arch/x86/kvm/svm/nested.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Kernel-based Virtual Machine driver for Linux
   4  *
   5  * AMD SVM support
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
   9  *
  10  * Authors:
  11  *   Yaniv Kamay  <yaniv@qumranet.com>
  12  *   Avi Kivity   <avi@qumranet.com>
  13  */
  14
  15 #define pr_fmt(fmt) "SVM: " fmt
  16
  17 #include <linux/kvm_types.h>
  18 #include <linux/kvm_host.h>
  19 #include <linux/kernel.h>
  20
  21 #include <asm/msr-index.h>
  22 #include <asm/debugreg.h>
  23
  24 #include "kvm_emulate.h"
  25 #include "trace.h"
  26 #include "mmu.h"
  27 #include "x86.h"
  28 #include "cpuid.h"
  29 #include "lapic.h"
  30 #include "svm.h"
  31
  32 static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
  33                                        struct x86_exception *fault)
  34 {
  35         struct vcpu_svm *svm = to_svm(vcpu);
  36
  37         if (svm->vmcb->control.exit_code != SVM_EXIT_NPF) {
  38                 /*
  39                  * TODO: track the cause of the nested page fault, and
  40                  * correctly fill in the high bits of exit_info_1.
  41                  */
  42                 svm->vmcb->control.exit_code = SVM_EXIT_NPF;
  43                 svm->vmcb->control.exit_code_hi = 0;
  44                 svm->vmcb->control.exit_info_1 = (1ULL << 32);
  45                 svm->vmcb->control.exit_info_2 = fault->address;
  46         }
  47
  48         svm->vmcb->control.exit_info_1 &= ~0xffffffffULL;
  49         svm->vmcb->control.exit_info_1 |= fault->error_code;
  50
  51         nested_svm_vmexit(svm);
  52 }
  53
  54 static void svm_inject_page_fault_nested(struct kvm_vcpu *vcpu, struct x86_exception *fault)
  55 {
  56        struct vcpu_svm *svm = to_svm(vcpu);
  57        WARN_ON(!is_guest_mode(vcpu));
  58
  59        if (vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_EXCEPTION_OFFSET + PF_VECTOR) &&
  60            !svm->nested.nested_run_pending) {
  61                svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + PF_VECTOR;
  62                svm->vmcb->control.exit_code_hi = 0;
  63                svm->vmcb->control.exit_info_1 = fault->error_code;
  64                svm->vmcb->control.exit_info_2 = fault->address;
  65                nested_svm_vmexit(svm);
  66        } else {
  67                kvm_inject_page_fault(vcpu, fault);
  68        }
  69 }
  70
  71 static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index)
  72 {
  73         struct vcpu_svm *svm = to_svm(vcpu);
  74         u64 cr3 = svm->nested.ctl.nested_cr3;
  75         u64 pdpte;
  76         int ret;
  77
  78         ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(cr3), &pdpte,
  79                                        offset_in_page(cr3) + index * 8, 8);
  80         if (ret)
  81                 return 0;
  82         return pdpte;
  83 }
  84
  85 static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu)
  86 {
  87         struct vcpu_svm *svm = to_svm(vcpu);
  88
  89         return svm->nested.ctl.nested_cr3;
  90 }
  91
  92 static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
  93 {
  94         struct vcpu_svm *svm = to_svm(vcpu);
  95         struct vmcb *hsave = svm->nested.hsave;
  96
  97         WARN_ON(mmu_is_nested(vcpu));
  98
  99         vcpu->arch.mmu = &vcpu->arch.guest_mmu;
 100         kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, hsave->save.cr4, hsave->save.efer,
 101                                 svm->nested.ctl.nested_cr3);
 102         vcpu->arch.mmu->get_guest_pgd     = nested_svm_get_tdp_cr3;
 103         vcpu->arch.mmu->get_pdptr         = nested_svm_get_tdp_pdptr;
 104         vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit;
 105         reset_shadow_zero_bits_mask(vcpu, vcpu->arch.mmu);
 106         vcpu->arch.walk_mmu              = &vcpu->arch.nested_mmu;
 107 }
 108
 109 static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)
 110 {
 111         vcpu->arch.mmu = &vcpu->arch.root_mmu;
 112         vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;
 113 }
 114
 115 void recalc_intercepts(struct vcpu_svm *svm)
 116 {
 117         struct vmcb_control_area *c, *h, *g;
 118         unsigned int i;
 119
 120         vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
 121
 122         if (!is_guest_mode(&svm->vcpu))
 123                 return;
 124
 125         c = &svm->vmcb->control;
 126         h = &svm->nested.hsave->control;
 127         g = &svm->nested.ctl;
 128
 129         for (i = 0; i < MAX_INTERCEPT; i++)
 130                 c->intercepts[i] = h->intercepts[i];
 131
 132         if (g->int_ctl & V_INTR_MASKING_MASK) {
 133                 /* We only want the cr8 intercept bits of L1 */
 134                 vmcb_clr_intercept(c, INTERCEPT_CR8_READ);
 135                 vmcb_clr_intercept(c, INTERCEPT_CR8_WRITE);
 136
 137                 /*
 138                  * Once running L2 with HF_VINTR_MASK, EFLAGS.IF does not
 139                  * affect any interrupt we may want to inject; therefore,
 140                  * interrupt window vmexits are irrelevant to L0.
 141                  */
 142                 vmcb_clr_intercept(c, INTERCEPT_VINTR);
 143         }
 144
 145         /* We don't want to see VMMCALLs from a nested guest */
 146         vmcb_clr_intercept(c, INTERCEPT_VMMCALL);
 147
 148         for (i = 0; i < MAX_INTERCEPT; i++)
 149                 c->intercepts[i] |= g->intercepts[i];
 150 }
 151
 152 static void copy_vmcb_control_area(struct vmcb_control_area *dst,
 153                                    struct vmcb_control_area *from)
 154 {
 155         unsigned int i;
 156
 157         for (i = 0; i < MAX_INTERCEPT; i++)
 158                 dst->intercepts[i] = from->intercepts[i];
 159
 160         dst->iopm_base_pa         = from->iopm_base_pa;
 161         dst->msrpm_base_pa        = from->msrpm_base_pa;
 162         dst->tsc_offset           = from->tsc_offset;
 163         /* asid not copied, it is handled manually for svm->vmcb.  */
 164         dst->tlb_ctl              = from->tlb_ctl;
 165         dst->int_ctl              = from->int_ctl;
 166         dst->int_vector           = from->int_vector;
 167         dst->int_state            = from->int_state;
 168         dst->exit_code            = from->exit_code;
 169         dst->exit_code_hi         = from->exit_code_hi;
 170         dst->exit_info_1          = from->exit_info_1;
 171         dst->exit_info_2          = from->exit_info_2;
 172         dst->exit_int_info        = from->exit_int_info;
 173         dst->exit_int_info_err    = from->exit_int_info_err;
 174         dst->nested_ctl           = from->nested_ctl;
 175         dst->event_inj            = from->event_inj;
 176         dst->event_inj_err        = from->event_inj_err;
 177         dst->nested_cr3           = from->nested_cr3;
 178         dst->virt_ext              = from->virt_ext;
 179         dst->pause_filter_count   = from->pause_filter_count;
 180         dst->pause_filter_thresh  = from->pause_filter_thresh;
 181 }
 182
 183 static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
 184 {
 185         /*
 186          * This function merges the msr permission bitmaps of kvm and the
 187          * nested vmcb. It is optimized in that it only merges the parts where
 188          * the kvm msr permission bitmap may contain zero bits
 189          */
 190         int i;
 191
 192         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
 193                 return true;
 194
 195         for (i = 0; i < MSRPM_OFFSETS; i++) {
 196                 u32 value, p;
 197                 u64 offset;
 198
 199                 if (msrpm_offsets[i] == 0xffffffff)
 200                         break;
 201
 202                 p      = msrpm_offsets[i];
 203                 offset = svm->nested.ctl.msrpm_base_pa + (p * 4);
 204
 205                 if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4))
 206                         return false;
 207
 208                 svm->nested.msrpm[p] = svm->msrpm[p] | value;
 209         }
 210
 211         svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm));
 212
 213         return true;
 214 }
 215
 216 static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
 217 {
 218         struct vcpu_svm *svm = to_svm(vcpu);
 219
 220         if (WARN_ON(!is_guest_mode(vcpu)))
 221                 return true;
 222
 223         if (!nested_svm_vmrun_msrpm(svm)) {
 224                 vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 225                 vcpu->run->internal.suberror =
 226                         KVM_INTERNAL_ERROR_EMULATION;
 227                 vcpu->run->internal.ndata = 0;
 228                 return false;
 229         }
 230
 231         return true;
 232 }
 233
 234 static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
 235 {
 236         if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0)
 237                 return false;
 238
 239         if (control->asid == 0)
 240                 return false;
 241
 242         if ((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) &&
 243             !npt_enabled)
 244                 return false;
 245
 246         return true;
 247 }
 248
 249 static bool nested_vmcb_check_save(struct vcpu_svm *svm, struct vmcb *vmcb12)
 250 {
 251         struct kvm_vcpu *vcpu = &svm->vcpu;
 252         bool vmcb12_lma;
 253
 254         /*
 255          * FIXME: these should be done after copying the fields,
 256          * to avoid TOC/TOU races.  For these save area checks
 257          * the possible damage is limited since kvm_set_cr0 and
 258          * kvm_set_cr4 handle failure; EFER_SVME is an exception
 259          * so it is force-set later in nested_prepare_vmcb_save.
 260          */
 261         if ((vmcb12->save.efer & EFER_SVME) == 0)
 262                 return false;
 263
 264         if (((vmcb12->save.cr0 & X86_CR0_CD) == 0) && (vmcb12->save.cr0 & X86_CR0_NW))
 265                 return false;
 266
 267         if (!kvm_dr6_valid(vmcb12->save.dr6) || !kvm_dr7_valid(vmcb12->save.dr7))
 268                 return false;
 269
 270         vmcb12_lma = (vmcb12->save.efer & EFER_LME) && (vmcb12->save.cr0 & X86_CR0_PG);
 271
 272         if (vmcb12_lma) {
 273                 if (!(vmcb12->save.cr4 & X86_CR4_PAE) ||
 274                     !(vmcb12->save.cr0 & X86_CR0_PE) ||
 275                     kvm_vcpu_is_illegal_gpa(vcpu, vmcb12->save.cr3))
 276                         return false;
 277         }
 278         if (!kvm_is_valid_cr4(&svm->vcpu, vmcb12->save.cr4))
 279                 return false;
 280
 281         return true;
 282 }
 283
 284 static void load_nested_vmcb_control(struct vcpu_svm *svm,
 285                                      struct vmcb_control_area *control)
 286 {
 287         copy_vmcb_control_area(&svm->nested.ctl, control);
 288
 289         /* Copy it here because nested_svm_check_controls will check it.  */
 290         svm->nested.ctl.asid           = control->asid;
 291         svm->nested.ctl.msrpm_base_pa &= ~0x0fffULL;
 292         svm->nested.ctl.iopm_base_pa  &= ~0x0fffULL;
 293 }
 294
 295 /*
 296  * Synchronize fields that are written by the processor, so that
 297  * they can be copied back into the nested_vmcb.
 298  */
 299 void sync_nested_vmcb_control(struct vcpu_svm *svm)
 300 {
 301         u32 mask;
 302         svm->nested.ctl.event_inj      = svm->vmcb->control.event_inj;
 303         svm->nested.ctl.event_inj_err  = svm->vmcb->control.event_inj_err;
 304
 305         /* Only a few fields of int_ctl are written by the processor.  */
 306         mask = V_IRQ_MASK | V_TPR_MASK;
 307         if (!(svm->nested.ctl.int_ctl & V_INTR_MASKING_MASK) &&
 308             svm_is_intercept(svm, INTERCEPT_VINTR)) {
 309                 /*
 310                  * In order to request an interrupt window, L0 is usurping
 311                  * svm->vmcb->control.int_ctl and possibly setting V_IRQ
 312                  * even if it was clear in L1's VMCB.  Restoring it would be
 313                  * wrong.  However, in this case V_IRQ will remain true until
 314                  * interrupt_window_interception calls svm_clear_vintr and
 315                  * restores int_ctl.  We can just leave it aside.
 316                  */
 317                 mask &= ~V_IRQ_MASK;
 318         }
 319         svm->nested.ctl.int_ctl        &= ~mask;
 320         svm->nested.ctl.int_ctl        |= svm->vmcb->control.int_ctl & mask;
 321 }
 322
 323 /*
 324  * Transfer any event that L0 or L1 wanted to inject into L2 to
 325  * EXIT_INT_INFO.
 326  */
 327 static void nested_vmcb_save_pending_event(struct vcpu_svm *svm,
 328                                            struct vmcb *vmcb12)
 329 {
 330         struct kvm_vcpu *vcpu = &svm->vcpu;
 331         u32 exit_int_info = 0;
 332         unsigned int nr;
 333
 334         if (vcpu->arch.exception.injected) {
 335                 nr = vcpu->arch.exception.nr;
 336                 exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT;
 337
 338                 if (vcpu->arch.exception.has_error_code) {
 339                         exit_int_info |= SVM_EVTINJ_VALID_ERR;
 340                         vmcb12->control.exit_int_info_err =
 341                                 vcpu->arch.exception.error_code;
 342                 }
 343
 344         } else if (vcpu->arch.nmi_injected) {
 345                 exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI;
 346
 347         } else if (vcpu->arch.interrupt.injected) {
 348                 nr = vcpu->arch.interrupt.nr;
 349                 exit_int_info = nr | SVM_EVTINJ_VALID;
 350
 351                 if (vcpu->arch.interrupt.soft)
 352                         exit_int_info |= SVM_EVTINJ_TYPE_SOFT;
 353                 else
 354                         exit_int_info |= SVM_EVTINJ_TYPE_INTR;
 355         }
 356
 357         vmcb12->control.exit_int_info = exit_int_info;
 358 }
 359
 360 static inline bool nested_npt_enabled(struct vcpu_svm *svm)
 361 {
 362         return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE;
 363 }
 364
 365 /*
 366  * Load guest's/host's cr3 on nested vmentry or vmexit. @nested_npt is true
 367  * if we are emulating VM-Entry into a guest with NPT enabled.
 368  */
 369 static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
 370                                bool nested_npt)
 371 {
 372         if (kvm_vcpu_is_illegal_gpa(vcpu, cr3))
 373                 return -EINVAL;
 374
 375         if (!nested_npt && is_pae_paging(vcpu) &&
 376             (cr3 != kvm_read_cr3(vcpu) || pdptrs_changed(vcpu))) {
 377                 if (!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3))
 378                         return -EINVAL;
 379         }
 380
 381         /*
 382          * TODO: optimize unconditional TLB flush/MMU sync here and in
 383          * kvm_init_shadow_npt_mmu().
 384          */
 385         if (!nested_npt)
 386                 kvm_mmu_new_pgd(vcpu, cr3, false, false);
 387
 388         vcpu->arch.cr3 = cr3;
 389         kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
 390
 391         kvm_init_mmu(vcpu, false);
 392
 393         return 0;
 394 }
 395
 396 static void nested_prepare_vmcb_save(struct vcpu_svm *svm, struct vmcb *vmcb12)
 397 {
 398         /* Load the nested guest state */
 399         svm->vmcb->save.es = vmcb12->save.es;
 400         svm->vmcb->save.cs = vmcb12->save.cs;
 401         svm->vmcb->save.ss = vmcb12->save.ss;
 402         svm->vmcb->save.ds = vmcb12->save.ds;
 403         svm->vmcb->save.gdtr = vmcb12->save.gdtr;
 404         svm->vmcb->save.idtr = vmcb12->save.idtr;
 405         kvm_set_rflags(&svm->vcpu, vmcb12->save.rflags | X86_EFLAGS_FIXED);
 406
 407         /*
 408          * Force-set EFER_SVME even though it is checked earlier on the
 409          * VMCB12, because the guest can flip the bit between the check
 410          * and now.  Clearing EFER_SVME would call svm_free_nested.
 411          */
 412         svm_set_efer(&svm->vcpu, vmcb12->save.efer | EFER_SVME);
 413
 414         svm_set_cr0(&svm->vcpu, vmcb12->save.cr0);
 415         svm_set_cr4(&svm->vcpu, vmcb12->save.cr4);
 416         svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = vmcb12->save.cr2;
 417         kvm_rax_write(&svm->vcpu, vmcb12->save.rax);
 418         kvm_rsp_write(&svm->vcpu, vmcb12->save.rsp);
 419         kvm_rip_write(&svm->vcpu, vmcb12->save.rip);
 420
 421         /* In case we don't even reach vcpu_run, the fields are not updated */
 422         svm->vmcb->save.rax = vmcb12->save.rax;
 423         svm->vmcb->save.rsp = vmcb12->save.rsp;
 424         svm->vmcb->save.rip = vmcb12->save.rip;
 425         svm->vmcb->save.dr7 = vmcb12->save.dr7 | DR7_FIXED_1;
 426         svm->vcpu.arch.dr6  = vmcb12->save.dr6 | DR6_ACTIVE_LOW;
 427         svm->vmcb->save.cpl = vmcb12->save.cpl;
 428 }
 429
 430 static void nested_prepare_vmcb_control(struct vcpu_svm *svm)
 431 {
 432         const u32 mask = V_INTR_MASKING_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK;
 433
 434         if (nested_npt_enabled(svm))
 435                 nested_svm_init_mmu_context(&svm->vcpu);
 436
 437         svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset =
 438                 svm->vcpu.arch.l1_tsc_offset + svm->nested.ctl.tsc_offset;
 439
 440         svm->vmcb->control.int_ctl             =
 441                 (svm->nested.ctl.int_ctl & ~mask) |
 442                 (svm->nested.hsave->control.int_ctl & mask);
 443
 444         svm->vmcb->control.virt_ext            = svm->nested.ctl.virt_ext;
 445         svm->vmcb->control.int_vector          = svm->nested.ctl.int_vector;
 446         svm->vmcb->control.int_state           = svm->nested.ctl.int_state;
 447         svm->vmcb->control.event_inj           = svm->nested.ctl.event_inj;
 448         svm->vmcb->control.event_inj_err       = svm->nested.ctl.event_inj_err;
 449
 450         svm->vmcb->control.pause_filter_count  = svm->nested.ctl.pause_filter_count;
 451         svm->vmcb->control.pause_filter_thresh = svm->nested.ctl.pause_filter_thresh;
 452
 453         /* Enter Guest-Mode */
 454         enter_guest_mode(&svm->vcpu);
 455
 456         /*
 457          * Merge guest and host intercepts - must be called  with vcpu in
 458          * guest-mode to take affect here
 459          */
 460         recalc_intercepts(svm);
 461
 462         vmcb_mark_all_dirty(svm->vmcb);
 463 }
 464
 465 int enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb12_gpa,
 466                          struct vmcb *vmcb12)
 467 {
 468         int ret;
 469
 470         trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb12_gpa,
 471                                vmcb12->save.rip,
 472                                vmcb12->control.int_ctl,
 473                                vmcb12->control.event_inj,
 474                                vmcb12->control.nested_ctl);
 475
 476         trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff,
 477                                     vmcb12->control.intercepts[INTERCEPT_CR] >> 16,
 478                                     vmcb12->control.intercepts[INTERCEPT_EXCEPTION],
 479                                     vmcb12->control.intercepts[INTERCEPT_WORD3],
 480                                     vmcb12->control.intercepts[INTERCEPT_WORD4],
 481                                     vmcb12->control.intercepts[INTERCEPT_WORD5]);
 482
 483
 484         svm->nested.vmcb12_gpa = vmcb12_gpa;
 485         nested_prepare_vmcb_control(svm);
 486         nested_prepare_vmcb_save(svm, vmcb12);
 487
 488         ret = nested_svm_load_cr3(&svm->vcpu, vmcb12->save.cr3,
 489                                   nested_npt_enabled(svm));
 490         if (ret)
 491                 return ret;
 492
 493         if (!npt_enabled)
 494                 svm->vcpu.arch.mmu->inject_page_fault = svm_inject_page_fault_nested;
 495
 496         svm_set_gif(svm, true);
 497
 498         return 0;
 499 }
 500
 501 int nested_svm_vmrun(struct vcpu_svm *svm)
 502 {
 503         int ret;
 504         struct vmcb *vmcb12;
 505         struct vmcb *hsave = svm->nested.hsave;
 506         struct vmcb *vmcb = svm->vmcb;
 507         struct kvm_host_map map;
 508         u64 vmcb12_gpa;
 509
 510         if (is_smm(&svm->vcpu)) {
 511                 kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 512                 return 1;
 513         }
 514
 515         vmcb12_gpa = svm->vmcb->save.rax;
 516         ret = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb12_gpa), &map);
 517         if (ret == -EINVAL) {
 518                 kvm_inject_gp(&svm->vcpu, 0);
 519                 return 1;
 520         } else if (ret) {
 521                 return kvm_skip_emulated_instruction(&svm->vcpu);
 522         }
 523
 524         ret = kvm_skip_emulated_instruction(&svm->vcpu);
 525
 526         vmcb12 = map.hva;
 527
 528         if (WARN_ON_ONCE(!svm->nested.initialized))
 529                 return -EINVAL;
 530
 531         load_nested_vmcb_control(svm, &vmcb12->control);
 532
 533         if (!nested_vmcb_check_save(svm, vmcb12) ||
 534             !nested_vmcb_check_controls(&svm->nested.ctl)) {
 535                 vmcb12->control.exit_code    = SVM_EXIT_ERR;
 536                 vmcb12->control.exit_code_hi = 0;
 537                 vmcb12->control.exit_info_1  = 0;
 538                 vmcb12->control.exit_info_2  = 0;
 539                 goto out;
 540         }
 541
 542
 543         /* Clear internal status */
 544         kvm_clear_exception_queue(&svm->vcpu);
 545         kvm_clear_interrupt_queue(&svm->vcpu);
 546
 547         /*
 548          * Save the old vmcb, so we don't need to pick what we save, but can
 549          * restore everything when a VMEXIT occurs
 550          */
 551         hsave->save.es     = vmcb->save.es;
 552         hsave->save.cs     = vmcb->save.cs;
 553         hsave->save.ss     = vmcb->save.ss;
 554         hsave->save.ds     = vmcb->save.ds;
 555         hsave->save.gdtr   = vmcb->save.gdtr;
 556         hsave->save.idtr   = vmcb->save.idtr;
 557         hsave->save.efer   = svm->vcpu.arch.efer;
 558         hsave->save.cr0    = kvm_read_cr0(&svm->vcpu);
 559         hsave->save.cr4    = svm->vcpu.arch.cr4;
 560         hsave->save.rflags = kvm_get_rflags(&svm->vcpu);
 561         hsave->save.rip    = kvm_rip_read(&svm->vcpu);
 562         hsave->save.rsp    = vmcb->save.rsp;
 563         hsave->save.rax    = vmcb->save.rax;
 564         if (npt_enabled)
 565                 hsave->save.cr3    = vmcb->save.cr3;
 566         else
 567                 hsave->save.cr3    = kvm_read_cr3(&svm->vcpu);
 568
 569         copy_vmcb_control_area(&hsave->control, &vmcb->control);
 570
 571         svm->nested.nested_run_pending = 1;
 572
 573         if (enter_svm_guest_mode(svm, vmcb12_gpa, vmcb12))
 574                 goto out_exit_err;
 575
 576         if (nested_svm_vmrun_msrpm(svm))
 577                 goto out;
 578
 579 out_exit_err:
 580         svm->nested.nested_run_pending = 0;
 581
 582         svm->vmcb->control.exit_code    = SVM_EXIT_ERR;
 583         svm->vmcb->control.exit_code_hi = 0;
 584         svm->vmcb->control.exit_info_1  = 0;
 585         svm->vmcb->control.exit_info_2  = 0;
 586
 587         nested_svm_vmexit(svm);
 588
 589 out:
 590         kvm_vcpu_unmap(&svm->vcpu, &map, true);
 591
 592         return ret;
 593 }
 594
 595 void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
 596 {
 597         to_vmcb->save.fs = from_vmcb->save.fs;
 598         to_vmcb->save.gs = from_vmcb->save.gs;
 599         to_vmcb->save.tr = from_vmcb->save.tr;
 600         to_vmcb->save.ldtr = from_vmcb->save.ldtr;
 601         to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
 602         to_vmcb->save.star = from_vmcb->save.star;
 603         to_vmcb->save.lstar = from_vmcb->save.lstar;
 604         to_vmcb->save.cstar = from_vmcb->save.cstar;
 605         to_vmcb->save.sfmask = from_vmcb->save.sfmask;
 606         to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
 607         to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
 608         to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
 609 }
 610
 611 int nested_svm_vmexit(struct vcpu_svm *svm)
 612 {
 613         int rc;
 614         struct vmcb *vmcb12;
 615         struct vmcb *hsave = svm->nested.hsave;
 616         struct vmcb *vmcb = svm->vmcb;
 617         struct kvm_host_map map;
 618
 619         rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map);
 620         if (rc) {
 621                 if (rc == -EINVAL)
 622                         kvm_inject_gp(&svm->vcpu, 0);
 623                 return 1;
 624         }
 625
 626         vmcb12 = map.hva;
 627
 628         /* Exit Guest-Mode */
 629         leave_guest_mode(&svm->vcpu);
 630         svm->nested.vmcb12_gpa = 0;
 631         WARN_ON_ONCE(svm->nested.nested_run_pending);
 632
 633         kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->vcpu);
 634
 635         /* in case we halted in L2 */
 636         svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE;
 637
 638         /* Give the current vmcb to the guest */
 639
 640         vmcb12->save.es     = vmcb->save.es;
 641         vmcb12->save.cs     = vmcb->save.cs;
 642         vmcb12->save.ss     = vmcb->save.ss;
 643         vmcb12->save.ds     = vmcb->save.ds;
 644         vmcb12->save.gdtr   = vmcb->save.gdtr;
 645         vmcb12->save.idtr   = vmcb->save.idtr;
 646         vmcb12->save.efer   = svm->vcpu.arch.efer;
 647         vmcb12->save.cr0    = kvm_read_cr0(&svm->vcpu);
 648         vmcb12->save.cr3    = kvm_read_cr3(&svm->vcpu);
 649         vmcb12->save.cr2    = vmcb->save.cr2;
 650         vmcb12->save.cr4    = svm->vcpu.arch.cr4;
 651         vmcb12->save.rflags = kvm_get_rflags(&svm->vcpu);
 652         vmcb12->save.rip    = kvm_rip_read(&svm->vcpu);
 653         vmcb12->save.rsp    = kvm_rsp_read(&svm->vcpu);
 654         vmcb12->save.rax    = kvm_rax_read(&svm->vcpu);
 655         vmcb12->save.dr7    = vmcb->save.dr7;
 656         vmcb12->save.dr6    = svm->vcpu.arch.dr6;
 657         vmcb12->save.cpl    = vmcb->save.cpl;
 658
 659         vmcb12->control.int_state         = vmcb->control.int_state;
 660         vmcb12->control.exit_code         = vmcb->control.exit_code;
 661         vmcb12->control.exit_code_hi      = vmcb->control.exit_code_hi;
 662         vmcb12->control.exit_info_1       = vmcb->control.exit_info_1;
 663         vmcb12->control.exit_info_2       = vmcb->control.exit_info_2;
 664
 665         if (vmcb12->control.exit_code != SVM_EXIT_ERR)
 666                 nested_vmcb_save_pending_event(svm, vmcb12);
 667
 668         if (svm->nrips_enabled)
 669                 vmcb12->control.next_rip  = vmcb->control.next_rip;
 670
 671         vmcb12->control.int_ctl           = svm->nested.ctl.int_ctl;
 672         vmcb12->control.tlb_ctl           = svm->nested.ctl.tlb_ctl;
 673         vmcb12->control.event_inj         = svm->nested.ctl.event_inj;
 674         vmcb12->control.event_inj_err     = svm->nested.ctl.event_inj_err;
 675
 676         vmcb12->control.pause_filter_count =
 677                 svm->vmcb->control.pause_filter_count;
 678         vmcb12->control.pause_filter_thresh =
 679                 svm->vmcb->control.pause_filter_thresh;
 680
 681         /* Restore the original control entries */
 682         copy_vmcb_control_area(&vmcb->control, &hsave->control);
 683
 684         /* On vmexit the  GIF is set to false */
 685         svm_set_gif(svm, false);
 686
 687         svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset =
 688                 svm->vcpu.arch.l1_tsc_offset;
 689
 690         svm->nested.ctl.nested_cr3 = 0;
 691
 692         /* Restore selected save entries */
 693         svm->vmcb->save.es = hsave->save.es;
 694         svm->vmcb->save.cs = hsave->save.cs;
 695         svm->vmcb->save.ss = hsave->save.ss;
 696         svm->vmcb->save.ds = hsave->save.ds;
 697         svm->vmcb->save.gdtr = hsave->save.gdtr;
 698         svm->vmcb->save.idtr = hsave->save.idtr;
 699         kvm_set_rflags(&svm->vcpu, hsave->save.rflags);
 700         kvm_set_rflags(&svm->vcpu, hsave->save.rflags | X86_EFLAGS_FIXED);
 701         svm_set_efer(&svm->vcpu, hsave->save.efer);
 702         svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE);
 703         svm_set_cr4(&svm->vcpu, hsave->save.cr4);
 704         kvm_rax_write(&svm->vcpu, hsave->save.rax);
 705         kvm_rsp_write(&svm->vcpu, hsave->save.rsp);
 706         kvm_rip_write(&svm->vcpu, hsave->save.rip);
 707         svm->vmcb->save.dr7 = DR7_FIXED_1;
 708         svm->vmcb->save.cpl = 0;
 709         svm->vmcb->control.exit_int_info = 0;
 710
 711         vmcb_mark_all_dirty(svm->vmcb);
 712
 713         trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code,
 714                                        vmcb12->control.exit_info_1,
 715                                        vmcb12->control.exit_info_2,
 716                                        vmcb12->control.exit_int_info,
 717                                        vmcb12->control.exit_int_info_err,
 718                                        KVM_ISA_SVM);
 719
 720         kvm_vcpu_unmap(&svm->vcpu, &map, true);
 721
 722         nested_svm_uninit_mmu_context(&svm->vcpu);
 723
 724         rc = nested_svm_load_cr3(&svm->vcpu, hsave->save.cr3, false);
 725         if (rc)
 726                 return 1;
 727
 728         if (npt_enabled)
 729                 svm->vmcb->save.cr3 = hsave->save.cr3;
 730
 731         /*
 732          * Drop what we picked up for L2 via svm_complete_interrupts() so it
 733          * doesn't end up in L1.
 734          */
 735         svm->vcpu.arch.nmi_injected = false;
 736         kvm_clear_exception_queue(&svm->vcpu);
 737         kvm_clear_interrupt_queue(&svm->vcpu);
 738
 739         return 0;
 740 }
 741
 742 int svm_allocate_nested(struct vcpu_svm *svm)
 743 {
 744         struct page *hsave_page;
 745
 746         if (svm->nested.initialized)
 747                 return 0;
 748
 749         hsave_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
 750         if (!hsave_page)
 751                 return -ENOMEM;
 752         svm->nested.hsave = page_address(hsave_page);
 753
 754         svm->nested.msrpm = svm_vcpu_alloc_msrpm();
 755         if (!svm->nested.msrpm)
 756                 goto err_free_hsave;
 757         svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm);
 758
 759         svm->nested.initialized = true;
 760         return 0;
 761
 762 err_free_hsave:
 763         __free_page(hsave_page);
 764         return -ENOMEM;
 765 }
 766
 767 void svm_free_nested(struct vcpu_svm *svm)
 768 {
 769         if (!svm->nested.initialized)
 770                 return;
 771
 772         svm_vcpu_free_msrpm(svm->nested.msrpm);
 773         svm->nested.msrpm = NULL;
 774
 775         __free_page(virt_to_page(svm->nested.hsave));
 776         svm->nested.hsave = NULL;
 777
 778         svm->nested.initialized = false;
 779 }
 780
 781 /*
 782  * Forcibly leave nested mode in order to be able to reset the VCPU later on.
 783  */
 784 void svm_leave_nested(struct vcpu_svm *svm)
 785 {
 786         if (is_guest_mode(&svm->vcpu)) {
 787                 struct vmcb *hsave = svm->nested.hsave;
 788                 struct vmcb *vmcb = svm->vmcb;
 789
 790                 svm->nested.nested_run_pending = 0;
 791                 leave_guest_mode(&svm->vcpu);
 792                 copy_vmcb_control_area(&vmcb->control, &hsave->control);
 793                 nested_svm_uninit_mmu_context(&svm->vcpu);
 794                 vmcb_mark_all_dirty(svm->vmcb);
 795         }
 796
 797         kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->vcpu);
 798 }
 799
 800 static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
 801 {
 802         u32 offset, msr, value;
 803         int write, mask;
 804
 805         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
 806                 return NESTED_EXIT_HOST;
 807
 808         msr    = svm->vcpu.arch.regs[VCPU_REGS_RCX];
 809         offset = svm_msrpm_offset(msr);
 810         write  = svm->vmcb->control.exit_info_1 & 1;
 811         mask   = 1 << ((2 * (msr & 0xf)) + write);
 812
 813         if (offset == MSR_INVALID)
 814                 return NESTED_EXIT_DONE;
 815
 816         /* Offset is in 32 bit units but need in 8 bit units */
 817         offset *= 4;
 818
 819         if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4))
 820                 return NESTED_EXIT_DONE;
 821
 822         return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
 823 }
 824
 825 static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
 826 {
 827         unsigned port, size, iopm_len;
 828         u16 val, mask;
 829         u8 start_bit;
 830         u64 gpa;
 831
 832         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
 833                 return NESTED_EXIT_HOST;
 834
 835         port = svm->vmcb->control.exit_info_1 >> 16;
 836         size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >>
 837                 SVM_IOIO_SIZE_SHIFT;
 838         gpa  = svm->nested.ctl.iopm_base_pa + (port / 8);
 839         start_bit = port % 8;
 840         iopm_len = (start_bit + size > 8) ? 2 : 1;
 841         mask = (0xf >> (4 - size)) << start_bit;
 842         val = 0;
 843
 844         if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len))
 845                 return NESTED_EXIT_DONE;
 846
 847         return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
 848 }
 849
 850 static int nested_svm_intercept(struct vcpu_svm *svm)
 851 {
 852         u32 exit_code = svm->vmcb->control.exit_code;
 853         int vmexit = NESTED_EXIT_HOST;
 854
 855         switch (exit_code) {
 856         case SVM_EXIT_MSR:
 857                 vmexit = nested_svm_exit_handled_msr(svm);
 858                 break;
 859         case SVM_EXIT_IOIO:
 860                 vmexit = nested_svm_intercept_ioio(svm);
 861                 break;
 862         case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
 863                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 864                         vmexit = NESTED_EXIT_DONE;
 865                 break;
 866         }
 867         case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
 868                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 869                         vmexit = NESTED_EXIT_DONE;
 870                 break;
 871         }
 872         case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
 873                 /*
 874                  * Host-intercepted exceptions have been checked already in
 875                  * nested_svm_exit_special.  There is nothing to do here,
 876                  * the vmexit is injected by svm_check_nested_events.
 877                  */
 878                 vmexit = NESTED_EXIT_DONE;
 879                 break;
 880         }
 881         case SVM_EXIT_ERR: {
 882                 vmexit = NESTED_EXIT_DONE;
 883                 break;
 884         }
 885         default: {
 886                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 887                         vmexit = NESTED_EXIT_DONE;
 888         }
 889         }
 890
 891         return vmexit;
 892 }
 893
 894 int nested_svm_exit_handled(struct vcpu_svm *svm)
 895 {
 896         int vmexit;
 897
 898         vmexit = nested_svm_intercept(svm);
 899
 900         if (vmexit == NESTED_EXIT_DONE)
 901                 nested_svm_vmexit(svm);
 902
 903         return vmexit;
 904 }
 905
 906 int nested_svm_check_permissions(struct vcpu_svm *svm)
 907 {
 908         if (!(svm->vcpu.arch.efer & EFER_SVME) ||
 909             !is_paging(&svm->vcpu)) {
 910                 kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 911                 return 1;
 912         }
 913
 914         if (svm->vmcb->save.cpl) {
 915                 kvm_inject_gp(&svm->vcpu, 0);
 916                 return 1;
 917         }
 918
 919         return 0;
 920 }
 921
 922 static bool nested_exit_on_exception(struct vcpu_svm *svm)
 923 {
 924         unsigned int nr = svm->vcpu.arch.exception.nr;
 925
 926         return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(nr));
 927 }
 928
 929 static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm)
 930 {
 931         unsigned int nr = svm->vcpu.arch.exception.nr;
 932
 933         svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
 934         svm->vmcb->control.exit_code_hi = 0;
 935
 936         if (svm->vcpu.arch.exception.has_error_code)
 937                 svm->vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code;
 938
 939         /*
 940          * EXITINFO2 is undefined for all exception intercepts other
 941          * than #PF.
 942          */
 943         if (nr == PF_VECTOR) {
 944                 if (svm->vcpu.arch.exception.nested_apf)
 945                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token;
 946                 else if (svm->vcpu.arch.exception.has_payload)
 947                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload;
 948                 else
 949                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2;
 950         } else if (nr == DB_VECTOR) {
 951                 /* See inject_pending_event.  */
 952                 kvm_deliver_exception_payload(&svm->vcpu);
 953                 if (svm->vcpu.arch.dr7 & DR7_GD) {
 954                         svm->vcpu.arch.dr7 &= ~DR7_GD;
 955                         kvm_update_dr7(&svm->vcpu);
 956                 }
 957         } else
 958                 WARN_ON(svm->vcpu.arch.exception.has_payload);
 959
 960         nested_svm_vmexit(svm);
 961 }
 962
 963 static void nested_svm_smi(struct vcpu_svm *svm)
 964 {
 965         svm->vmcb->control.exit_code = SVM_EXIT_SMI;
 966         svm->vmcb->control.exit_info_1 = 0;
 967         svm->vmcb->control.exit_info_2 = 0;
 968
 969         nested_svm_vmexit(svm);
 970 }
 971
 972 static void nested_svm_nmi(struct vcpu_svm *svm)
 973 {
 974         svm->vmcb->control.exit_code = SVM_EXIT_NMI;
 975         svm->vmcb->control.exit_info_1 = 0;
 976         svm->vmcb->control.exit_info_2 = 0;
 977
 978         nested_svm_vmexit(svm);
 979 }
 980
 981 static void nested_svm_intr(struct vcpu_svm *svm)
 982 {
 983         trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
 984
 985         svm->vmcb->control.exit_code   = SVM_EXIT_INTR;
 986         svm->vmcb->control.exit_info_1 = 0;
 987         svm->vmcb->control.exit_info_2 = 0;
 988
 989         nested_svm_vmexit(svm);
 990 }
 991
 992 static inline bool nested_exit_on_init(struct vcpu_svm *svm)
 993 {
 994         return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
 995 }
 996
 997 static void nested_svm_init(struct vcpu_svm *svm)
 998 {
 999         svm->vmcb->control.exit_code   = SVM_EXIT_INIT;
1000         svm->vmcb->control.exit_info_1 = 0;
1001         svm->vmcb->control.exit_info_2 = 0;
1002
1003         nested_svm_vmexit(svm);
1004 }
1005
1006
1007 static int svm_check_nested_events(struct kvm_vcpu *vcpu)
1008 {
1009         struct vcpu_svm *svm = to_svm(vcpu);
1010         bool block_nested_events =
1011                 kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending;
1012         struct kvm_lapic *apic = vcpu->arch.apic;
1013
1014         if (lapic_in_kernel(vcpu) &&
1015             test_bit(KVM_APIC_INIT, &apic->pending_events)) {
1016                 if (block_nested_events)
1017                         return -EBUSY;
1018                 if (!nested_exit_on_init(svm))
1019                         return 0;
1020                 nested_svm_init(svm);
1021                 return 0;
1022         }
1023
1024         if (vcpu->arch.exception.pending) {
1025                 if (block_nested_events)
1026                         return -EBUSY;
1027                 if (!nested_exit_on_exception(svm))
1028                         return 0;
1029                 nested_svm_inject_exception_vmexit(svm);
1030                 return 0;
1031         }
1032
1033         if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
1034                 if (block_nested_events)
1035                         return -EBUSY;
1036                 if (!nested_exit_on_smi(svm))
1037                         return 0;
1038                 nested_svm_smi(svm);
1039                 return 0;
1040         }
1041
1042         if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
1043                 if (block_nested_events)
1044                         return -EBUSY;
1045                 if (!nested_exit_on_nmi(svm))
1046                         return 0;
1047                 nested_svm_nmi(svm);
1048                 return 0;
1049         }
1050
1051         if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
1052                 if (block_nested_events)
1053                         return -EBUSY;
1054                 if (!nested_exit_on_intr(svm))
1055                         return 0;
1056                 nested_svm_intr(svm);
1057                 return 0;
1058         }
1059
1060         return 0;
1061 }
1062
1063 int nested_svm_exit_special(struct vcpu_svm *svm)
1064 {
1065         u32 exit_code = svm->vmcb->control.exit_code;
1066
1067         switch (exit_code) {
1068         case SVM_EXIT_INTR:
1069         case SVM_EXIT_NMI:
1070         case SVM_EXIT_NPF:
1071                 return NESTED_EXIT_HOST;
1072         case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1073                 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
1074
1075                 if (get_host_vmcb(svm)->control.intercepts[INTERCEPT_EXCEPTION] &
1076                                 excp_bits)
1077                         return NESTED_EXIT_HOST;
1078                 else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR &&
1079                          svm->vcpu.arch.apf.host_apf_flags)
1080                         /* Trap async PF even if not shadowing */
1081                         return NESTED_EXIT_HOST;
1082                 break;
1083         }
1084         default:
1085                 break;
1086         }
1087
1088         return NESTED_EXIT_CONTINUE;
1089 }
1090
1091 static int svm_get_nested_state(struct kvm_vcpu *vcpu,
1092                                 struct kvm_nested_state __user *user_kvm_nested_state,
1093                                 u32 user_data_size)
1094 {
1095         struct vcpu_svm *svm;
1096         struct kvm_nested_state kvm_state = {
1097                 .flags = 0,
1098                 .format = KVM_STATE_NESTED_FORMAT_SVM,
1099                 .size = sizeof(kvm_state),
1100         };
1101         struct vmcb __user *user_vmcb = (struct vmcb __user *)
1102                 &user_kvm_nested_state->data.svm[0];
1103
1104         if (!vcpu)
1105                 return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE;
1106
1107         svm = to_svm(vcpu);
1108
1109         if (user_data_size < kvm_state.size)
1110                 goto out;
1111
1112         /* First fill in the header and copy it out.  */
1113         if (is_guest_mode(vcpu)) {
1114                 kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa;
1115                 kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
1116                 kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
1117
1118                 if (svm->nested.nested_run_pending)
1119                         kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING;
1120         }
1121
1122         if (gif_set(svm))
1123                 kvm_state.flags |= KVM_STATE_NESTED_GIF_SET;
1124
1125         if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state)))
1126                 return -EFAULT;
1127
1128         if (!is_guest_mode(vcpu))
1129                 goto out;
1130
1131         /*
1132          * Copy over the full size of the VMCB rather than just the size
1133          * of the structs.
1134          */
1135         if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
1136                 return -EFAULT;
1137         if (copy_to_user(&user_vmcb->control, &svm->nested.ctl,
1138                          sizeof(user_vmcb->control)))
1139                 return -EFAULT;
1140         if (copy_to_user(&user_vmcb->save, &svm->nested.hsave->save,
1141                          sizeof(user_vmcb->save)))
1142                 return -EFAULT;
1143
1144 out:
1145         return kvm_state.size;
1146 }
1147
1148 static int svm_set_nested_state(struct kvm_vcpu *vcpu,
1149                                 struct kvm_nested_state __user *user_kvm_nested_state,
1150                                 struct kvm_nested_state *kvm_state)
1151 {
1152         struct vcpu_svm *svm = to_svm(vcpu);
1153         struct vmcb *hsave = svm->nested.hsave;
1154         struct vmcb __user *user_vmcb = (struct vmcb __user *)
1155                 &user_kvm_nested_state->data.svm[0];
1156         struct vmcb_control_area *ctl;
1157         struct vmcb_save_area *save;
1158         int ret;
1159         u32 cr0;
1160
1161         BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
1162                      KVM_STATE_NESTED_SVM_VMCB_SIZE);
1163
1164         if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
1165                 return -EINVAL;
1166
1167         if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE |
1168                                  KVM_STATE_NESTED_RUN_PENDING |
1169                                  KVM_STATE_NESTED_GIF_SET))
1170                 return -EINVAL;
1171
1172         /*
1173          * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's
1174          * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed.
1175          */
1176         if (!(vcpu->arch.efer & EFER_SVME)) {
1177                 /* GIF=1 and no guest mode are required if SVME=0.  */
1178                 if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET)
1179                         return -EINVAL;
1180         }
1181
1182         /* SMM temporarily disables SVM, so we cannot be in guest mode.  */
1183         if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE))
1184                 return -EINVAL;
1185
1186         if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
1187                 svm_leave_nested(svm);
1188                 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1189                 return 0;
1190         }
1191
1192         if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
1193                 return -EINVAL;
1194         if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE)
1195                 return -EINVAL;
1196
1197         ret  = -ENOMEM;
1198         ctl  = kzalloc(sizeof(*ctl),  GFP_KERNEL);
1199         save = kzalloc(sizeof(*save), GFP_KERNEL);
1200         if (!ctl || !save)
1201                 goto out_free;
1202
1203         ret = -EFAULT;
1204         if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl)))
1205                 goto out_free;
1206         if (copy_from_user(save, &user_vmcb->save, sizeof(*save)))
1207                 goto out_free;
1208
1209         ret = -EINVAL;
1210         if (!nested_vmcb_check_controls(ctl))
1211                 goto out_free;
1212
1213         /*
1214          * Processor state contains L2 state.  Check that it is
1215          * valid for guest mode (see nested_vmcb_checks).
1216          */
1217         cr0 = kvm_read_cr0(vcpu);
1218         if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
1219                 goto out_free;
1220
1221         /*
1222          * Validate host state saved from before VMRUN (see
1223          * nested_svm_check_permissions).
1224          * TODO: validate reserved bits for all saved state.
1225          */
1226         if (!(save->cr0 & X86_CR0_PG))
1227                 goto out_free;
1228         if (!(save->efer & EFER_SVME))
1229                 goto out_free;
1230
1231         /*
1232          * All checks done, we can enter guest mode.  L1 control fields
1233          * come from the nested save state.  Guest state is already
1234          * in the registers, the save area of the nested state instead
1235          * contains saved L1 state.
1236          */
1237
1238         svm->nested.nested_run_pending =
1239                 !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);
1240
1241         copy_vmcb_control_area(&hsave->control, &svm->vmcb->control);
1242         hsave->save = *save;
1243
1244         svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;
1245         load_nested_vmcb_control(svm, ctl);
1246         nested_prepare_vmcb_control(svm);
1247
1248         kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1249         ret = 0;
1250 out_free:
1251         kfree(save);
1252         kfree(ctl);
1253
1254         return ret;
1255 }
1256
1257 struct kvm_x86_nested_ops svm_nested_ops = {
1258         .check_events = svm_check_nested_events,
1259         .get_nested_state_pages = svm_get_nested_state_pages,
1260         .get_state = svm_get_nested_state,
1261         .set_state = svm_set_nested_state,
1262 };