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 u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index)
  55 {
  56         struct vcpu_svm *svm = to_svm(vcpu);
  57         u64 cr3 = svm->nested.ctl.nested_cr3;
  58         u64 pdpte;
  59         int ret;
  60
  61         ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(__sme_clr(cr3)), &pdpte,
  62                                        offset_in_page(cr3) + index * 8, 8);
  63         if (ret)
  64                 return 0;
  65         return pdpte;
  66 }
  67
  68 static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu)
  69 {
  70         struct vcpu_svm *svm = to_svm(vcpu);
  71
  72         return svm->nested.ctl.nested_cr3;
  73 }
  74
  75 static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
  76 {
  77         struct vcpu_svm *svm = to_svm(vcpu);
  78         struct vmcb *hsave = svm->nested.hsave;
  79
  80         WARN_ON(mmu_is_nested(vcpu));
  81
  82         vcpu->arch.mmu = &vcpu->arch.guest_mmu;
  83         kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, hsave->save.cr4, hsave->save.efer,
  84                                 svm->nested.ctl.nested_cr3);
  85         vcpu->arch.mmu->get_guest_pgd     = nested_svm_get_tdp_cr3;
  86         vcpu->arch.mmu->get_pdptr         = nested_svm_get_tdp_pdptr;
  87         vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit;
  88         reset_shadow_zero_bits_mask(vcpu, vcpu->arch.mmu);
  89         vcpu->arch.walk_mmu              = &vcpu->arch.nested_mmu;
  90 }
  91
  92 static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)
  93 {
  94         vcpu->arch.mmu = &vcpu->arch.root_mmu;
  95         vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;
  96 }
  97
  98 void recalc_intercepts(struct vcpu_svm *svm)
  99 {
 100         struct vmcb_control_area *c, *h, *g;
 101         unsigned int i;
 102
 103         vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
 104
 105         if (!is_guest_mode(&svm->vcpu))
 106                 return;
 107
 108         c = &svm->vmcb->control;
 109         h = &svm->nested.hsave->control;
 110         g = &svm->nested.ctl;
 111
 112         for (i = 0; i < MAX_INTERCEPT; i++)
 113                 c->intercepts[i] = h->intercepts[i];
 114
 115         if (g->int_ctl & V_INTR_MASKING_MASK) {
 116                 /* We only want the cr8 intercept bits of L1 */
 117                 vmcb_clr_intercept(c, INTERCEPT_CR8_READ);
 118                 vmcb_clr_intercept(c, INTERCEPT_CR8_WRITE);
 119
 120                 /*
 121                  * Once running L2 with HF_VINTR_MASK, EFLAGS.IF does not
 122                  * affect any interrupt we may want to inject; therefore,
 123                  * interrupt window vmexits are irrelevant to L0.
 124                  */
 125                 vmcb_clr_intercept(c, INTERCEPT_VINTR);
 126         }
 127
 128         /* We don't want to see VMMCALLs from a nested guest */
 129         vmcb_clr_intercept(c, INTERCEPT_VMMCALL);
 130
 131         for (i = 0; i < MAX_INTERCEPT; i++)
 132                 c->intercepts[i] |= g->intercepts[i];
 133 }
 134
 135 static void copy_vmcb_control_area(struct vmcb_control_area *dst,
 136                                    struct vmcb_control_area *from)
 137 {
 138         unsigned int i;
 139
 140         for (i = 0; i < MAX_INTERCEPT; i++)
 141                 dst->intercepts[i] = from->intercepts[i];
 142
 143         dst->iopm_base_pa         = from->iopm_base_pa;
 144         dst->msrpm_base_pa        = from->msrpm_base_pa;
 145         dst->tsc_offset           = from->tsc_offset;
 146         /* asid not copied, it is handled manually for svm->vmcb.  */
 147         dst->tlb_ctl              = from->tlb_ctl;
 148         dst->int_ctl              = from->int_ctl;
 149         dst->int_vector           = from->int_vector;
 150         dst->int_state            = from->int_state;
 151         dst->exit_code            = from->exit_code;
 152         dst->exit_code_hi         = from->exit_code_hi;
 153         dst->exit_info_1          = from->exit_info_1;
 154         dst->exit_info_2          = from->exit_info_2;
 155         dst->exit_int_info        = from->exit_int_info;
 156         dst->exit_int_info_err    = from->exit_int_info_err;
 157         dst->nested_ctl           = from->nested_ctl;
 158         dst->event_inj            = from->event_inj;
 159         dst->event_inj_err        = from->event_inj_err;
 160         dst->nested_cr3           = from->nested_cr3;
 161         dst->virt_ext              = from->virt_ext;
 162         dst->pause_filter_count   = from->pause_filter_count;
 163         dst->pause_filter_thresh  = from->pause_filter_thresh;
 164 }
 165
 166 static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
 167 {
 168         /*
 169          * This function merges the msr permission bitmaps of kvm and the
 170          * nested vmcb. It is optimized in that it only merges the parts where
 171          * the kvm msr permission bitmap may contain zero bits
 172          */
 173         int i;
 174
 175         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
 176                 return true;
 177
 178         for (i = 0; i < MSRPM_OFFSETS; i++) {
 179                 u32 value, p;
 180                 u64 offset;
 181
 182                 if (msrpm_offsets[i] == 0xffffffff)
 183                         break;
 184
 185                 p      = msrpm_offsets[i];
 186                 offset = svm->nested.ctl.msrpm_base_pa + (p * 4);
 187
 188                 if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4))
 189                         return false;
 190
 191                 svm->nested.msrpm[p] = svm->msrpm[p] | value;
 192         }
 193
 194         svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm));
 195
 196         return true;
 197 }
 198
 199 static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
 200 {
 201         struct vcpu_svm *svm = to_svm(vcpu);
 202         if (!nested_svm_vmrun_msrpm(svm)) {
 203                 vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 204                 vcpu->run->internal.suberror =
 205                         KVM_INTERNAL_ERROR_EMULATION;
 206                 vcpu->run->internal.ndata = 0;
 207                 return false;
 208         }
 209
 210         return true;
 211 }
 212
 213 static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
 214 {
 215         if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0)
 216                 return false;
 217
 218         if (control->asid == 0)
 219                 return false;
 220
 221         if ((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) &&
 222             !npt_enabled)
 223                 return false;
 224
 225         return true;
 226 }
 227
 228 static bool nested_vmcb_checks(struct vcpu_svm *svm, struct vmcb *vmcb12)
 229 {
 230         bool vmcb12_lma;
 231
 232         if ((vmcb12->save.efer & EFER_SVME) == 0)
 233                 return false;
 234
 235         if (((vmcb12->save.cr0 & X86_CR0_CD) == 0) && (vmcb12->save.cr0 & X86_CR0_NW))
 236                 return false;
 237
 238         if (!kvm_dr6_valid(vmcb12->save.dr6) || !kvm_dr7_valid(vmcb12->save.dr7))
 239                 return false;
 240
 241         vmcb12_lma = (vmcb12->save.efer & EFER_LME) && (vmcb12->save.cr0 & X86_CR0_PG);
 242
 243         if (!vmcb12_lma) {
 244                 if (vmcb12->save.cr4 & X86_CR4_PAE) {
 245                         if (vmcb12->save.cr3 & MSR_CR3_LEGACY_PAE_RESERVED_MASK)
 246                                 return false;
 247                 } else {
 248                         if (vmcb12->save.cr3 & MSR_CR3_LEGACY_RESERVED_MASK)
 249                                 return false;
 250                 }
 251         } else {
 252                 if (!(vmcb12->save.cr4 & X86_CR4_PAE) ||
 253                     !(vmcb12->save.cr0 & X86_CR0_PE) ||
 254                     (vmcb12->save.cr3 & MSR_CR3_LONG_MBZ_MASK))
 255                         return false;
 256         }
 257         if (kvm_valid_cr4(&svm->vcpu, vmcb12->save.cr4))
 258                 return false;
 259
 260         return nested_vmcb_check_controls(&vmcb12->control);
 261 }
 262
 263 static void load_nested_vmcb_control(struct vcpu_svm *svm,
 264                                      struct vmcb_control_area *control)
 265 {
 266         copy_vmcb_control_area(&svm->nested.ctl, control);
 267
 268         /* Copy it here because nested_svm_check_controls will check it.  */
 269         svm->nested.ctl.asid           = control->asid;
 270         svm->nested.ctl.msrpm_base_pa &= ~0x0fffULL;
 271         svm->nested.ctl.iopm_base_pa  &= ~0x0fffULL;
 272 }
 273
 274 /*
 275  * Synchronize fields that are written by the processor, so that
 276  * they can be copied back into the nested_vmcb.
 277  */
 278 void sync_nested_vmcb_control(struct vcpu_svm *svm)
 279 {
 280         u32 mask;
 281         svm->nested.ctl.event_inj      = svm->vmcb->control.event_inj;
 282         svm->nested.ctl.event_inj_err  = svm->vmcb->control.event_inj_err;
 283
 284         /* Only a few fields of int_ctl are written by the processor.  */
 285         mask = V_IRQ_MASK | V_TPR_MASK;
 286         if (!(svm->nested.ctl.int_ctl & V_INTR_MASKING_MASK) &&
 287             svm_is_intercept(svm, INTERCEPT_VINTR)) {
 288                 /*
 289                  * In order to request an interrupt window, L0 is usurping
 290                  * svm->vmcb->control.int_ctl and possibly setting V_IRQ
 291                  * even if it was clear in L1's VMCB.  Restoring it would be
 292                  * wrong.  However, in this case V_IRQ will remain true until
 293                  * interrupt_window_interception calls svm_clear_vintr and
 294                  * restores int_ctl.  We can just leave it aside.
 295                  */
 296                 mask &= ~V_IRQ_MASK;
 297         }
 298         svm->nested.ctl.int_ctl        &= ~mask;
 299         svm->nested.ctl.int_ctl        |= svm->vmcb->control.int_ctl & mask;
 300 }
 301
 302 /*
 303  * Transfer any event that L0 or L1 wanted to inject into L2 to
 304  * EXIT_INT_INFO.
 305  */
 306 static void nested_vmcb_save_pending_event(struct vcpu_svm *svm,
 307                                            struct vmcb *vmcb12)
 308 {
 309         struct kvm_vcpu *vcpu = &svm->vcpu;
 310         u32 exit_int_info = 0;
 311         unsigned int nr;
 312
 313         if (vcpu->arch.exception.injected) {
 314                 nr = vcpu->arch.exception.nr;
 315                 exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT;
 316
 317                 if (vcpu->arch.exception.has_error_code) {
 318                         exit_int_info |= SVM_EVTINJ_VALID_ERR;
 319                         vmcb12->control.exit_int_info_err =
 320                                 vcpu->arch.exception.error_code;
 321                 }
 322
 323         } else if (vcpu->arch.nmi_injected) {
 324                 exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI;
 325
 326         } else if (vcpu->arch.interrupt.injected) {
 327                 nr = vcpu->arch.interrupt.nr;
 328                 exit_int_info = nr | SVM_EVTINJ_VALID;
 329
 330                 if (vcpu->arch.interrupt.soft)
 331                         exit_int_info |= SVM_EVTINJ_TYPE_SOFT;
 332                 else
 333                         exit_int_info |= SVM_EVTINJ_TYPE_INTR;
 334         }
 335
 336         vmcb12->control.exit_int_info = exit_int_info;
 337 }
 338
 339 static inline bool nested_npt_enabled(struct vcpu_svm *svm)
 340 {
 341         return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE;
 342 }
 343
 344 /*
 345  * Load guest's/host's cr3 on nested vmentry or vmexit. @nested_npt is true
 346  * if we are emulating VM-Entry into a guest with NPT enabled.
 347  */
 348 static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
 349                                bool nested_npt)
 350 {
 351         if (cr3 & rsvd_bits(cpuid_maxphyaddr(vcpu), 63))
 352                 return -EINVAL;
 353
 354         if (!nested_npt && is_pae_paging(vcpu) &&
 355             (cr3 != kvm_read_cr3(vcpu) || pdptrs_changed(vcpu))) {
 356                 if (!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3))
 357                         return -EINVAL;
 358         }
 359
 360         /*
 361          * TODO: optimize unconditional TLB flush/MMU sync here and in
 362          * kvm_init_shadow_npt_mmu().
 363          */
 364         if (!nested_npt)
 365                 kvm_mmu_new_pgd(vcpu, cr3, false, false);
 366
 367         vcpu->arch.cr3 = cr3;
 368         kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
 369
 370         kvm_init_mmu(vcpu, false);
 371
 372         return 0;
 373 }
 374
 375 static void nested_prepare_vmcb_save(struct vcpu_svm *svm, struct vmcb *vmcb12)
 376 {
 377         /* Load the nested guest state */
 378         svm->vmcb->save.es = vmcb12->save.es;
 379         svm->vmcb->save.cs = vmcb12->save.cs;
 380         svm->vmcb->save.ss = vmcb12->save.ss;
 381         svm->vmcb->save.ds = vmcb12->save.ds;
 382         svm->vmcb->save.gdtr = vmcb12->save.gdtr;
 383         svm->vmcb->save.idtr = vmcb12->save.idtr;
 384         kvm_set_rflags(&svm->vcpu, vmcb12->save.rflags);
 385         svm_set_efer(&svm->vcpu, vmcb12->save.efer);
 386         svm_set_cr0(&svm->vcpu, vmcb12->save.cr0);
 387         svm_set_cr4(&svm->vcpu, vmcb12->save.cr4);
 388         svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = vmcb12->save.cr2;
 389         kvm_rax_write(&svm->vcpu, vmcb12->save.rax);
 390         kvm_rsp_write(&svm->vcpu, vmcb12->save.rsp);
 391         kvm_rip_write(&svm->vcpu, vmcb12->save.rip);
 392
 393         /* In case we don't even reach vcpu_run, the fields are not updated */
 394         svm->vmcb->save.rax = vmcb12->save.rax;
 395         svm->vmcb->save.rsp = vmcb12->save.rsp;
 396         svm->vmcb->save.rip = vmcb12->save.rip;
 397         svm->vmcb->save.dr7 = vmcb12->save.dr7;
 398         svm->vcpu.arch.dr6  = vmcb12->save.dr6;
 399         svm->vmcb->save.cpl = vmcb12->save.cpl;
 400 }
 401
 402 static void nested_prepare_vmcb_control(struct vcpu_svm *svm)
 403 {
 404         const u32 mask = V_INTR_MASKING_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK;
 405
 406         if (nested_npt_enabled(svm))
 407                 nested_svm_init_mmu_context(&svm->vcpu);
 408
 409         svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset =
 410                 svm->vcpu.arch.l1_tsc_offset + svm->nested.ctl.tsc_offset;
 411
 412         svm->vmcb->control.int_ctl             =
 413                 (svm->nested.ctl.int_ctl & ~mask) |
 414                 (svm->nested.hsave->control.int_ctl & mask);
 415
 416         svm->vmcb->control.virt_ext            = svm->nested.ctl.virt_ext;
 417         svm->vmcb->control.int_vector          = svm->nested.ctl.int_vector;
 418         svm->vmcb->control.int_state           = svm->nested.ctl.int_state;
 419         svm->vmcb->control.event_inj           = svm->nested.ctl.event_inj;
 420         svm->vmcb->control.event_inj_err       = svm->nested.ctl.event_inj_err;
 421
 422         svm->vmcb->control.pause_filter_count  = svm->nested.ctl.pause_filter_count;
 423         svm->vmcb->control.pause_filter_thresh = svm->nested.ctl.pause_filter_thresh;
 424
 425         /* Enter Guest-Mode */
 426         enter_guest_mode(&svm->vcpu);
 427
 428         /*
 429          * Merge guest and host intercepts - must be called  with vcpu in
 430          * guest-mode to take affect here
 431          */
 432         recalc_intercepts(svm);
 433
 434         vmcb_mark_all_dirty(svm->vmcb);
 435 }
 436
 437 int enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb12_gpa,
 438                          struct vmcb *vmcb12)
 439 {
 440         int ret;
 441
 442         svm->nested.vmcb12_gpa = vmcb12_gpa;
 443         load_nested_vmcb_control(svm, &vmcb12->control);
 444         nested_prepare_vmcb_save(svm, vmcb12);
 445         nested_prepare_vmcb_control(svm);
 446
 447         ret = nested_svm_load_cr3(&svm->vcpu, vmcb12->save.cr3,
 448                                   nested_npt_enabled(svm));
 449         if (ret)
 450                 return ret;
 451
 452         svm_set_gif(svm, true);
 453
 454         return 0;
 455 }
 456
 457 int nested_svm_vmrun(struct vcpu_svm *svm)
 458 {
 459         int ret;
 460         struct vmcb *vmcb12;
 461         struct vmcb *hsave = svm->nested.hsave;
 462         struct vmcb *vmcb = svm->vmcb;
 463         struct kvm_host_map map;
 464         u64 vmcb12_gpa;
 465
 466         if (is_smm(&svm->vcpu)) {
 467                 kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 468                 return 1;
 469         }
 470
 471         vmcb12_gpa = svm->vmcb->save.rax;
 472         ret = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb12_gpa), &map);
 473         if (ret == -EINVAL) {
 474                 kvm_inject_gp(&svm->vcpu, 0);
 475                 return 1;
 476         } else if (ret) {
 477                 return kvm_skip_emulated_instruction(&svm->vcpu);
 478         }
 479
 480         ret = kvm_skip_emulated_instruction(&svm->vcpu);
 481
 482         vmcb12 = map.hva;
 483
 484         if (WARN_ON_ONCE(!svm->nested.initialized))
 485                 return -EINVAL;
 486
 487         if (!nested_vmcb_checks(svm, vmcb12)) {
 488                 vmcb12->control.exit_code    = SVM_EXIT_ERR;
 489                 vmcb12->control.exit_code_hi = 0;
 490                 vmcb12->control.exit_info_1  = 0;
 491                 vmcb12->control.exit_info_2  = 0;
 492                 goto out;
 493         }
 494
 495         trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb12_gpa,
 496                                vmcb12->save.rip,
 497                                vmcb12->control.int_ctl,
 498                                vmcb12->control.event_inj,
 499                                vmcb12->control.nested_ctl);
 500
 501         trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff,
 502                                     vmcb12->control.intercepts[INTERCEPT_CR] >> 16,
 503                                     vmcb12->control.intercepts[INTERCEPT_EXCEPTION],
 504                                     vmcb12->control.intercepts[INTERCEPT_WORD3],
 505                                     vmcb12->control.intercepts[INTERCEPT_WORD4],
 506                                     vmcb12->control.intercepts[INTERCEPT_WORD5]);
 507
 508         /* Clear internal status */
 509         kvm_clear_exception_queue(&svm->vcpu);
 510         kvm_clear_interrupt_queue(&svm->vcpu);
 511
 512         /*
 513          * Save the old vmcb, so we don't need to pick what we save, but can
 514          * restore everything when a VMEXIT occurs
 515          */
 516         hsave->save.es     = vmcb->save.es;
 517         hsave->save.cs     = vmcb->save.cs;
 518         hsave->save.ss     = vmcb->save.ss;
 519         hsave->save.ds     = vmcb->save.ds;
 520         hsave->save.gdtr   = vmcb->save.gdtr;
 521         hsave->save.idtr   = vmcb->save.idtr;
 522         hsave->save.efer   = svm->vcpu.arch.efer;
 523         hsave->save.cr0    = kvm_read_cr0(&svm->vcpu);
 524         hsave->save.cr4    = svm->vcpu.arch.cr4;
 525         hsave->save.rflags = kvm_get_rflags(&svm->vcpu);
 526         hsave->save.rip    = kvm_rip_read(&svm->vcpu);
 527         hsave->save.rsp    = vmcb->save.rsp;
 528         hsave->save.rax    = vmcb->save.rax;
 529         if (npt_enabled)
 530                 hsave->save.cr3    = vmcb->save.cr3;
 531         else
 532                 hsave->save.cr3    = kvm_read_cr3(&svm->vcpu);
 533
 534         copy_vmcb_control_area(&hsave->control, &vmcb->control);
 535
 536         svm->nested.nested_run_pending = 1;
 537
 538         if (enter_svm_guest_mode(svm, vmcb12_gpa, vmcb12))
 539                 goto out_exit_err;
 540
 541         if (nested_svm_vmrun_msrpm(svm))
 542                 goto out;
 543
 544 out_exit_err:
 545         svm->nested.nested_run_pending = 0;
 546
 547         svm->vmcb->control.exit_code    = SVM_EXIT_ERR;
 548         svm->vmcb->control.exit_code_hi = 0;
 549         svm->vmcb->control.exit_info_1  = 0;
 550         svm->vmcb->control.exit_info_2  = 0;
 551
 552         nested_svm_vmexit(svm);
 553
 554 out:
 555         kvm_vcpu_unmap(&svm->vcpu, &map, true);
 556
 557         return ret;
 558 }
 559
 560 void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
 561 {
 562         to_vmcb->save.fs = from_vmcb->save.fs;
 563         to_vmcb->save.gs = from_vmcb->save.gs;
 564         to_vmcb->save.tr = from_vmcb->save.tr;
 565         to_vmcb->save.ldtr = from_vmcb->save.ldtr;
 566         to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
 567         to_vmcb->save.star = from_vmcb->save.star;
 568         to_vmcb->save.lstar = from_vmcb->save.lstar;
 569         to_vmcb->save.cstar = from_vmcb->save.cstar;
 570         to_vmcb->save.sfmask = from_vmcb->save.sfmask;
 571         to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
 572         to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
 573         to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
 574 }
 575
 576 int nested_svm_vmexit(struct vcpu_svm *svm)
 577 {
 578         int rc;
 579         struct vmcb *vmcb12;
 580         struct vmcb *hsave = svm->nested.hsave;
 581         struct vmcb *vmcb = svm->vmcb;
 582         struct kvm_host_map map;
 583
 584         rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map);
 585         if (rc) {
 586                 if (rc == -EINVAL)
 587                         kvm_inject_gp(&svm->vcpu, 0);
 588                 return 1;
 589         }
 590
 591         vmcb12 = map.hva;
 592
 593         /* Exit Guest-Mode */
 594         leave_guest_mode(&svm->vcpu);
 595         svm->nested.vmcb12_gpa = 0;
 596         WARN_ON_ONCE(svm->nested.nested_run_pending);
 597
 598         /* in case we halted in L2 */
 599         svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE;
 600
 601         /* Give the current vmcb to the guest */
 602
 603         vmcb12->save.es     = vmcb->save.es;
 604         vmcb12->save.cs     = vmcb->save.cs;
 605         vmcb12->save.ss     = vmcb->save.ss;
 606         vmcb12->save.ds     = vmcb->save.ds;
 607         vmcb12->save.gdtr   = vmcb->save.gdtr;
 608         vmcb12->save.idtr   = vmcb->save.idtr;
 609         vmcb12->save.efer   = svm->vcpu.arch.efer;
 610         vmcb12->save.cr0    = kvm_read_cr0(&svm->vcpu);
 611         vmcb12->save.cr3    = kvm_read_cr3(&svm->vcpu);
 612         vmcb12->save.cr2    = vmcb->save.cr2;
 613         vmcb12->save.cr4    = svm->vcpu.arch.cr4;
 614         vmcb12->save.rflags = kvm_get_rflags(&svm->vcpu);
 615         vmcb12->save.rip    = kvm_rip_read(&svm->vcpu);
 616         vmcb12->save.rsp    = kvm_rsp_read(&svm->vcpu);
 617         vmcb12->save.rax    = kvm_rax_read(&svm->vcpu);
 618         vmcb12->save.dr7    = vmcb->save.dr7;
 619         vmcb12->save.dr6    = svm->vcpu.arch.dr6;
 620         vmcb12->save.cpl    = vmcb->save.cpl;
 621
 622         vmcb12->control.int_state         = vmcb->control.int_state;
 623         vmcb12->control.exit_code         = vmcb->control.exit_code;
 624         vmcb12->control.exit_code_hi      = vmcb->control.exit_code_hi;
 625         vmcb12->control.exit_info_1       = vmcb->control.exit_info_1;
 626         vmcb12->control.exit_info_2       = vmcb->control.exit_info_2;
 627
 628         if (vmcb12->control.exit_code != SVM_EXIT_ERR)
 629                 nested_vmcb_save_pending_event(svm, vmcb12);
 630
 631         if (svm->nrips_enabled)
 632                 vmcb12->control.next_rip  = vmcb->control.next_rip;
 633
 634         vmcb12->control.int_ctl           = svm->nested.ctl.int_ctl;
 635         vmcb12->control.tlb_ctl           = svm->nested.ctl.tlb_ctl;
 636         vmcb12->control.event_inj         = svm->nested.ctl.event_inj;
 637         vmcb12->control.event_inj_err     = svm->nested.ctl.event_inj_err;
 638
 639         vmcb12->control.pause_filter_count =
 640                 svm->vmcb->control.pause_filter_count;
 641         vmcb12->control.pause_filter_thresh =
 642                 svm->vmcb->control.pause_filter_thresh;
 643
 644         /* Restore the original control entries */
 645         copy_vmcb_control_area(&vmcb->control, &hsave->control);
 646
 647         /* On vmexit the  GIF is set to false */
 648         svm_set_gif(svm, false);
 649
 650         svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset =
 651                 svm->vcpu.arch.l1_tsc_offset;
 652
 653         svm->nested.ctl.nested_cr3 = 0;
 654
 655         /* Restore selected save entries */
 656         svm->vmcb->save.es = hsave->save.es;
 657         svm->vmcb->save.cs = hsave->save.cs;
 658         svm->vmcb->save.ss = hsave->save.ss;
 659         svm->vmcb->save.ds = hsave->save.ds;
 660         svm->vmcb->save.gdtr = hsave->save.gdtr;
 661         svm->vmcb->save.idtr = hsave->save.idtr;
 662         kvm_set_rflags(&svm->vcpu, hsave->save.rflags);
 663         svm_set_efer(&svm->vcpu, hsave->save.efer);
 664         svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE);
 665         svm_set_cr4(&svm->vcpu, hsave->save.cr4);
 666         kvm_rax_write(&svm->vcpu, hsave->save.rax);
 667         kvm_rsp_write(&svm->vcpu, hsave->save.rsp);
 668         kvm_rip_write(&svm->vcpu, hsave->save.rip);
 669         svm->vmcb->save.dr7 = 0;
 670         svm->vmcb->save.cpl = 0;
 671         svm->vmcb->control.exit_int_info = 0;
 672
 673         vmcb_mark_all_dirty(svm->vmcb);
 674
 675         trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code,
 676                                        vmcb12->control.exit_info_1,
 677                                        vmcb12->control.exit_info_2,
 678                                        vmcb12->control.exit_int_info,
 679                                        vmcb12->control.exit_int_info_err,
 680                                        KVM_ISA_SVM);
 681
 682         kvm_vcpu_unmap(&svm->vcpu, &map, true);
 683
 684         nested_svm_uninit_mmu_context(&svm->vcpu);
 685
 686         rc = nested_svm_load_cr3(&svm->vcpu, hsave->save.cr3, false);
 687         if (rc)
 688                 return 1;
 689
 690         if (npt_enabled)
 691                 svm->vmcb->save.cr3 = hsave->save.cr3;
 692
 693         /*
 694          * Drop what we picked up for L2 via svm_complete_interrupts() so it
 695          * doesn't end up in L1.
 696          */
 697         svm->vcpu.arch.nmi_injected = false;
 698         kvm_clear_exception_queue(&svm->vcpu);
 699         kvm_clear_interrupt_queue(&svm->vcpu);
 700
 701         return 0;
 702 }
 703
 704 int svm_allocate_nested(struct vcpu_svm *svm)
 705 {
 706         struct page *hsave_page;
 707
 708         if (svm->nested.initialized)
 709                 return 0;
 710
 711         hsave_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
 712         if (!hsave_page)
 713                 return -ENOMEM;
 714         svm->nested.hsave = page_address(hsave_page);
 715
 716         svm->nested.msrpm = svm_vcpu_alloc_msrpm();
 717         if (!svm->nested.msrpm)
 718                 goto err_free_hsave;
 719         svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm);
 720
 721         svm->nested.initialized = true;
 722         return 0;
 723
 724 err_free_hsave:
 725         __free_page(hsave_page);
 726         return -ENOMEM;
 727 }
 728
 729 void svm_free_nested(struct vcpu_svm *svm)
 730 {
 731         if (!svm->nested.initialized)
 732                 return;
 733
 734         svm_vcpu_free_msrpm(svm->nested.msrpm);
 735         svm->nested.msrpm = NULL;
 736
 737         __free_page(virt_to_page(svm->nested.hsave));
 738         svm->nested.hsave = NULL;
 739
 740         svm->nested.initialized = false;
 741 }
 742
 743 /*
 744  * Forcibly leave nested mode in order to be able to reset the VCPU later on.
 745  */
 746 void svm_leave_nested(struct vcpu_svm *svm)
 747 {
 748         if (is_guest_mode(&svm->vcpu)) {
 749                 struct vmcb *hsave = svm->nested.hsave;
 750                 struct vmcb *vmcb = svm->vmcb;
 751
 752                 svm->nested.nested_run_pending = 0;
 753                 leave_guest_mode(&svm->vcpu);
 754                 copy_vmcb_control_area(&vmcb->control, &hsave->control);
 755                 nested_svm_uninit_mmu_context(&svm->vcpu);
 756         }
 757
 758         kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->vcpu);
 759 }
 760
 761 static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
 762 {
 763         u32 offset, msr, value;
 764         int write, mask;
 765
 766         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
 767                 return NESTED_EXIT_HOST;
 768
 769         msr    = svm->vcpu.arch.regs[VCPU_REGS_RCX];
 770         offset = svm_msrpm_offset(msr);
 771         write  = svm->vmcb->control.exit_info_1 & 1;
 772         mask   = 1 << ((2 * (msr & 0xf)) + write);
 773
 774         if (offset == MSR_INVALID)
 775                 return NESTED_EXIT_DONE;
 776
 777         /* Offset is in 32 bit units but need in 8 bit units */
 778         offset *= 4;
 779
 780         if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4))
 781                 return NESTED_EXIT_DONE;
 782
 783         return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
 784 }
 785
 786 static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
 787 {
 788         unsigned port, size, iopm_len;
 789         u16 val, mask;
 790         u8 start_bit;
 791         u64 gpa;
 792
 793         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
 794                 return NESTED_EXIT_HOST;
 795
 796         port = svm->vmcb->control.exit_info_1 >> 16;
 797         size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >>
 798                 SVM_IOIO_SIZE_SHIFT;
 799         gpa  = svm->nested.ctl.iopm_base_pa + (port / 8);
 800         start_bit = port % 8;
 801         iopm_len = (start_bit + size > 8) ? 2 : 1;
 802         mask = (0xf >> (4 - size)) << start_bit;
 803         val = 0;
 804
 805         if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len))
 806                 return NESTED_EXIT_DONE;
 807
 808         return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
 809 }
 810
 811 static int nested_svm_intercept(struct vcpu_svm *svm)
 812 {
 813         u32 exit_code = svm->vmcb->control.exit_code;
 814         int vmexit = NESTED_EXIT_HOST;
 815
 816         switch (exit_code) {
 817         case SVM_EXIT_MSR:
 818                 vmexit = nested_svm_exit_handled_msr(svm);
 819                 break;
 820         case SVM_EXIT_IOIO:
 821                 vmexit = nested_svm_intercept_ioio(svm);
 822                 break;
 823         case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
 824                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 825                         vmexit = NESTED_EXIT_DONE;
 826                 break;
 827         }
 828         case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
 829                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 830                         vmexit = NESTED_EXIT_DONE;
 831                 break;
 832         }
 833         case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
 834                 /*
 835                  * Host-intercepted exceptions have been checked already in
 836                  * nested_svm_exit_special.  There is nothing to do here,
 837                  * the vmexit is injected by svm_check_nested_events.
 838                  */
 839                 vmexit = NESTED_EXIT_DONE;
 840                 break;
 841         }
 842         case SVM_EXIT_ERR: {
 843                 vmexit = NESTED_EXIT_DONE;
 844                 break;
 845         }
 846         default: {
 847                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 848                         vmexit = NESTED_EXIT_DONE;
 849         }
 850         }
 851
 852         return vmexit;
 853 }
 854
 855 int nested_svm_exit_handled(struct vcpu_svm *svm)
 856 {
 857         int vmexit;
 858
 859         vmexit = nested_svm_intercept(svm);
 860
 861         if (vmexit == NESTED_EXIT_DONE)
 862                 nested_svm_vmexit(svm);
 863
 864         return vmexit;
 865 }
 866
 867 int nested_svm_check_permissions(struct vcpu_svm *svm)
 868 {
 869         if (!(svm->vcpu.arch.efer & EFER_SVME) ||
 870             !is_paging(&svm->vcpu)) {
 871                 kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 872                 return 1;
 873         }
 874
 875         if (svm->vmcb->save.cpl) {
 876                 kvm_inject_gp(&svm->vcpu, 0);
 877                 return 1;
 878         }
 879
 880         return 0;
 881 }
 882
 883 static bool nested_exit_on_exception(struct vcpu_svm *svm)
 884 {
 885         unsigned int nr = svm->vcpu.arch.exception.nr;
 886
 887         return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(nr));
 888 }
 889
 890 static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm)
 891 {
 892         unsigned int nr = svm->vcpu.arch.exception.nr;
 893
 894         svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
 895         svm->vmcb->control.exit_code_hi = 0;
 896
 897         if (svm->vcpu.arch.exception.has_error_code)
 898                 svm->vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code;
 899
 900         /*
 901          * EXITINFO2 is undefined for all exception intercepts other
 902          * than #PF.
 903          */
 904         if (nr == PF_VECTOR) {
 905                 if (svm->vcpu.arch.exception.nested_apf)
 906                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token;
 907                 else if (svm->vcpu.arch.exception.has_payload)
 908                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload;
 909                 else
 910                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2;
 911         } else if (nr == DB_VECTOR) {
 912                 /* See inject_pending_event.  */
 913                 kvm_deliver_exception_payload(&svm->vcpu);
 914                 if (svm->vcpu.arch.dr7 & DR7_GD) {
 915                         svm->vcpu.arch.dr7 &= ~DR7_GD;
 916                         kvm_update_dr7(&svm->vcpu);
 917                 }
 918         } else
 919                 WARN_ON(svm->vcpu.arch.exception.has_payload);
 920
 921         nested_svm_vmexit(svm);
 922 }
 923
 924 static void nested_svm_smi(struct vcpu_svm *svm)
 925 {
 926         svm->vmcb->control.exit_code = SVM_EXIT_SMI;
 927         svm->vmcb->control.exit_info_1 = 0;
 928         svm->vmcb->control.exit_info_2 = 0;
 929
 930         nested_svm_vmexit(svm);
 931 }
 932
 933 static void nested_svm_nmi(struct vcpu_svm *svm)
 934 {
 935         svm->vmcb->control.exit_code = SVM_EXIT_NMI;
 936         svm->vmcb->control.exit_info_1 = 0;
 937         svm->vmcb->control.exit_info_2 = 0;
 938
 939         nested_svm_vmexit(svm);
 940 }
 941
 942 static void nested_svm_intr(struct vcpu_svm *svm)
 943 {
 944         trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
 945
 946         svm->vmcb->control.exit_code   = SVM_EXIT_INTR;
 947         svm->vmcb->control.exit_info_1 = 0;
 948         svm->vmcb->control.exit_info_2 = 0;
 949
 950         nested_svm_vmexit(svm);
 951 }
 952
 953 static inline bool nested_exit_on_init(struct vcpu_svm *svm)
 954 {
 955         return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
 956 }
 957
 958 static void nested_svm_init(struct vcpu_svm *svm)
 959 {
 960         svm->vmcb->control.exit_code   = SVM_EXIT_INIT;
 961         svm->vmcb->control.exit_info_1 = 0;
 962         svm->vmcb->control.exit_info_2 = 0;
 963
 964         nested_svm_vmexit(svm);
 965 }
 966
 967
 968 static int svm_check_nested_events(struct kvm_vcpu *vcpu)
 969 {
 970         struct vcpu_svm *svm = to_svm(vcpu);
 971         bool block_nested_events =
 972                 kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending;
 973         struct kvm_lapic *apic = vcpu->arch.apic;
 974
 975         if (lapic_in_kernel(vcpu) &&
 976             test_bit(KVM_APIC_INIT, &apic->pending_events)) {
 977                 if (block_nested_events)
 978                         return -EBUSY;
 979                 if (!nested_exit_on_init(svm))
 980                         return 0;
 981                 nested_svm_init(svm);
 982                 return 0;
 983         }
 984
 985         if (vcpu->arch.exception.pending) {
 986                 if (block_nested_events)
 987                         return -EBUSY;
 988                 if (!nested_exit_on_exception(svm))
 989                         return 0;
 990                 nested_svm_inject_exception_vmexit(svm);
 991                 return 0;
 992         }
 993
 994         if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
 995                 if (block_nested_events)
 996                         return -EBUSY;
 997                 if (!nested_exit_on_smi(svm))
 998                         return 0;
 999                 nested_svm_smi(svm);
1000                 return 0;
1001         }
1002
1003         if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
1004                 if (block_nested_events)
1005                         return -EBUSY;
1006                 if (!nested_exit_on_nmi(svm))
1007                         return 0;
1008                 nested_svm_nmi(svm);
1009                 return 0;
1010         }
1011
1012         if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
1013                 if (block_nested_events)
1014                         return -EBUSY;
1015                 if (!nested_exit_on_intr(svm))
1016                         return 0;
1017                 nested_svm_intr(svm);
1018                 return 0;
1019         }
1020
1021         return 0;
1022 }
1023
1024 int nested_svm_exit_special(struct vcpu_svm *svm)
1025 {
1026         u32 exit_code = svm->vmcb->control.exit_code;
1027
1028         switch (exit_code) {
1029         case SVM_EXIT_INTR:
1030         case SVM_EXIT_NMI:
1031         case SVM_EXIT_NPF:
1032                 return NESTED_EXIT_HOST;
1033         case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1034                 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
1035
1036                 if (get_host_vmcb(svm)->control.intercepts[INTERCEPT_EXCEPTION] &
1037                                 excp_bits)
1038                         return NESTED_EXIT_HOST;
1039                 else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR &&
1040                          svm->vcpu.arch.apf.host_apf_flags)
1041                         /* Trap async PF even if not shadowing */
1042                         return NESTED_EXIT_HOST;
1043                 break;
1044         }
1045         default:
1046                 break;
1047         }
1048
1049         return NESTED_EXIT_CONTINUE;
1050 }
1051
1052 static int svm_get_nested_state(struct kvm_vcpu *vcpu,
1053                                 struct kvm_nested_state __user *user_kvm_nested_state,
1054                                 u32 user_data_size)
1055 {
1056         struct vcpu_svm *svm;
1057         struct kvm_nested_state kvm_state = {
1058                 .flags = 0,
1059                 .format = KVM_STATE_NESTED_FORMAT_SVM,
1060                 .size = sizeof(kvm_state),
1061         };
1062         struct vmcb __user *user_vmcb = (struct vmcb __user *)
1063                 &user_kvm_nested_state->data.svm[0];
1064
1065         if (!vcpu)
1066                 return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE;
1067
1068         svm = to_svm(vcpu);
1069
1070         if (user_data_size < kvm_state.size)
1071                 goto out;
1072
1073         /* First fill in the header and copy it out.  */
1074         if (is_guest_mode(vcpu)) {
1075                 kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa;
1076                 kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
1077                 kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
1078
1079                 if (svm->nested.nested_run_pending)
1080                         kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING;
1081         }
1082
1083         if (gif_set(svm))
1084                 kvm_state.flags |= KVM_STATE_NESTED_GIF_SET;
1085
1086         if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state)))
1087                 return -EFAULT;
1088
1089         if (!is_guest_mode(vcpu))
1090                 goto out;
1091
1092         /*
1093          * Copy over the full size of the VMCB rather than just the size
1094          * of the structs.
1095          */
1096         if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
1097                 return -EFAULT;
1098         if (copy_to_user(&user_vmcb->control, &svm->nested.ctl,
1099                          sizeof(user_vmcb->control)))
1100                 return -EFAULT;
1101         if (copy_to_user(&user_vmcb->save, &svm->nested.hsave->save,
1102                          sizeof(user_vmcb->save)))
1103                 return -EFAULT;
1104
1105 out:
1106         return kvm_state.size;
1107 }
1108
1109 static int svm_set_nested_state(struct kvm_vcpu *vcpu,
1110                                 struct kvm_nested_state __user *user_kvm_nested_state,
1111                                 struct kvm_nested_state *kvm_state)
1112 {
1113         struct vcpu_svm *svm = to_svm(vcpu);
1114         struct vmcb *hsave = svm->nested.hsave;
1115         struct vmcb __user *user_vmcb = (struct vmcb __user *)
1116                 &user_kvm_nested_state->data.svm[0];
1117         struct vmcb_control_area *ctl;
1118         struct vmcb_save_area *save;
1119         int ret;
1120         u32 cr0;
1121
1122         BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
1123                      KVM_STATE_NESTED_SVM_VMCB_SIZE);
1124
1125         if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
1126                 return -EINVAL;
1127
1128         if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE |
1129                                  KVM_STATE_NESTED_RUN_PENDING |
1130                                  KVM_STATE_NESTED_GIF_SET))
1131                 return -EINVAL;
1132
1133         /*
1134          * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's
1135          * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed.
1136          */
1137         if (!(vcpu->arch.efer & EFER_SVME)) {
1138                 /* GIF=1 and no guest mode are required if SVME=0.  */
1139                 if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET)
1140                         return -EINVAL;
1141         }
1142
1143         /* SMM temporarily disables SVM, so we cannot be in guest mode.  */
1144         if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE))
1145                 return -EINVAL;
1146
1147         if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
1148                 svm_leave_nested(svm);
1149                 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1150                 return 0;
1151         }
1152
1153         if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
1154                 return -EINVAL;
1155         if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE)
1156                 return -EINVAL;
1157
1158         ret  = -ENOMEM;
1159         ctl  = kzalloc(sizeof(*ctl),  GFP_KERNEL);
1160         save = kzalloc(sizeof(*save), GFP_KERNEL);
1161         if (!ctl || !save)
1162                 goto out_free;
1163
1164         ret = -EFAULT;
1165         if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl)))
1166                 goto out_free;
1167         if (copy_from_user(save, &user_vmcb->save, sizeof(*save)))
1168                 goto out_free;
1169
1170         ret = -EINVAL;
1171         if (!nested_vmcb_check_controls(ctl))
1172                 goto out_free;
1173
1174         /*
1175          * Processor state contains L2 state.  Check that it is
1176          * valid for guest mode (see nested_vmcb_checks).
1177          */
1178         cr0 = kvm_read_cr0(vcpu);
1179         if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
1180                 goto out_free;
1181
1182         /*
1183          * Validate host state saved from before VMRUN (see
1184          * nested_svm_check_permissions).
1185          * TODO: validate reserved bits for all saved state.
1186          */
1187         if (!(save->cr0 & X86_CR0_PG))
1188                 goto out_free;
1189
1190         /*
1191          * All checks done, we can enter guest mode.  L1 control fields
1192          * come from the nested save state.  Guest state is already
1193          * in the registers, the save area of the nested state instead
1194          * contains saved L1 state.
1195          */
1196         copy_vmcb_control_area(&hsave->control, &svm->vmcb->control);
1197         hsave->save = *save;
1198
1199         svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;
1200         load_nested_vmcb_control(svm, ctl);
1201         nested_prepare_vmcb_control(svm);
1202
1203         kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1204         ret = 0;
1205 out_free:
1206         kfree(save);
1207         kfree(ctl);
1208
1209         return ret;
1210 }
1211
1212 struct kvm_x86_nested_ops svm_nested_ops = {
1213         .check_events = svm_check_nested_events,
1214         .get_nested_state_pages = svm_get_nested_state_pages,
1215         .get_state = svm_get_nested_state,
1216         .set_state = svm_set_nested_state,
1217 };