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_check_save(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 true;
 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         nested_prepare_vmcb_save(svm, vmcb12);
 444         nested_prepare_vmcb_control(svm);
 445
 446         ret = nested_svm_load_cr3(&svm->vcpu, vmcb12->save.cr3,
 447                                   nested_npt_enabled(svm));
 448         if (ret)
 449                 return ret;
 450
 451         svm_set_gif(svm, true);
 452
 453         return 0;
 454 }
 455
 456 int nested_svm_vmrun(struct vcpu_svm *svm)
 457 {
 458         int ret;
 459         struct vmcb *vmcb12;
 460         struct vmcb *hsave = svm->nested.hsave;
 461         struct vmcb *vmcb = svm->vmcb;
 462         struct kvm_host_map map;
 463         u64 vmcb12_gpa;
 464
 465         if (is_smm(&svm->vcpu)) {
 466                 kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 467                 return 1;
 468         }
 469
 470         vmcb12_gpa = svm->vmcb->save.rax;
 471         ret = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb12_gpa), &map);
 472         if (ret == -EINVAL) {
 473                 kvm_inject_gp(&svm->vcpu, 0);
 474                 return 1;
 475         } else if (ret) {
 476                 return kvm_skip_emulated_instruction(&svm->vcpu);
 477         }
 478
 479         ret = kvm_skip_emulated_instruction(&svm->vcpu);
 480
 481         vmcb12 = map.hva;
 482
 483         if (WARN_ON_ONCE(!svm->nested.initialized))
 484                 return -EINVAL;
 485
 486         load_nested_vmcb_control(svm, &vmcb12->control);
 487
 488         if (!nested_vmcb_check_save(svm, vmcb12) ||
 489             !nested_vmcb_check_controls(&svm->nested.ctl)) {
 490                 vmcb12->control.exit_code    = SVM_EXIT_ERR;
 491                 vmcb12->control.exit_code_hi = 0;
 492                 vmcb12->control.exit_info_1  = 0;
 493                 vmcb12->control.exit_info_2  = 0;
 494                 goto out;
 495         }
 496
 497         trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb12_gpa,
 498                                vmcb12->save.rip,
 499                                vmcb12->control.int_ctl,
 500                                vmcb12->control.event_inj,
 501                                vmcb12->control.nested_ctl);
 502
 503         trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff,
 504                                     vmcb12->control.intercepts[INTERCEPT_CR] >> 16,
 505                                     vmcb12->control.intercepts[INTERCEPT_EXCEPTION],
 506                                     vmcb12->control.intercepts[INTERCEPT_WORD3],
 507                                     vmcb12->control.intercepts[INTERCEPT_WORD4],
 508                                     vmcb12->control.intercepts[INTERCEPT_WORD5]);
 509
 510         /* Clear internal status */
 511         kvm_clear_exception_queue(&svm->vcpu);
 512         kvm_clear_interrupt_queue(&svm->vcpu);
 513
 514         /*
 515          * Save the old vmcb, so we don't need to pick what we save, but can
 516          * restore everything when a VMEXIT occurs
 517          */
 518         hsave->save.es     = vmcb->save.es;
 519         hsave->save.cs     = vmcb->save.cs;
 520         hsave->save.ss     = vmcb->save.ss;
 521         hsave->save.ds     = vmcb->save.ds;
 522         hsave->save.gdtr   = vmcb->save.gdtr;
 523         hsave->save.idtr   = vmcb->save.idtr;
 524         hsave->save.efer   = svm->vcpu.arch.efer;
 525         hsave->save.cr0    = kvm_read_cr0(&svm->vcpu);
 526         hsave->save.cr4    = svm->vcpu.arch.cr4;
 527         hsave->save.rflags = kvm_get_rflags(&svm->vcpu);
 528         hsave->save.rip    = kvm_rip_read(&svm->vcpu);
 529         hsave->save.rsp    = vmcb->save.rsp;
 530         hsave->save.rax    = vmcb->save.rax;
 531         if (npt_enabled)
 532                 hsave->save.cr3    = vmcb->save.cr3;
 533         else
 534                 hsave->save.cr3    = kvm_read_cr3(&svm->vcpu);
 535
 536         copy_vmcb_control_area(&hsave->control, &vmcb->control);
 537
 538         svm->nested.nested_run_pending = 1;
 539
 540         if (enter_svm_guest_mode(svm, vmcb12_gpa, vmcb12))
 541                 goto out_exit_err;
 542
 543         if (nested_svm_vmrun_msrpm(svm))
 544                 goto out;
 545
 546 out_exit_err:
 547         svm->nested.nested_run_pending = 0;
 548
 549         svm->vmcb->control.exit_code    = SVM_EXIT_ERR;
 550         svm->vmcb->control.exit_code_hi = 0;
 551         svm->vmcb->control.exit_info_1  = 0;
 552         svm->vmcb->control.exit_info_2  = 0;
 553
 554         nested_svm_vmexit(svm);
 555
 556 out:
 557         kvm_vcpu_unmap(&svm->vcpu, &map, true);
 558
 559         return ret;
 560 }
 561
 562 void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
 563 {
 564         to_vmcb->save.fs = from_vmcb->save.fs;
 565         to_vmcb->save.gs = from_vmcb->save.gs;
 566         to_vmcb->save.tr = from_vmcb->save.tr;
 567         to_vmcb->save.ldtr = from_vmcb->save.ldtr;
 568         to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
 569         to_vmcb->save.star = from_vmcb->save.star;
 570         to_vmcb->save.lstar = from_vmcb->save.lstar;
 571         to_vmcb->save.cstar = from_vmcb->save.cstar;
 572         to_vmcb->save.sfmask = from_vmcb->save.sfmask;
 573         to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
 574         to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
 575         to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
 576 }
 577
 578 int nested_svm_vmexit(struct vcpu_svm *svm)
 579 {
 580         int rc;
 581         struct vmcb *vmcb12;
 582         struct vmcb *hsave = svm->nested.hsave;
 583         struct vmcb *vmcb = svm->vmcb;
 584         struct kvm_host_map map;
 585
 586         rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map);
 587         if (rc) {
 588                 if (rc == -EINVAL)
 589                         kvm_inject_gp(&svm->vcpu, 0);
 590                 return 1;
 591         }
 592
 593         vmcb12 = map.hva;
 594
 595         /* Exit Guest-Mode */
 596         leave_guest_mode(&svm->vcpu);
 597         svm->nested.vmcb12_gpa = 0;
 598         WARN_ON_ONCE(svm->nested.nested_run_pending);
 599
 600         /* in case we halted in L2 */
 601         svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE;
 602
 603         /* Give the current vmcb to the guest */
 604
 605         vmcb12->save.es     = vmcb->save.es;
 606         vmcb12->save.cs     = vmcb->save.cs;
 607         vmcb12->save.ss     = vmcb->save.ss;
 608         vmcb12->save.ds     = vmcb->save.ds;
 609         vmcb12->save.gdtr   = vmcb->save.gdtr;
 610         vmcb12->save.idtr   = vmcb->save.idtr;
 611         vmcb12->save.efer   = svm->vcpu.arch.efer;
 612         vmcb12->save.cr0    = kvm_read_cr0(&svm->vcpu);
 613         vmcb12->save.cr3    = kvm_read_cr3(&svm->vcpu);
 614         vmcb12->save.cr2    = vmcb->save.cr2;
 615         vmcb12->save.cr4    = svm->vcpu.arch.cr4;
 616         vmcb12->save.rflags = kvm_get_rflags(&svm->vcpu);
 617         vmcb12->save.rip    = kvm_rip_read(&svm->vcpu);
 618         vmcb12->save.rsp    = kvm_rsp_read(&svm->vcpu);
 619         vmcb12->save.rax    = kvm_rax_read(&svm->vcpu);
 620         vmcb12->save.dr7    = vmcb->save.dr7;
 621         vmcb12->save.dr6    = svm->vcpu.arch.dr6;
 622         vmcb12->save.cpl    = vmcb->save.cpl;
 623
 624         vmcb12->control.int_state         = vmcb->control.int_state;
 625         vmcb12->control.exit_code         = vmcb->control.exit_code;
 626         vmcb12->control.exit_code_hi      = vmcb->control.exit_code_hi;
 627         vmcb12->control.exit_info_1       = vmcb->control.exit_info_1;
 628         vmcb12->control.exit_info_2       = vmcb->control.exit_info_2;
 629
 630         if (vmcb12->control.exit_code != SVM_EXIT_ERR)
 631                 nested_vmcb_save_pending_event(svm, vmcb12);
 632
 633         if (svm->nrips_enabled)
 634                 vmcb12->control.next_rip  = vmcb->control.next_rip;
 635
 636         vmcb12->control.int_ctl           = svm->nested.ctl.int_ctl;
 637         vmcb12->control.tlb_ctl           = svm->nested.ctl.tlb_ctl;
 638         vmcb12->control.event_inj         = svm->nested.ctl.event_inj;
 639         vmcb12->control.event_inj_err     = svm->nested.ctl.event_inj_err;
 640
 641         vmcb12->control.pause_filter_count =
 642                 svm->vmcb->control.pause_filter_count;
 643         vmcb12->control.pause_filter_thresh =
 644                 svm->vmcb->control.pause_filter_thresh;
 645
 646         /* Restore the original control entries */
 647         copy_vmcb_control_area(&vmcb->control, &hsave->control);
 648
 649         /* On vmexit the  GIF is set to false */
 650         svm_set_gif(svm, false);
 651
 652         svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset =
 653                 svm->vcpu.arch.l1_tsc_offset;
 654
 655         svm->nested.ctl.nested_cr3 = 0;
 656
 657         /* Restore selected save entries */
 658         svm->vmcb->save.es = hsave->save.es;
 659         svm->vmcb->save.cs = hsave->save.cs;
 660         svm->vmcb->save.ss = hsave->save.ss;
 661         svm->vmcb->save.ds = hsave->save.ds;
 662         svm->vmcb->save.gdtr = hsave->save.gdtr;
 663         svm->vmcb->save.idtr = hsave->save.idtr;
 664         kvm_set_rflags(&svm->vcpu, hsave->save.rflags);
 665         svm_set_efer(&svm->vcpu, hsave->save.efer);
 666         svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE);
 667         svm_set_cr4(&svm->vcpu, hsave->save.cr4);
 668         kvm_rax_write(&svm->vcpu, hsave->save.rax);
 669         kvm_rsp_write(&svm->vcpu, hsave->save.rsp);
 670         kvm_rip_write(&svm->vcpu, hsave->save.rip);
 671         svm->vmcb->save.dr7 = 0;
 672         svm->vmcb->save.cpl = 0;
 673         svm->vmcb->control.exit_int_info = 0;
 674
 675         vmcb_mark_all_dirty(svm->vmcb);
 676
 677         trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code,
 678                                        vmcb12->control.exit_info_1,
 679                                        vmcb12->control.exit_info_2,
 680                                        vmcb12->control.exit_int_info,
 681                                        vmcb12->control.exit_int_info_err,
 682                                        KVM_ISA_SVM);
 683
 684         kvm_vcpu_unmap(&svm->vcpu, &map, true);
 685
 686         nested_svm_uninit_mmu_context(&svm->vcpu);
 687
 688         rc = nested_svm_load_cr3(&svm->vcpu, hsave->save.cr3, false);
 689         if (rc)
 690                 return 1;
 691
 692         if (npt_enabled)
 693                 svm->vmcb->save.cr3 = hsave->save.cr3;
 694
 695         /*
 696          * Drop what we picked up for L2 via svm_complete_interrupts() so it
 697          * doesn't end up in L1.
 698          */
 699         svm->vcpu.arch.nmi_injected = false;
 700         kvm_clear_exception_queue(&svm->vcpu);
 701         kvm_clear_interrupt_queue(&svm->vcpu);
 702
 703         return 0;
 704 }
 705
 706 int svm_allocate_nested(struct vcpu_svm *svm)
 707 {
 708         struct page *hsave_page;
 709
 710         if (svm->nested.initialized)
 711                 return 0;
 712
 713         hsave_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
 714         if (!hsave_page)
 715                 return -ENOMEM;
 716         svm->nested.hsave = page_address(hsave_page);
 717
 718         svm->nested.msrpm = svm_vcpu_alloc_msrpm();
 719         if (!svm->nested.msrpm)
 720                 goto err_free_hsave;
 721         svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm);
 722
 723         svm->nested.initialized = true;
 724         return 0;
 725
 726 err_free_hsave:
 727         __free_page(hsave_page);
 728         return -ENOMEM;
 729 }
 730
 731 void svm_free_nested(struct vcpu_svm *svm)
 732 {
 733         if (!svm->nested.initialized)
 734                 return;
 735
 736         svm_vcpu_free_msrpm(svm->nested.msrpm);
 737         svm->nested.msrpm = NULL;
 738
 739         __free_page(virt_to_page(svm->nested.hsave));
 740         svm->nested.hsave = NULL;
 741
 742         svm->nested.initialized = false;
 743 }
 744
 745 /*
 746  * Forcibly leave nested mode in order to be able to reset the VCPU later on.
 747  */
 748 void svm_leave_nested(struct vcpu_svm *svm)
 749 {
 750         if (is_guest_mode(&svm->vcpu)) {
 751                 struct vmcb *hsave = svm->nested.hsave;
 752                 struct vmcb *vmcb = svm->vmcb;
 753
 754                 svm->nested.nested_run_pending = 0;
 755                 leave_guest_mode(&svm->vcpu);
 756                 copy_vmcb_control_area(&vmcb->control, &hsave->control);
 757                 nested_svm_uninit_mmu_context(&svm->vcpu);
 758         }
 759
 760         kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->vcpu);
 761 }
 762
 763 static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
 764 {
 765         u32 offset, msr, value;
 766         int write, mask;
 767
 768         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
 769                 return NESTED_EXIT_HOST;
 770
 771         msr    = svm->vcpu.arch.regs[VCPU_REGS_RCX];
 772         offset = svm_msrpm_offset(msr);
 773         write  = svm->vmcb->control.exit_info_1 & 1;
 774         mask   = 1 << ((2 * (msr & 0xf)) + write);
 775
 776         if (offset == MSR_INVALID)
 777                 return NESTED_EXIT_DONE;
 778
 779         /* Offset is in 32 bit units but need in 8 bit units */
 780         offset *= 4;
 781
 782         if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4))
 783                 return NESTED_EXIT_DONE;
 784
 785         return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
 786 }
 787
 788 static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
 789 {
 790         unsigned port, size, iopm_len;
 791         u16 val, mask;
 792         u8 start_bit;
 793         u64 gpa;
 794
 795         if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
 796                 return NESTED_EXIT_HOST;
 797
 798         port = svm->vmcb->control.exit_info_1 >> 16;
 799         size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >>
 800                 SVM_IOIO_SIZE_SHIFT;
 801         gpa  = svm->nested.ctl.iopm_base_pa + (port / 8);
 802         start_bit = port % 8;
 803         iopm_len = (start_bit + size > 8) ? 2 : 1;
 804         mask = (0xf >> (4 - size)) << start_bit;
 805         val = 0;
 806
 807         if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len))
 808                 return NESTED_EXIT_DONE;
 809
 810         return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
 811 }
 812
 813 static int nested_svm_intercept(struct vcpu_svm *svm)
 814 {
 815         u32 exit_code = svm->vmcb->control.exit_code;
 816         int vmexit = NESTED_EXIT_HOST;
 817
 818         switch (exit_code) {
 819         case SVM_EXIT_MSR:
 820                 vmexit = nested_svm_exit_handled_msr(svm);
 821                 break;
 822         case SVM_EXIT_IOIO:
 823                 vmexit = nested_svm_intercept_ioio(svm);
 824                 break;
 825         case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
 826                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 827                         vmexit = NESTED_EXIT_DONE;
 828                 break;
 829         }
 830         case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
 831                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 832                         vmexit = NESTED_EXIT_DONE;
 833                 break;
 834         }
 835         case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
 836                 /*
 837                  * Host-intercepted exceptions have been checked already in
 838                  * nested_svm_exit_special.  There is nothing to do here,
 839                  * the vmexit is injected by svm_check_nested_events.
 840                  */
 841                 vmexit = NESTED_EXIT_DONE;
 842                 break;
 843         }
 844         case SVM_EXIT_ERR: {
 845                 vmexit = NESTED_EXIT_DONE;
 846                 break;
 847         }
 848         default: {
 849                 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
 850                         vmexit = NESTED_EXIT_DONE;
 851         }
 852         }
 853
 854         return vmexit;
 855 }
 856
 857 int nested_svm_exit_handled(struct vcpu_svm *svm)
 858 {
 859         int vmexit;
 860
 861         vmexit = nested_svm_intercept(svm);
 862
 863         if (vmexit == NESTED_EXIT_DONE)
 864                 nested_svm_vmexit(svm);
 865
 866         return vmexit;
 867 }
 868
 869 int nested_svm_check_permissions(struct vcpu_svm *svm)
 870 {
 871         if (!(svm->vcpu.arch.efer & EFER_SVME) ||
 872             !is_paging(&svm->vcpu)) {
 873                 kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 874                 return 1;
 875         }
 876
 877         if (svm->vmcb->save.cpl) {
 878                 kvm_inject_gp(&svm->vcpu, 0);
 879                 return 1;
 880         }
 881
 882         return 0;
 883 }
 884
 885 static bool nested_exit_on_exception(struct vcpu_svm *svm)
 886 {
 887         unsigned int nr = svm->vcpu.arch.exception.nr;
 888
 889         return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(nr));
 890 }
 891
 892 static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm)
 893 {
 894         unsigned int nr = svm->vcpu.arch.exception.nr;
 895
 896         svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
 897         svm->vmcb->control.exit_code_hi = 0;
 898
 899         if (svm->vcpu.arch.exception.has_error_code)
 900                 svm->vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code;
 901
 902         /*
 903          * EXITINFO2 is undefined for all exception intercepts other
 904          * than #PF.
 905          */
 906         if (nr == PF_VECTOR) {
 907                 if (svm->vcpu.arch.exception.nested_apf)
 908                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token;
 909                 else if (svm->vcpu.arch.exception.has_payload)
 910                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload;
 911                 else
 912                         svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2;
 913         } else if (nr == DB_VECTOR) {
 914                 /* See inject_pending_event.  */
 915                 kvm_deliver_exception_payload(&svm->vcpu);
 916                 if (svm->vcpu.arch.dr7 & DR7_GD) {
 917                         svm->vcpu.arch.dr7 &= ~DR7_GD;
 918                         kvm_update_dr7(&svm->vcpu);
 919                 }
 920         } else
 921                 WARN_ON(svm->vcpu.arch.exception.has_payload);
 922
 923         nested_svm_vmexit(svm);
 924 }
 925
 926 static void nested_svm_smi(struct vcpu_svm *svm)
 927 {
 928         svm->vmcb->control.exit_code = SVM_EXIT_SMI;
 929         svm->vmcb->control.exit_info_1 = 0;
 930         svm->vmcb->control.exit_info_2 = 0;
 931
 932         nested_svm_vmexit(svm);
 933 }
 934
 935 static void nested_svm_nmi(struct vcpu_svm *svm)
 936 {
 937         svm->vmcb->control.exit_code = SVM_EXIT_NMI;
 938         svm->vmcb->control.exit_info_1 = 0;
 939         svm->vmcb->control.exit_info_2 = 0;
 940
 941         nested_svm_vmexit(svm);
 942 }
 943
 944 static void nested_svm_intr(struct vcpu_svm *svm)
 945 {
 946         trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
 947
 948         svm->vmcb->control.exit_code   = SVM_EXIT_INTR;
 949         svm->vmcb->control.exit_info_1 = 0;
 950         svm->vmcb->control.exit_info_2 = 0;
 951
 952         nested_svm_vmexit(svm);
 953 }
 954
 955 static inline bool nested_exit_on_init(struct vcpu_svm *svm)
 956 {
 957         return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
 958 }
 959
 960 static void nested_svm_init(struct vcpu_svm *svm)
 961 {
 962         svm->vmcb->control.exit_code   = SVM_EXIT_INIT;
 963         svm->vmcb->control.exit_info_1 = 0;
 964         svm->vmcb->control.exit_info_2 = 0;
 965
 966         nested_svm_vmexit(svm);
 967 }
 968
 969
 970 static int svm_check_nested_events(struct kvm_vcpu *vcpu)
 971 {
 972         struct vcpu_svm *svm = to_svm(vcpu);
 973         bool block_nested_events =
 974                 kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending;
 975         struct kvm_lapic *apic = vcpu->arch.apic;
 976
 977         if (lapic_in_kernel(vcpu) &&
 978             test_bit(KVM_APIC_INIT, &apic->pending_events)) {
 979                 if (block_nested_events)
 980                         return -EBUSY;
 981                 if (!nested_exit_on_init(svm))
 982                         return 0;
 983                 nested_svm_init(svm);
 984                 return 0;
 985         }
 986
 987         if (vcpu->arch.exception.pending) {
 988                 if (block_nested_events)
 989                         return -EBUSY;
 990                 if (!nested_exit_on_exception(svm))
 991                         return 0;
 992                 nested_svm_inject_exception_vmexit(svm);
 993                 return 0;
 994         }
 995
 996         if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
 997                 if (block_nested_events)
 998                         return -EBUSY;
 999                 if (!nested_exit_on_smi(svm))
1000                         return 0;
1001                 nested_svm_smi(svm);
1002                 return 0;
1003         }
1004
1005         if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
1006                 if (block_nested_events)
1007                         return -EBUSY;
1008                 if (!nested_exit_on_nmi(svm))
1009                         return 0;
1010                 nested_svm_nmi(svm);
1011                 return 0;
1012         }
1013
1014         if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
1015                 if (block_nested_events)
1016                         return -EBUSY;
1017                 if (!nested_exit_on_intr(svm))
1018                         return 0;
1019                 nested_svm_intr(svm);
1020                 return 0;
1021         }
1022
1023         return 0;
1024 }
1025
1026 int nested_svm_exit_special(struct vcpu_svm *svm)
1027 {
1028         u32 exit_code = svm->vmcb->control.exit_code;
1029
1030         switch (exit_code) {
1031         case SVM_EXIT_INTR:
1032         case SVM_EXIT_NMI:
1033         case SVM_EXIT_NPF:
1034                 return NESTED_EXIT_HOST;
1035         case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1036                 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
1037
1038                 if (get_host_vmcb(svm)->control.intercepts[INTERCEPT_EXCEPTION] &
1039                                 excp_bits)
1040                         return NESTED_EXIT_HOST;
1041                 else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR &&
1042                          svm->vcpu.arch.apf.host_apf_flags)
1043                         /* Trap async PF even if not shadowing */
1044                         return NESTED_EXIT_HOST;
1045                 break;
1046         }
1047         default:
1048                 break;
1049         }
1050
1051         return NESTED_EXIT_CONTINUE;
1052 }
1053
1054 static int svm_get_nested_state(struct kvm_vcpu *vcpu,
1055                                 struct kvm_nested_state __user *user_kvm_nested_state,
1056                                 u32 user_data_size)
1057 {
1058         struct vcpu_svm *svm;
1059         struct kvm_nested_state kvm_state = {
1060                 .flags = 0,
1061                 .format = KVM_STATE_NESTED_FORMAT_SVM,
1062                 .size = sizeof(kvm_state),
1063         };
1064         struct vmcb __user *user_vmcb = (struct vmcb __user *)
1065                 &user_kvm_nested_state->data.svm[0];
1066
1067         if (!vcpu)
1068                 return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE;
1069
1070         svm = to_svm(vcpu);
1071
1072         if (user_data_size < kvm_state.size)
1073                 goto out;
1074
1075         /* First fill in the header and copy it out.  */
1076         if (is_guest_mode(vcpu)) {
1077                 kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa;
1078                 kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
1079                 kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
1080
1081                 if (svm->nested.nested_run_pending)
1082                         kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING;
1083         }
1084
1085         if (gif_set(svm))
1086                 kvm_state.flags |= KVM_STATE_NESTED_GIF_SET;
1087
1088         if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state)))
1089                 return -EFAULT;
1090
1091         if (!is_guest_mode(vcpu))
1092                 goto out;
1093
1094         /*
1095          * Copy over the full size of the VMCB rather than just the size
1096          * of the structs.
1097          */
1098         if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
1099                 return -EFAULT;
1100         if (copy_to_user(&user_vmcb->control, &svm->nested.ctl,
1101                          sizeof(user_vmcb->control)))
1102                 return -EFAULT;
1103         if (copy_to_user(&user_vmcb->save, &svm->nested.hsave->save,
1104                          sizeof(user_vmcb->save)))
1105                 return -EFAULT;
1106
1107 out:
1108         return kvm_state.size;
1109 }
1110
1111 static int svm_set_nested_state(struct kvm_vcpu *vcpu,
1112                                 struct kvm_nested_state __user *user_kvm_nested_state,
1113                                 struct kvm_nested_state *kvm_state)
1114 {
1115         struct vcpu_svm *svm = to_svm(vcpu);
1116         struct vmcb *hsave = svm->nested.hsave;
1117         struct vmcb __user *user_vmcb = (struct vmcb __user *)
1118                 &user_kvm_nested_state->data.svm[0];
1119         struct vmcb_control_area *ctl;
1120         struct vmcb_save_area *save;
1121         int ret;
1122         u32 cr0;
1123
1124         BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
1125                      KVM_STATE_NESTED_SVM_VMCB_SIZE);
1126
1127         if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
1128                 return -EINVAL;
1129
1130         if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE |
1131                                  KVM_STATE_NESTED_RUN_PENDING |
1132                                  KVM_STATE_NESTED_GIF_SET))
1133                 return -EINVAL;
1134
1135         /*
1136          * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's
1137          * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed.
1138          */
1139         if (!(vcpu->arch.efer & EFER_SVME)) {
1140                 /* GIF=1 and no guest mode are required if SVME=0.  */
1141                 if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET)
1142                         return -EINVAL;
1143         }
1144
1145         /* SMM temporarily disables SVM, so we cannot be in guest mode.  */
1146         if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE))
1147                 return -EINVAL;
1148
1149         if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
1150                 svm_leave_nested(svm);
1151                 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1152                 return 0;
1153         }
1154
1155         if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
1156                 return -EINVAL;
1157         if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE)
1158                 return -EINVAL;
1159
1160         ret  = -ENOMEM;
1161         ctl  = kzalloc(sizeof(*ctl),  GFP_KERNEL);
1162         save = kzalloc(sizeof(*save), GFP_KERNEL);
1163         if (!ctl || !save)
1164                 goto out_free;
1165
1166         ret = -EFAULT;
1167         if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl)))
1168                 goto out_free;
1169         if (copy_from_user(save, &user_vmcb->save, sizeof(*save)))
1170                 goto out_free;
1171
1172         ret = -EINVAL;
1173         if (!nested_vmcb_check_controls(ctl))
1174                 goto out_free;
1175
1176         /*
1177          * Processor state contains L2 state.  Check that it is
1178          * valid for guest mode (see nested_vmcb_checks).
1179          */
1180         cr0 = kvm_read_cr0(vcpu);
1181         if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
1182                 goto out_free;
1183
1184         /*
1185          * Validate host state saved from before VMRUN (see
1186          * nested_svm_check_permissions).
1187          * TODO: validate reserved bits for all saved state.
1188          */
1189         if (!(save->cr0 & X86_CR0_PG))
1190                 goto out_free;
1191
1192         /*
1193          * All checks done, we can enter guest mode.  L1 control fields
1194          * come from the nested save state.  Guest state is already
1195          * in the registers, the save area of the nested state instead
1196          * contains saved L1 state.
1197          */
1198         copy_vmcb_control_area(&hsave->control, &svm->vmcb->control);
1199         hsave->save = *save;
1200
1201         svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;
1202         load_nested_vmcb_control(svm, ctl);
1203         nested_prepare_vmcb_control(svm);
1204
1205         kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1206         ret = 0;
1207 out_free:
1208         kfree(save);
1209         kfree(ctl);
1210
1211         return ret;
1212 }
1213
1214 struct kvm_x86_nested_ops svm_nested_ops = {
1215         .check_events = svm_check_nested_events,
1216         .get_nested_state_pages = svm_get_nested_state_pages,
1217         .get_state = svm_get_nested_state,
1218         .set_state = svm_set_nested_state,
1219 };