pi_desc.nv = POSTED_INTR_VECTOR;
        vmx->pi_desc.sn = 1;

        vmx->ept_pointer = INVALID_PAGE;

        return 0;

free_vmcs:
        free_loaded_vmcs(vmx->loaded_vmcs);
free_pml:
        vmx_destroy_pml_buffer(vmx);
free_vpid:
        free_vpid(vmx->vpid);
        return err;
}

#define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
#define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"

static int vmx_vm_init(struct kvm *kvm)
{
        spin_lock_init(&to_kvm_vmx(kvm)->ept_pointer_lock);

        if (!ple_gap)
                kvm->arch.pause_in_guest = true;

        if (boot_cpu_has(X86_BUG_L1TF) && enable_ept) {
                switch (l1tf_mitigation) {
                case L1TF_MITIGATION_OFF:
                case L1TF_MITIGATION_FLUSH_NOWARN:
                        /* 'I explicitly don't care' is set */
                        break;
                case L1TF_MITIGATION_FLUSH:
                case L1TF_MITIGATION_FLUSH_NOSMT:
                case L1TF_MITIGATION_FULL:
                        /*
                         * Warn upon starting the first VM in a potentially
                         * insecure environment.
                         */
                        if (sched_smt_active())
                                pr_warn_once(L1TF_MSG_SMT);
                        if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_NEVER)
                                pr_warn_once(L1TF_MSG_L1D);
                        break;
                case L1TF_MITIGATION_FULL_FORCE:
                        /* Flush is enforced */
                        break;
                }
        }
        kvm_apicv_init(kvm, enable_apicv);
        return 0;
}

static int __init vmx_check_processor_compat(void)
{
        struct vmcs_config vmcs_conf;
        struct vmx_capability vmx_cap;

        if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
            !this_cpu_has(X86_FEATURE_VMX)) {
                pr_err("kvm: VMX is disabled on CPU %d\n", smp_processor_id());
                return -EIO;
        }

        if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0)
                return -EIO;
        if (nested)
                nested_vmx_setup_ctls_msrs(&vmcs_conf.nested, vmx_cap.ept);
        if (memcmp(&vmcs_config, &vmcs_conf, sizeof(struct vmcs_config)) != 0) {
                printk(KERN_ERR "kvm: CPU %d feature inconsistency!\n",
                                smp_processor_id());
                return -EIO;
        }
        return 0;
}

static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
        u8 cache;
        u64 ipat = 0;

        /* We wanted to honor guest CD/MTRR/PAT, but doing so could result in
         * memory aliases with conflicting memory types and sometimes MCEs.
         * We have to be careful as to what are honored and when.
         *
         * For MMIO, guest CD/MTRR are ignored.  The EPT memory type is set to
         * UC.  The effective memory type is UC or WC depending on guest PAT.
         * This was historically the source of MCEs and we want to be
         * conservative.
         *
         * When there is no need to deal with noncoherent DMA (e.g., no VT-d
         * or VT-d has snoop control), guest CD/MTRR/PAT are all ignored.  The
         * EPT memory type is set to WB.  The effective memory type is forced
         * WB.
         *
         * Otherwise, we trust guest.  Guest CD/MTRR/PAT are all honored.  The
         * EPT memory type is used to emulate guest CD/MTRR.
         */

        if (is_mmio) {
                cache = MTRR_TYPE_UNCACHABLE;
                goto exit;
        }

        if (!kvm_arch_has_noncoherent_dma(vcpu->kvm)) {
                ipat = VMX_EPT_IPAT_BIT;
                cache = MTRR_TYPE_WRBACK;
                goto exit;
        }

        if (kvm_read_cr0(vcpu) & X86_CR0_CD) {
                ipat = VMX_EPT_IPAT_BIT;
                if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED))
                        cache = MTRR_TYPE_WRBACK;
                else
                        cache = MTRR_TYPE_UNCACHABLE;
                goto exit;
        }

        cache = kvm_mtrr_get_guest_memory_type(vcpu, gfn);

exit:
        return (cache << VMX_EPT_MT_EPTE_SHIFT) | ipat;
}

static void vmcs_set_secondary_exec_control(struct vcpu_vmx *vmx)
{
        /*
         * These bits in the secondary execution controls field
         * are dynamic, the others are mostly based on the hypervisor
         * architecture and the guest's CPUID.  Do not touch the
         * dynamic bits.
         */
        u32 mask =
                SECONDARY_EXEC_SHADOW_VMCS |
                SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
                SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
                SECONDARY_EXEC_DESC;

        u32 new_ctl = vmx->secondary_exec_control;
        u32 cur_ctl = secondary_exec_controls_get(vmx);

        secondary_exec_controls_set(vmx, (new_ctl & ~mask) | (cur_ctl & mask));
}

/*
 * Generate MSR_IA32_VMX_CR{0,4}_FIXED1 according to CPUID. Only set bits
 * (indicating "allowed-1") if they are supported in the guest's CPUID.
 */
static void nested_vmx_cr_fixed1_bits_update(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct kvm_cpuid_entry2 *entry;

        vmx->nested.msrs.cr0_fixed1 = 0xffffffff;
        vmx->nested.msrs.cr4_fixed1 = X86_CR4_PCE;

#define cr4_fixed1_update(_cr4_mask, _reg, _cpuid_mask) do {            \
        if (entry && (entry->_reg & (_cpuid_mask)))                     \
                vmx->nested.msrs.cr4_fixed1 |= (_cr4_mask);     \
} while (0)

        entry = kvm_find_cpuid_entry(vcpu, 0x1, 0);
        cr4_fixed1_update(X86_CR4_VME,        edx, feature_bit(VME));
        cr4_fixed1_update(X86_CR4_PVI,        edx, feature_bit(VME));
        cr4_fixed1_update(X86_CR4_TSD,        edx, feature_bit(TSC));
        cr4_fixed1_update(X86_CR4_DE,         edx, feature_bit(DE));
        cr4_fixed1_update(X86_CR4_PSE,        edx, feature_bit(PSE));
        cr4_fixed1_update(X86_CR4_PAE,        edx, feature_bit(PAE));
        cr4_fixed1_update(X86_CR4_MCE,        edx, feature_bit(MCE));
        cr4_fixed1_update(X86_CR4_PGE,        edx, feature_bit(PGE));
        cr4_fixed1_update(X86_CR4_OSFXSR,     edx, feature_bit(FXSR));
        cr4_fixed1_update(X86_CR4_OSXMMEXCPT, edx, feature_bit(XMM));
        cr4_fixed1_update(X86_CR4_VMXE,       ecx, feature_bit(VMX));
        cr4_fixed1_update(X86_CR4_SMXE,       ecx, feature_bit(SMX));
        cr4_fixed1_update(X86_CR4_PCIDE,      ecx, feature_bit(PCID));
        cr4_fixed1_update(X86_CR4_OSXSAVE,    ecx, feature_bit(XSAVE));

        entry = kvm_find_cpuid_entry(vcpu, 0x7, 0);
        cr4_fixed1_update(X86_CR4_FSGSBASE,   ebx, feature_bit(FSGSBASE));
        cr4_fixed1_update(X86_CR4_SMEP,       ebx, feature_bit(SMEP));
        cr4_fixed1_update(X86_CR4_SMAP,       ebx, feature_bit(SMAP));
        cr4_fixed1_update(X86_CR4_PKE,        ecx, feature_bit(PKU));
        cr4_fixed1_update(X86_CR4_UMIP,       ecx, feature_bit(UMIP));
        cr4_fixed1_update(X86_CR4_LA57,       ecx, feature_bit(LA57));

#undef cr4_fixed1_update
}

static void nested_vmx_entry_exit_ctls_update(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        if (kvm_mpx_supported()) {
                bool mpx_enabled = guest_cpuid_has(vcpu, X86_FEATURE_MPX);

                if (mpx_enabled) {
                        vmx->nested.msrs.entry_ctls_high |= VM_ENTRY_LOAD_BNDCFGS;
                        vmx->nested.msrs.exit_ctls_high |= VM_EXIT_CLEAR_BNDCFGS;
                } else {
                        vmx->nested.msrs.entry_ctls_high &= ~VM_ENTRY_LOAD_BNDCFGS;
                        vmx->nested.msrs.exit_ctls_high &= ~VM_EXIT_CLEAR_BNDCFGS;
                }
        }
}

static void update_intel_pt_cfg(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct kvm_cpuid_entry2 *best = NULL;
        int i;

        for (i = 0; i < PT_CPUID_LEAVES; i++) {
                best = kvm_find_cpuid_entry(vcpu, 0x14, i);
                if (!best)
                        return;
                vmx->pt_desc.caps[CPUID_EAX + i*PT_CPUID_REGS_NUM] = best->eax;
                vmx->pt_desc.caps[CPUID_EBX + i*PT_CPUID_REGS_NUM] = best->ebx;
                vmx->pt_desc.caps[CPUID_ECX + i*PT_CPUID_REGS_NUM] = best->ecx;
                vmx->pt_desc.caps[CPUID_EDX + i*PT_CPUID_REGS_NUM] = best->edx;
        }

        /* Get the number of configurable Address Ranges for filtering */
        vmx->pt_desc.addr_range = intel_pt_validate_cap(vmx->pt_desc.caps,
                                                PT_CAP_num_address_ranges);

        /* Initialize and clear the no dependency bits */
        vmx->pt_desc.ctl_bitmask = ~(RTIT_CTL_TRACEEN | RTIT_CTL_OS |
                        RTIT_CTL_USR | RTIT_CTL_TSC_EN | RTIT_CTL_DISRETC);

        /*
         * If CPUID.(EAX=14H,ECX=0):EBX[0]=1 CR3Filter can be set otherwise
         * will inject an #GP
         */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_cr3_filtering))
                vmx->pt_desc.ctl_bitmask &= ~RTIT_CTL_CR3EN;

        /*
         * If CPUID.(EAX=14H,ECX=0):EBX[1]=1 CYCEn, CycThresh and
         * PSBFreq can be set
         */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_psb_cyc))
                vmx->pt_desc.ctl_bitmask &= ~(RTIT_CTL_CYCLEACC |
                                RTIT_CTL_CYC_THRESH | RTIT_CTL_PSB_FREQ);

        /*
         * If CPUID.(EAX=14H,ECX=0):EBX[3]=1 MTCEn BranchEn and
         * MTCFreq can be set
         */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_mtc))
                vmx->pt_desc.ctl_bitmask &= ~(RTIT_CTL_MTC_EN |
                                RTIT_CTL_BRANCH_EN | RTIT_CTL_MTC_RANGE);

        /* If CPUID.(EAX=14H,ECX=0):EBX[4]=1 FUPonPTW and PTWEn can be set */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_ptwrite))
                vmx->pt_desc.ctl_bitmask &= ~(RTIT_CTL_FUP_ON_PTW |
                                                        RTIT_CTL_PTW_EN);

        /* If CPUID.(EAX=14H,ECX=0):EBX[5]=1 PwrEvEn can be set */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_power_event_trace))
                vmx->pt_desc.ctl_bitmask &= ~RTIT_CTL_PWR_EVT_EN;

        /* If CPUID.(EAX=14H,ECX=0):ECX[0]=1 ToPA can be set */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_topa_output))
                vmx->pt_desc.ctl_bitmask &= ~RTIT_CTL_TOPA;

        /* If CPUID.(EAX=14H,ECX=0):ECX[3]=1 FabircEn can be set */
        if (intel_pt_validate_cap(vmx->pt_desc.caps, PT_CAP_output_subsys))
                vmx->pt_desc.ctl_bitmask &= ~RTIT_CTL_FABRIC_EN;

        /* unmask address range configure area */
        for (i = 0; i < vmx->pt_desc.addr_range; i++)
                vmx->pt_desc.ctl_bitmask &= ~(0xfULL << (32 + i * 4));
}

static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        /* xsaves_enabled is recomputed in vmx_compute_secondary_exec_control(). */
        vcpu->arch.xsaves_enabled = false;

        if (cpu_has_secondary_exec_ctrls()) {
                vmx_compute_secondary_exec_control(vmx);
                vmcs_set_secondary_exec_control(vmx);
        }

        if (nested_vmx_allowed(vcpu))
                to_vmx(vcpu)->msr_ia32_feature_control_valid_bits |=
                        FEAT_CTL_VMX_ENABLED_INSIDE_SMX |
                        FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX;
        else
                to_vmx(vcpu)->msr_ia32_feature_control_valid_bits &=
                        ~(FEAT_CTL_VMX_ENABLED_INSIDE_SMX |
                          FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX);

        if (nested_vmx_allowed(vcpu)) {
                nested_vmx_cr_fixed1_bits_update(vcpu);
                nested_vmx_entry_exit_ctls_update(vcpu);
        }

        if (boot_cpu_has(X86_FEATURE_INTEL_PT) &&
                        guest_cpuid_has(vcpu, X86_FEATURE_INTEL_PT))
                update_intel_pt_cfg(vcpu);

        if (boot_cpu_has(X86_FEATURE_RTM)) {
                struct vmx_uret_msr *msr;
                msr = find_msr_entry(vmx, MSR_IA32_TSX_CTRL);
                if (msr) {
                        bool enabled = guest_cpuid_has(vcpu, X86_FEATURE_RTM);
                        vmx_set_guest_msr(vmx, msr, enabled ? 0 : TSX_CTRL_RTM_DISABLE);
                }
        }
}

static __init void vmx_set_cpu_caps(void)
{
        kvm_set_cpu_caps();

        /* CPUID 0x1 */
        if (nested)
                kvm_cpu_cap_set(X86_FEATURE_VMX);

        /* CPUID 0x7 */
        if (kvm_mpx_supported())
                kvm_cpu_cap_check_and_set(X86_FEATURE_MPX);
        if (cpu_has_vmx_invpcid())
                kvm_cpu_cap_check_and_set(X86_FEATURE_INVPCID);
        if (vmx_pt_mode_is_host_guest())
                kvm_cpu_cap_check_and_set(X86_FEATURE_INTEL_PT);

        if (vmx_umip_emulated())
                kvm_cpu_cap_set(X86_FEATURE_UMIP);

        /* CPUID 0xD.1 */
        supported_xss = 0;
        if (!cpu_has_vmx_xsaves())
                kvm_cpu_cap_clear(X86_FEATURE_XSAVES);

        /* CPUID 0x80000001 */
        if (!cpu_has_vmx_rdtscp())
                kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);

        if (cpu_has_vmx_waitpkg())
                kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG);
}

static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
{
        to_vmx(vcpu)->req_immediate_exit = true;
}

static int vmx_check_intercept_io(struct kvm_vcpu *vcpu,
                                  struct x86_instruction_info *info)
{
        struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
        unsigned short port;
        bool intercept;
        int size;

        if (info->intercept == x86_intercept_in ||
            info->intercept == x86_intercept_ins) {
                port = info->src_val;
                size = info->dst_bytes;
        } else {
                port = info->dst_val;
                size = info->src_bytes;
        }

        /*
         * If the 'use IO bitmaps' VM-execution control is 0, IO instruction
         * VM-exits depend on the 'unconditional IO exiting' VM-execution
         * control.
         *
         * Otherwise, IO instruction VM-exits are controlled by the IO bitmaps.
         */
        if (!nested_cpu_has(vmcs12, CPU_BASED_USE_IO_BITMAPS))
                intercept = nested_cpu_has(vmcs12,
                                           CPU_BASED_UNCOND_IO_EXITING);
        else
                intercept = nested_vmx_check_io_bitmaps(vcpu, port, size);

        /* FIXME: produce nested vmexit and return X86EMUL_INTERCEPTED.  */
        return intercept ? X86EMUL_UNHANDLEABLE : X86EMUL_CONTINUE;
}

static int vmx_check_intercept(struct kvm_vcpu *vcpu,
                               struct x86_instruction_info *info,
                               enum x86_intercept_stage stage,
                               struct x86_exception *exception)
{
        struct vmcs12 *vmcs12 = get_vmcs12(vcpu);

        switch (info->intercept) {
        /*
         * RDPID causes #UD if disabled through secondary execution controls.
         * Because it is marked as EmulateOnUD, we need to intercept it here.
         */
        case x86_intercept_rdtscp:
                if (!nested_cpu_has2(vmcs12, SECONDARY_EXEC_ENABLE_RDTSCP)) {
                        exception->vector = UD_VECTOR;
                        exception->error_code_valid = false;
                        return X86EMUL_PROPAGATE_FAULT;
                }
                break;

        case x86_intercept_in:
        case x86_intercept_ins:
        case x86_intercept_out:
        case x86_intercept_outs:
                return vmx_check_intercept_io(vcpu, info);

        case x86_intercept_lgdt:
        case x86_intercept_lidt:
        case x86_intercept_lldt:
        case x86_intercept_ltr:
        case x86_intercept_sgdt:
        case x86_intercept_sidt:
        case x86_intercept_sldt:
        case x86_intercept_str:
                if (!nested_cpu_has2(vmcs12, SECONDARY_EXEC_DESC))
                        return X86EMUL_CONTINUE;

                /* FIXME: produce nested vmexit and return X86EMUL_INTERCEPTED.  */
                break;

        /* TODO: check more intercepts... */
        default:
                break;
        }

        return X86EMUL_UNHANDLEABLE;
}

#ifdef CONFIG_X86_64
/* (a << shift) / divisor, return 1 if overflow otherwise 0 */
static inline int u64_shl_div_u64(u64 a, unsigned int shift,
                                  u64 divisor, u64 *result)
{
        u64 low = a << shift, high = a >> (64 - shift);

        /* To avoid the overflow on divq */
        if (high >= divisor)
                return 1;

        /* Low hold the result, high hold rem which is discarded */
        asm("divq %2\n\t" : "=a" (low), "=d" (high) :
            "rm" (divisor), "0" (low), "1" (high));
        *result = low;

        return 0;
}

static int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
                            bool *expired)
{
        struct vcpu_vmx *vmx;
        u64 tscl, guest_tscl, delta_tsc, lapic_timer_advance_cycles;
        struct kvm_timer *ktimer = &vcpu->arch.apic->lapic_timer;

        vmx = to_vmx(vcpu);
        tscl = rdtsc();
        guest_tscl = kvm_read_l1_tsc(vcpu, tscl);
        delta_tsc = max(guest_deadline_tsc, guest_tscl) - guest_tscl;
        lapic_timer_advance_cycles = nsec_to_cycles(vcpu,
                                                    ktimer->timer_advance_ns);

        if (delta_tsc > lapic_timer_advance_cycles)
                delta_tsc -= lapic_timer_advance_cycles;
        else
                delta_tsc = 0;

        /* Convert to host delta tsc if tsc scaling is enabled */
        if (vcpu->arch.tsc_scaling_ratio != kvm_default_tsc_scaling_ratio &&
            delta_tsc && u64_shl_div_u64(delta_tsc,
                                kvm_tsc_scaling_ratio_frac_bits,
                                vcpu->arch.tsc_scaling_ratio, &delta_tsc))
                return -ERANGE;

        /*
         * If the delta tsc can't fit in the 32 bit after the multi shift,
         * we can't use the preemption timer.
         * It's possible that it fits on later vmentries, but checking
         * on every vmentry is costly so we just use an hrtimer.
         */
        if (delta_tsc >> (cpu_preemption_timer_multi + 32))
                return -ERANGE;

        vmx->hv_deadline_tsc = tscl + delta_tsc;
        *expired = !delta_tsc;
        return 0;
}

static void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu)
{
        to_vmx(vcpu)->hv_deadline_tsc = -1;
}
#endif

static void vmx_sched_in(struct kvm_vcpu *vcpu, int cpu)
{
        if (!kvm_pause_in_guest(vcpu->kvm))
                shrink_ple_window(vcpu);
}

static void vmx_slot_enable_log_dirty(struct kvm *kvm,
                                     struct kvm_memory_slot *slot)
{
        if (!kvm_dirty_log_manual_protect_and_init_set(kvm))
                kvm_mmu_slot_leaf_clear_dirty(kvm, slot);
        kvm_mmu_slot_largepage_remove_write_access(kvm, slot);
}

static void vmx_slot_disable_log_dirty(struct kvm *kvm,
                                       struct kvm_memory_slot *slot)
{
        kvm_mmu_slot_set_dirty(kvm, slot);
}

static void vmx_flush_log_dirty(struct kvm *kvm)
{
        kvm_flush_pml_buffers(kvm);
}

static void vmx_enable_log_dirty_pt_masked(struct kvm *kvm,
                                           struct kvm_memory_slot *memslot,
                                           gfn_t offset, unsigned long mask)
{
        kvm_mmu_clear_dirty_pt_masked(kvm, memslot, offset, mask);
}

static int vmx_pre_block(struct kvm_vcpu *vcpu)
{
        if (pi_pre_block(vcpu))
                return 1;

        if (kvm_lapic_hv_timer_in_use(vcpu))
                kvm_lapic_switch_to_sw_timer(vcpu);

        return 0;
}

static void vmx_post_block(struct kvm_vcpu *vcpu)
{
        if (kvm_x86_ops.set_hv_timer)
                kvm_lapic_switch_to_hv_timer(vcpu);

        pi_post_block(vcpu);
}

static void vmx_setup_mce(struct kvm_vcpu *vcpu)
{
        if (vcpu->arch.mcg_cap & MCG_LMCE_P)
                to_vmx(vcpu)->msr_ia32_feature_control_valid_bits |=
                        FEAT_CTL_LMCE_ENABLED;
        else
                to_vmx(vcpu)->msr_ia32_feature_control_valid_bits &=
                        ~FEAT_CTL_LMCE_ENABLED;
}

static int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
        /* we need a nested vmexit to enter SMM, postpone if run is pending */
        if (to_vmx(vcpu)->nested.nested_run_pending)
                return -EBUSY;
        return !is_smm(vcpu);
}

static int vmx_pre_enter_smm(struct kvm_vcpu *vcpu, char *smstate)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);

        vmx->nested.smm.guest_mode = is_guest_mode(vcpu);
        if (vmx->nested.smm.guest_mode)
                nested_vmx_vmexit(vcpu, -1, 0, 0);

        vmx->nested.smm.vmxon = vmx->nested.vmxon;
        vmx->nested.vmxon = false;
        vmx_clear_hlt(vcpu);
        return 0;
}

static int vmx_pre_leave_smm(struct kvm_vcpu *vcpu, const char *smstate)
{
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        int ret;

        if (vmx->nested.smm.vmxon) {
                vmx->nested.vmxon = true;
                vmx->nested.smm.vmxon = false;
        }

        if (vmx->nested.smm.guest_mode) {
                ret = nested_vmx_enter_non_root_mode(vcpu, false);
                if (ret)
                        return ret;

                vmx->nested.smm.guest_mode = false;
        }
        return 0;
}

static void enable_smi_window(struct kvm_vcpu *vcpu)
{
        /* RSM will cause a vmexit anyway.  */
}

static bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
{
        return to_vmx(vcpu)->nested.vmxon;
}

static void vmx_migrate_timers(struct kvm_vcpu *vcpu)
{
        if (is_guest_mode(vcpu)) {
                struct hrtimer *timer = &to_vmx(vcpu)->nested.preemption_timer;

                if (hrtimer_try_to_cancel(timer) == 1)
                        hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED);
        }
}

static void hardware_unsetup(void)
{
        if (nested)
                nested_vmx_hardware_unsetup();

        free_kvm_area();
}

static bool vmx_check_apicv_inhibit_reasons(ulong bit)
{
        ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) |
                          BIT(APICV_INHIBIT_REASON_HYPERV);

        return supported & BIT(bit);
}

static struct kvm_x86_ops vmx_x86_ops __initdata = {
        .hardware_unsetup = hardware_unsetup,

        .hardware_enable = hardware_enable,
        .hardware_disable = hardware_disable,
        .cpu_has_accelerated_tpr = report_flexpriority,
        .has_emulated_msr = vmx_has_emulated_msr,

        .vm_size = sizeof(struct kvm_vmx),
        .vm_init = vmx_vm_init,

        .vcpu_create = vmx_create_vcpu,
        .vcpu_free = vmx_free_vcpu,
        .vcpu_reset = vmx_vcpu_reset,

        .prepare_guest_switch = vmx_prepare_switch_to_guest,
        .vcpu_load = vmx_vcpu_load,
        .vcpu_put = vmx_vcpu_put,

        .update_exception_bitmap = update_exception_bitmap,
        .get_msr_feature = vmx_get_msr_feature,
        .get_msr = vmx_get_msr,
        .set_msr = vmx_set_msr,
        .get_segment_base = vmx_get_segment_base,
        .get_segment = vmx_get_segment,
        .set_segment = vmx_set_segment,
        .get_cpl = vmx_get_cpl,
        .get_cs_db_l_bits = vmx_get_cs_db_l_bits,
        .set_cr0 = vmx_set_cr0,
        .set_cr4 = vmx_set_cr4,
        .set_efer = vmx_set_efer,
        .get_idt = vmx_get_idt,
        .set_idt = vmx_set_idt,
        .get_gdt = vmx_get_gdt,
        .set_gdt = vmx_set_gdt,
        .set_dr7 = vmx_set_dr7,
        .sync_dirty_debug_regs = vmx_sync_dirty_debug_regs,
        .cache_reg = vmx_cache_reg,
        .get_rflags = vmx_get_rflags,
        .set_rflags = vmx_set_rflags,

        .tlb_flush_all = vmx_flush_tlb_all,
        .tlb_flush_current = vmx_flush_tlb_current,
        .tlb_flush_gva = vmx_flush_tlb_gva,
        .tlb_flush_guest = vmx_flush_tlb_guest,

        .run = vmx_vcpu_run,
        .handle_exit = vmx_handle_exit,
        .skip_emulated_instruction = vmx_skip_emulated_instruction,
        .update_emulated_instruction = vmx_update_emulated_instruction,
        .set_interrupt_shadow = vmx_set_interrupt_shadow,
        .get_interrupt_shadow = vmx_get_interrupt_shadow,
        .patch_hypercall = vmx_patch_hypercall,
        .set_irq = vmx_inject_irq,
        .set_nmi = vmx_inject_nmi,
        .queue_exception = vmx_queue_exception,
        .cancel_injection = vmx_cancel_injection,
        .interrupt_allowed = vmx_interrupt_allowed,
        .nmi_allowed = vmx_nmi_allowed,
        .get_nmi_mask = vmx_get_nmi_mask,
        .set_nmi_mask = vmx_set_nmi_mask,
        .enable_nmi_window = enable_nmi_window,
        .enable_irq_window = enable_irq_window,
        .update_cr8_intercept = update_cr8_intercept,
        .set_virtual_apic_mode = vmx_set_virtual_apic_mode,
        .set_apic_access_page_addr = vmx_set_apic_access_page_addr,
        .refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
        .load_eoi_exitmap = vmx_load_eoi_exitmap,
        .apicv_post_state_restore = vmx_apicv_post_state_restore,
        .check_apicv_inhibit_reasons = vmx_check_apicv_inhibit_reasons,
        .hwapic_irr_update = vmx_hwapic_irr_update,
        .hwapic_isr_update = vmx_hwapic_isr_update,
        .guest_apic_has_interrupt = vmx_guest_apic_has_interrupt,
        .sync_pir_to_irr = vmx_sync_pir_to_irr,
        .deliver_posted_interrupt = vmx_deliver_posted_interrupt,
        .dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,

        .set_tss_addr = vmx_set_tss_addr,
        .set_identity_map_addr = vmx_set_identity_map_addr,
        .get_mt_mask = vmx_get_mt_mask,

        .get_exit_info = vmx_get_exit_info,

        .vcpu_after_set_cpuid = vmx_vcpu_after_set_cpuid,

        .has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,

        .write_l1_tsc_offset = vmx_write_l1_tsc_offset,

        .load_mmu_pgd = vmx_load_mmu_pgd,

        .check_intercept = vmx_check_intercept,
        .handle_exit_irqoff = vmx_handle_exit_irqoff,

        .request_immediate_exit = vmx_request_immediate_exit,

        .sched_in = vmx_sched_in,

        .slot_enable_log_dirty = vmx_slot_enable_log_dirty,
        .slot_disable_log_dirty = vmx_slot_disable_log_dirty,
        .flush_log_dirty = vmx_flush_log_dirty,
        .enable_log_dirty_pt_masked = vmx_enable_log_dirty_pt_masked,

        .pre_block = vmx_pre_block,
        .post_block = vmx_post_block,

        .pmu_ops = &intel_pmu_ops,
        .nested_ops = &vmx_nested_ops,

        .update_pi_irte = pi_update_irte,

#ifdef CONFIG_X86_64
        .set_hv_timer = vmx_set_hv_timer,
        .cancel_hv_timer = vmx_cancel_hv_timer,
#endif

        .setup_mce = vmx_setup_mce,

        .smi_allowed = vmx_smi_allowed,
        .pre_enter_smm = vmx_pre_enter_smm,
        .pre_leave_smm = vmx_pre_leave_smm,
        .enable_smi_window = enable_smi_window,

        .can_emulate_instruction = vmx_can_emulate_instruction,
        .apic_init_signal_blocked = vmx_apic_init_signal_blocked,
        .migrate_timers = vmx_migrate_timers,
};

static __init int hardware_setup(void)
{
        unsigned long host_bndcfgs;
        struct desc_ptr dt;
        int r, i, ept_lpage_level;

        store_idt(&dt);
        host_idt_base = dt.address;

        for (i = 0; i < ARRAY_SIZE(vmx_msr_index); ++i)
                kvm_define_user_return_msr(i, vmx_msr_index[i]);

        if (setup_vmcs_config(&vmcs_config, &vmx_capability) < 0)
                return -EIO;

        if (boot_cpu_has(X86_FEATURE_NX))
                kvm_enable_efer_bits(EFER_NX);

        if (boot_cpu_has(X86_FEATURE_MPX)) {
                rdmsrl(MSR_IA32_BNDCFGS, host_bndcfgs);
                WARN_ONCE(host_bndcfgs, "KVM: BNDCFGS in host will be lost");
        }

        if (!cpu_has_vmx_mpx())
                supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS |
                                    XFEATURE_MASK_BNDCSR);

        if (!cpu_has_vmx_vpid() || !cpu_has_vmx_invvpid() ||
            !(cpu_has_vmx_invvpid_single() || cpu_has_vmx_invvpid_global()))
                enable_vpid = 0;

        if (!cpu_has_vmx_ept() ||
            !cpu_has_vmx_ept_4levels() ||
            !cpu_has_vmx_ept_mt_wb() ||
            !cpu_has_vmx_invept_global())
                enable_ept = 0;

        if (!cpu_has_vmx_ept_ad_bits() || !enable_ept)
                enable_ept_ad_bits = 0;

        if (!cpu_has_vmx_unrestricted_guest() || !enable_ept)
                enable_unrestricted_guest = 0;

        if (!cpu_has_vmx_flexpriority())
                flexpriority_enabled = 0;

        if (!cpu_has_virtual_nmis())
                enable_vnmi = 0;

        /*
         * set_apic_access_page_addr() is used to reload apic access
         * page upon invalidation.  No need to do anything if not
         * using the APIC_ACCESS_ADDR VMCS field.
         */
        if (!flexpriority_enabled)
                vmx_x86_ops.set_apic_access_page_addr = NULL;

        if (!cpu_has_vmx_tpr_shadow())
                vmx_x86_ops.update_cr8_intercept = NULL;

#if IS_ENABLED(CONFIG_HYPERV)
        if (ms_hyperv.nested_features & HV_X64_NESTED_GUEST_MAPPING_FLUSH
            && enable_ept) {
                vmx_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
                vmx_x86_ops.tlb_remote_flush_with_range =
                                hv_remote_flush_tlb_with_range;
        }
#endif

        if (!cpu_has_vmx_ple()) {
                ple_gap = 0;
                ple_window = 0;
                ple_window_grow = 0;
                ple_window_max = 0;
                ple_window_shrink = 0;
        }

        if (!cpu_has_vmx_apicv()) {
                enable_apicv = 0;
                vmx_x86_ops.sync_pir_to_irr = NULL;
        }

        if (cpu_has_vmx_tsc_scaling()) {
                kvm_has_tsc_control = true;
                kvm_max_tsc_scaling_ratio = KVM_VMX_TSC_MULTIPLIER_MAX;
                kvm_tsc_scaling_ratio_frac_bits = 48;
        }

        set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */

        if (enable_ept)
                vmx_enable_tdp();

        if (!enable_ept)
                ept_lpage_level = 0;
        else if (cpu_has_vmx_ept_1g_page())
                ept_lpage_level = PG_LEVEL_1G;
        else if (cpu_has_vmx_ept_2m_page())
                ept_lpage_level = PG_LEVEL_2M;
        else
                ept_lpage_level = PG_LEVEL_4K;
        kvm_configure_mmu(enable_ept, vmx_get_max_tdp_level(), ept_lpage_level);

        /*
         * Only enable PML when hardware supports PML feature, and both EPT
         * and EPT A/D bit features are enabled -- PML depends on them to work.
         */
        if (!enable_ept || !enable_ept_ad_bits || !cpu_has_vmx_pml())
                enable_pml = 0;

        if (!enable_pml) {
                vmx_x86_ops.slot_enable_log_dirty = NULL;
                vmx_x86_ops.slot_disable_log_dirty = NULL;
                vmx_x86_ops.flush_log_dirty = NULL;
                vmx_x86_ops.enable_log_dirty_pt_masked = NULL;
        }

        if (!cpu_has_vmx_preemption_timer())
                enable_preemption_timer = false;

        if (enable_preemption_timer) {
                u64 use_timer_freq = 5000ULL * 1000 * 1000;
                u64 vmx_msr;

                rdmsrl(MSR_IA32_VMX_MISC, vmx_msr);
                cpu_preemption_timer_multi =
                        vmx_msr & VMX_MISC_PREEMPTION_TIMER_RATE_MASK;

                if (tsc_khz)
                        use_timer_freq = (u64)tsc_khz * 1000;
                use_timer_freq >>= cpu_preemption_timer_multi;

                /*
                 * KVM "disables" the preemption timer by setting it to its max
                 * value.  Don't use the timer if it might cause spurious exits
                 * at a rate faster than 0.1 Hz (of uninterrupted guest time).
                 */
                if (use_timer_freq > 0xffffffffu / 10)
                        enable_preemption_timer = false;
        }

        if (!enable_preemption_timer) {
                vmx_x86_ops.set_hv_timer = NULL;
                vmx_x86_ops.cancel_hv_timer = NULL;
                vmx_x86_ops.request_immediate_exit = __kvm_request_immediate_exit;
        }

        kvm_set_posted_intr_wakeup_handler(pi_wakeup_handler);

        kvm_mce_cap_supported |= MCG_LMCE_P;

        if (pt_mode != PT_MODE_SYSTEM && pt_mode != PT_MODE_HOST_GUEST)
                return -EINVAL;
        if (!enable_ept || !cpu_has_vmx_intel_pt())
                pt_mode = PT_MODE_SYSTEM;

        if (nested) {
                nested_vmx_setup_ctls_msrs(&vmcs_config.nested,
                                           vmx_capability.ept);

                r = nested_vmx_hardware_setup(kvm_vmx_exit_handlers);
                if (r)
                        return r;
        }

        vmx_set_cpu_caps();

        r = alloc_kvm_area();
        if (r)
                nested_vmx_hardware_unsetup();
        return r;
}

static struct kvm_x86_init_ops vmx_init_ops __initdata = {
        .cpu_has_kvm_support = cpu_has_kvm_support,
        .disabled_by_bios = vmx_disabled_by_bios,
        .check_processor_compatibility = vmx_check_processor_compat,
        .hardware_setup = hardware_setup,

        .runtime_ops = &vmx_x86_ops,
};

static void vmx_cleanup_l1d_flush(void)
{
        if (vmx_l1d_flush_pages) {
                free_pages((unsigned long)vmx_l1d_flush_pages, L1D_CACHE_ORDER);
                vmx_l1d_flush_pages = NULL;
        }
        /* Restore state so sysfs ignores VMX */
        l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO;
}

static void vmx_exit(void)
{
#ifdef CONFIG_KEXEC_CORE
        RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
        synchronize_rcu();
#endif

        kvm_exit();

#if IS_ENABLED(CONFIG_HYPERV)
        if (static_branch_unlikely(&enable_evmcs)) {
                int cpu;
                struct hv_vp_assist_page *vp_ap;
                /*
                 * Reset everything to support using non-enlightened VMCS
                 * access later (e.g. when we reload the module with
                 * enlightened_vmcs=0)
                 */
                for_each_online_cpu(cpu) {
                        vp_ap = hv_get_vp_assist_page(cpu);

                        if (!vp_ap)
                                continue;

                        vp_ap->nested_control.features.directhypercall = 0;
                        vp_ap->current_nested_vmcs = 0;
                        vp_ap->enlighten_vmentry = 0;
                }

                static_branch_disable(&enable_evmcs);
        }
#endif
        vmx_cleanup_l1d_flush();
}
module_exit(vmx_exit);

static int __init vmx_init(void)
{
        int r, cpu;

#if IS_ENABLED(CONFIG_HYPERV)
        /*
         * Enlightened VMCS usage should be recommended and the host needs
         * to support eVMCS v1 or above. We can also disable eVMCS support
         * with module parameter.
         */
        if (enlightened_vmcs &&
            ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED &&
            (ms_hyperv.nested_features & HV_X64_ENLIGHTENED_VMCS_VERSION) >=
            KVM_EVMCS_VERSION) {
                int cpu;

                /* Check that we have assist pages on all online CPUs */
                for_each_online_cpu(cpu) {
                        if (!hv_get_vp_assist_page(cpu)) {
                                enlightened_vmcs = false;
                                break;
                        }
                }

                if (enlightened_vmcs) {
                        pr_info("KVM: vmx: using Hyper-V Enlightened VMCS\n");
                        static_branch_enable(&enable_evmcs);
                }

                if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
                        vmx_x86_ops.enable_direct_tlbflush
                                = hv_enable_direct_tlbflush;

        } else {
                enlightened_vmcs = false;
        }
#endif

        r = kvm_init(&vmx_init_ops, sizeof(struct vcpu_vmx),
                     __alignof__(struct vcpu_vmx), THIS_MODULE);
        if (r)
                return r;

        /*
         * Must be called after kvm_init() so enable_ept is properly set
         * up. Hand the parameter mitigation value in which was stored in
         * the pre module init parser. If no parameter was given, it will
         * contain 'auto' which will be turned into the default 'cond'
         * mitigation mode.
         */
        r = vmx_setup_l1d_flush(vmentry_l1d_flush_param);
        if (r) {
                vmx_exit();
                return r;
        }

        for_each_possible_cpu(cpu) {
                INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu));

                pi_init(cpu);
        }

#ifdef CONFIG_KEXEC_CORE
        rcu_assign_pointer(crash_vmclear_loaded_vmcss,
                           crash_vmclear_local_loaded_vmcss);
#endif
        vmx_check_vmcs12_offsets();

        /*
         * Intel processors don't have problems with
         * GUEST_MAXPHYADDR < HOST_MAXPHYADDR so enable
         * it for VMX by default
         */
        allow_smaller_maxphyaddr = true;

        return 0;
}
module_init(vmx_init);