1
linux/arch/x86/kvm/svm/nested.c
Sean Christopherson f559b2e9c5 KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory
Ignore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits
4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't
enforce 32-byte alignment of nCR3.

In the absolute worst case scenario, failure to ignore bits 4:0 can result
in an out-of-bounds read, e.g. if the target page is at the end of a
memslot, and the VMM isn't using guard pages.

Per the APM:

  The CR3 register points to the base address of the page-directory-pointer
  table. The page-directory-pointer table is aligned on a 32-byte boundary,
  with the low 5 address bits 4:0 assumed to be 0.

And the SDM's much more explicit:

  4:0    Ignored

Note, KVM gets this right when loading PDPTRs, it's only the nSVM flow
that is broken.

Fixes: e4e517b4be ("KVM: MMU: Do not unconditionally read PDPTE from guest memory")
Reported-by: Kirk Swidowski <swidowski@google.com>
Cc: Andy Nguyen <theflow@google.com>
Cc: 3pvd <3pvd@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20241009140838.1036226-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-20 07:31:06 -04:00

1825 lines
51 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Kernel-based Virtual Machine driver for Linux
*
* AMD SVM support
*
* Copyright (C) 2006 Qumranet, Inc.
* Copyright 2010 Red Hat, Inc. and/or its affiliates.
*
* Authors:
* Yaniv Kamay <yaniv@qumranet.com>
* Avi Kivity <avi@qumranet.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kvm_types.h>
#include <linux/kvm_host.h>
#include <linux/kernel.h>
#include <asm/msr-index.h>
#include <asm/debugreg.h>
#include "kvm_emulate.h"
#include "trace.h"
#include "mmu.h"
#include "x86.h"
#include "smm.h"
#include "cpuid.h"
#include "lapic.h"
#include "svm.h"
#include "hyperv.h"
#define CC KVM_NESTED_VMENTER_CONSISTENCY_CHECK
static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
struct x86_exception *fault)
{
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb *vmcb = svm->vmcb;
if (vmcb->control.exit_code != SVM_EXIT_NPF) {
/*
* TODO: track the cause of the nested page fault, and
* correctly fill in the high bits of exit_info_1.
*/
vmcb->control.exit_code = SVM_EXIT_NPF;
vmcb->control.exit_code_hi = 0;
vmcb->control.exit_info_1 = (1ULL << 32);
vmcb->control.exit_info_2 = fault->address;
}
vmcb->control.exit_info_1 &= ~0xffffffffULL;
vmcb->control.exit_info_1 |= fault->error_code;
nested_svm_vmexit(svm);
}
static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index)
{
struct vcpu_svm *svm = to_svm(vcpu);
u64 cr3 = svm->nested.ctl.nested_cr3;
u64 pdpte;
int ret;
/*
* Note, nCR3 is "assumed" to be 32-byte aligned, i.e. the CPU ignores
* nCR3[4:0] when loading PDPTEs from memory.
*/
ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(cr3), &pdpte,
(cr3 & GENMASK(11, 5)) + index * 8, 8);
if (ret)
return 0;
return pdpte;
}
static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
return svm->nested.ctl.nested_cr3;
}
static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
WARN_ON(mmu_is_nested(vcpu));
vcpu->arch.mmu = &vcpu->arch.guest_mmu;
/*
* The NPT format depends on L1's CR4 and EFER, which is in vmcb01. Note,
* when called via KVM_SET_NESTED_STATE, that state may _not_ match current
* vCPU state. CR0.WP is explicitly ignored, while CR0.PG is required.
*/
kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, svm->vmcb01.ptr->save.cr4,
svm->vmcb01.ptr->save.efer,
svm->nested.ctl.nested_cr3);
vcpu->arch.mmu->get_guest_pgd = nested_svm_get_tdp_cr3;
vcpu->arch.mmu->get_pdptr = nested_svm_get_tdp_pdptr;
vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit;
vcpu->arch.walk_mmu = &vcpu->arch.nested_mmu;
}
static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)
{
vcpu->arch.mmu = &vcpu->arch.root_mmu;
vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;
}
static bool nested_vmcb_needs_vls_intercept(struct vcpu_svm *svm)
{
if (!guest_can_use(&svm->vcpu, X86_FEATURE_V_VMSAVE_VMLOAD))
return true;
if (!nested_npt_enabled(svm))
return true;
if (!(svm->nested.ctl.virt_ext & VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK))
return true;
return false;
}
void recalc_intercepts(struct vcpu_svm *svm)
{
struct vmcb_control_area *c, *h;
struct vmcb_ctrl_area_cached *g;
unsigned int i;
vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
if (!is_guest_mode(&svm->vcpu))
return;
c = &svm->vmcb->control;
h = &svm->vmcb01.ptr->control;
g = &svm->nested.ctl;
for (i = 0; i < MAX_INTERCEPT; i++)
c->intercepts[i] = h->intercepts[i];
if (g->int_ctl & V_INTR_MASKING_MASK) {
/*
* If L2 is active and V_INTR_MASKING is enabled in vmcb12,
* disable intercept of CR8 writes as L2's CR8 does not affect
* any interrupt KVM may want to inject.
*
* Similarly, disable intercept of virtual interrupts (used to
* detect interrupt windows) if the saved RFLAGS.IF is '0', as
* the effective RFLAGS.IF for L1 interrupts will never be set
* while L2 is running (L2's RFLAGS.IF doesn't affect L1 IRQs).
*/
vmcb_clr_intercept(c, INTERCEPT_CR8_WRITE);
if (!(svm->vmcb01.ptr->save.rflags & X86_EFLAGS_IF))
vmcb_clr_intercept(c, INTERCEPT_VINTR);
}
/*
* We want to see VMMCALLs from a nested guest only when Hyper-V L2 TLB
* flush feature is enabled.
*/
if (!nested_svm_l2_tlb_flush_enabled(&svm->vcpu))
vmcb_clr_intercept(c, INTERCEPT_VMMCALL);
for (i = 0; i < MAX_INTERCEPT; i++)
c->intercepts[i] |= g->intercepts[i];
/* If SMI is not intercepted, ignore guest SMI intercept as well */
if (!intercept_smi)
vmcb_clr_intercept(c, INTERCEPT_SMI);
if (nested_vmcb_needs_vls_intercept(svm)) {
/*
* If the virtual VMLOAD/VMSAVE is not enabled for the L2,
* we must intercept these instructions to correctly
* emulate them in case L1 doesn't intercept them.
*/
vmcb_set_intercept(c, INTERCEPT_VMLOAD);
vmcb_set_intercept(c, INTERCEPT_VMSAVE);
} else {
WARN_ON(!(c->virt_ext & VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK));
}
}
/*
* Merge L0's (KVM) and L1's (Nested VMCB) MSR permission bitmaps. The function
* is optimized in that it only merges the parts where KVM MSR permission bitmap
* may contain zero bits.
*/
static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
{
int i;
/*
* MSR bitmap update can be skipped when:
* - MSR bitmap for L1 hasn't changed.
* - Nested hypervisor (L1) is attempting to launch the same L2 as
* before.
* - Nested hypervisor (L1) is using Hyper-V emulation interface and
* tells KVM (L0) there were no changes in MSR bitmap for L2.
*/
#ifdef CONFIG_KVM_HYPERV
if (!svm->nested.force_msr_bitmap_recalc) {
struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
if (kvm_hv_hypercall_enabled(&svm->vcpu) &&
hve->hv_enlightenments_control.msr_bitmap &&
(svm->nested.ctl.clean & BIT(HV_VMCB_NESTED_ENLIGHTENMENTS)))
goto set_msrpm_base_pa;
}
#endif
if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
return true;
for (i = 0; i < MSRPM_OFFSETS; i++) {
u32 value, p;
u64 offset;
if (msrpm_offsets[i] == 0xffffffff)
break;
p = msrpm_offsets[i];
/* x2apic msrs are intercepted always for the nested guest */
if (is_x2apic_msrpm_offset(p))
continue;
offset = svm->nested.ctl.msrpm_base_pa + (p * 4);
if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4))
return false;
svm->nested.msrpm[p] = svm->msrpm[p] | value;
}
svm->nested.force_msr_bitmap_recalc = false;
#ifdef CONFIG_KVM_HYPERV
set_msrpm_base_pa:
#endif
svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm));
return true;
}
/*
* Bits 11:0 of bitmap address are ignored by hardware
*/
static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size)
{
u64 addr = PAGE_ALIGN(pa);
return kvm_vcpu_is_legal_gpa(vcpu, addr) &&
kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1);
}
static bool __nested_vmcb_check_controls(struct kvm_vcpu *vcpu,
struct vmcb_ctrl_area_cached *control)
{
if (CC(!vmcb12_is_intercept(control, INTERCEPT_VMRUN)))
return false;
if (CC(control->asid == 0))
return false;
if (CC((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && !npt_enabled))
return false;
if (CC(!nested_svm_check_bitmap_pa(vcpu, control->msrpm_base_pa,
MSRPM_SIZE)))
return false;
if (CC(!nested_svm_check_bitmap_pa(vcpu, control->iopm_base_pa,
IOPM_SIZE)))
return false;
if (CC((control->int_ctl & V_NMI_ENABLE_MASK) &&
!vmcb12_is_intercept(control, INTERCEPT_NMI))) {
return false;
}
return true;
}
/* Common checks that apply to both L1 and L2 state. */
static bool __nested_vmcb_check_save(struct kvm_vcpu *vcpu,
struct vmcb_save_area_cached *save)
{
if (CC(!(save->efer & EFER_SVME)))
return false;
if (CC((save->cr0 & X86_CR0_CD) == 0 && (save->cr0 & X86_CR0_NW)) ||
CC(save->cr0 & ~0xffffffffULL))
return false;
if (CC(!kvm_dr6_valid(save->dr6)) || CC(!kvm_dr7_valid(save->dr7)))
return false;
/*
* These checks are also performed by KVM_SET_SREGS,
* except that EFER.LMA is not checked by SVM against
* CR0.PG && EFER.LME.
*/
if ((save->efer & EFER_LME) && (save->cr0 & X86_CR0_PG)) {
if (CC(!(save->cr4 & X86_CR4_PAE)) ||
CC(!(save->cr0 & X86_CR0_PE)) ||
CC(!kvm_vcpu_is_legal_cr3(vcpu, save->cr3)))
return false;
}
/* Note, SVM doesn't have any additional restrictions on CR4. */
if (CC(!__kvm_is_valid_cr4(vcpu, save->cr4)))
return false;
if (CC(!kvm_valid_efer(vcpu, save->efer)))
return false;
return true;
}
static bool nested_vmcb_check_save(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb_save_area_cached *save = &svm->nested.save;
return __nested_vmcb_check_save(vcpu, save);
}
static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb_ctrl_area_cached *ctl = &svm->nested.ctl;
return __nested_vmcb_check_controls(vcpu, ctl);
}
static
void __nested_copy_vmcb_control_to_cache(struct kvm_vcpu *vcpu,
struct vmcb_ctrl_area_cached *to,
struct vmcb_control_area *from)
{
unsigned int i;
for (i = 0; i < MAX_INTERCEPT; i++)
to->intercepts[i] = from->intercepts[i];
to->iopm_base_pa = from->iopm_base_pa;
to->msrpm_base_pa = from->msrpm_base_pa;
to->tsc_offset = from->tsc_offset;
to->tlb_ctl = from->tlb_ctl;
to->int_ctl = from->int_ctl;
to->int_vector = from->int_vector;
to->int_state = from->int_state;
to->exit_code = from->exit_code;
to->exit_code_hi = from->exit_code_hi;
to->exit_info_1 = from->exit_info_1;
to->exit_info_2 = from->exit_info_2;
to->exit_int_info = from->exit_int_info;
to->exit_int_info_err = from->exit_int_info_err;
to->nested_ctl = from->nested_ctl;
to->event_inj = from->event_inj;
to->event_inj_err = from->event_inj_err;
to->next_rip = from->next_rip;
to->nested_cr3 = from->nested_cr3;
to->virt_ext = from->virt_ext;
to->pause_filter_count = from->pause_filter_count;
to->pause_filter_thresh = from->pause_filter_thresh;
/* Copy asid here because nested_vmcb_check_controls will check it. */
to->asid = from->asid;
to->msrpm_base_pa &= ~0x0fffULL;
to->iopm_base_pa &= ~0x0fffULL;
#ifdef CONFIG_KVM_HYPERV
/* Hyper-V extensions (Enlightened VMCB) */
if (kvm_hv_hypercall_enabled(vcpu)) {
to->clean = from->clean;
memcpy(&to->hv_enlightenments, &from->hv_enlightenments,
sizeof(to->hv_enlightenments));
}
#endif
}
void nested_copy_vmcb_control_to_cache(struct vcpu_svm *svm,
struct vmcb_control_area *control)
{
__nested_copy_vmcb_control_to_cache(&svm->vcpu, &svm->nested.ctl, control);
}
static void __nested_copy_vmcb_save_to_cache(struct vmcb_save_area_cached *to,
struct vmcb_save_area *from)
{
/*
* Copy only fields that are validated, as we need them
* to avoid TOC/TOU races.
*/
to->efer = from->efer;
to->cr0 = from->cr0;
to->cr3 = from->cr3;
to->cr4 = from->cr4;
to->dr6 = from->dr6;
to->dr7 = from->dr7;
}
void nested_copy_vmcb_save_to_cache(struct vcpu_svm *svm,
struct vmcb_save_area *save)
{
__nested_copy_vmcb_save_to_cache(&svm->nested.save, save);
}
/*
* Synchronize fields that are written by the processor, so that
* they can be copied back into the vmcb12.
*/
void nested_sync_control_from_vmcb02(struct vcpu_svm *svm)
{
u32 mask;
svm->nested.ctl.event_inj = svm->vmcb->control.event_inj;
svm->nested.ctl.event_inj_err = svm->vmcb->control.event_inj_err;
/* Only a few fields of int_ctl are written by the processor. */
mask = V_IRQ_MASK | V_TPR_MASK;
/*
* Don't sync vmcb02 V_IRQ back to vmcb12 if KVM (L0) is intercepting
* virtual interrupts in order to request an interrupt window, as KVM
* has usurped vmcb02's int_ctl. If an interrupt window opens before
* the next VM-Exit, svm_clear_vintr() will restore vmcb12's int_ctl.
* If no window opens, V_IRQ will be correctly preserved in vmcb12's
* int_ctl (because it was never recognized while L2 was running).
*/
if (svm_is_intercept(svm, INTERCEPT_VINTR) &&
!test_bit(INTERCEPT_VINTR, (unsigned long *)svm->nested.ctl.intercepts))
mask &= ~V_IRQ_MASK;
if (nested_vgif_enabled(svm))
mask |= V_GIF_MASK;
if (nested_vnmi_enabled(svm))
mask |= V_NMI_BLOCKING_MASK | V_NMI_PENDING_MASK;
svm->nested.ctl.int_ctl &= ~mask;
svm->nested.ctl.int_ctl |= svm->vmcb->control.int_ctl & mask;
}
/*
* Transfer any event that L0 or L1 wanted to inject into L2 to
* EXIT_INT_INFO.
*/
static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm,
struct vmcb *vmcb12)
{
struct kvm_vcpu *vcpu = &svm->vcpu;
u32 exit_int_info = 0;
unsigned int nr;
if (vcpu->arch.exception.injected) {
nr = vcpu->arch.exception.vector;
exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT;
if (vcpu->arch.exception.has_error_code) {
exit_int_info |= SVM_EVTINJ_VALID_ERR;
vmcb12->control.exit_int_info_err =
vcpu->arch.exception.error_code;
}
} else if (vcpu->arch.nmi_injected) {
exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI;
} else if (vcpu->arch.interrupt.injected) {
nr = vcpu->arch.interrupt.nr;
exit_int_info = nr | SVM_EVTINJ_VALID;
if (vcpu->arch.interrupt.soft)
exit_int_info |= SVM_EVTINJ_TYPE_SOFT;
else
exit_int_info |= SVM_EVTINJ_TYPE_INTR;
}
vmcb12->control.exit_int_info = exit_int_info;
}
static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu)
{
/* Handle pending Hyper-V TLB flush requests */
kvm_hv_nested_transtion_tlb_flush(vcpu, npt_enabled);
/*
* TODO: optimize unconditional TLB flush/MMU sync. A partial list of
* things to fix before this can be conditional:
*
* - Flush TLBs for both L1 and L2 remote TLB flush
* - Honor L1's request to flush an ASID on nested VMRUN
* - Sync nested NPT MMU on VMRUN that flushes L2's ASID[*]
* - Don't crush a pending TLB flush in vmcb02 on nested VMRUN
* - Flush L1's ASID on KVM_REQ_TLB_FLUSH_GUEST
*
* [*] Unlike nested EPT, SVM's ASID management can invalidate nested
* NPT guest-physical mappings on VMRUN.
*/
kvm_make_request(KVM_REQ_MMU_SYNC, vcpu);
kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
}
/*
* Load guest's/host's cr3 on nested vmentry or vmexit. @nested_npt is true
* if we are emulating VM-Entry into a guest with NPT enabled.
*/
static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
bool nested_npt, bool reload_pdptrs)
{
if (CC(!kvm_vcpu_is_legal_cr3(vcpu, cr3)))
return -EINVAL;
if (reload_pdptrs && !nested_npt && is_pae_paging(vcpu) &&
CC(!load_pdptrs(vcpu, cr3)))
return -EINVAL;
vcpu->arch.cr3 = cr3;
/* Re-initialize the MMU, e.g. to pick up CR4 MMU role changes. */
kvm_init_mmu(vcpu);
if (!nested_npt)
kvm_mmu_new_pgd(vcpu, cr3);
return 0;
}
void nested_vmcb02_compute_g_pat(struct vcpu_svm *svm)
{
if (!svm->nested.vmcb02.ptr)
return;
/* FIXME: merge g_pat from vmcb01 and vmcb12. */
svm->nested.vmcb02.ptr->save.g_pat = svm->vmcb01.ptr->save.g_pat;
}
static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12)
{
bool new_vmcb12 = false;
struct vmcb *vmcb01 = svm->vmcb01.ptr;
struct vmcb *vmcb02 = svm->nested.vmcb02.ptr;
struct kvm_vcpu *vcpu = &svm->vcpu;
nested_vmcb02_compute_g_pat(svm);
/* Load the nested guest state */
if (svm->nested.vmcb12_gpa != svm->nested.last_vmcb12_gpa) {
new_vmcb12 = true;
svm->nested.last_vmcb12_gpa = svm->nested.vmcb12_gpa;
svm->nested.force_msr_bitmap_recalc = true;
}
if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_SEG))) {
vmcb02->save.es = vmcb12->save.es;
vmcb02->save.cs = vmcb12->save.cs;
vmcb02->save.ss = vmcb12->save.ss;
vmcb02->save.ds = vmcb12->save.ds;
vmcb02->save.cpl = vmcb12->save.cpl;
vmcb_mark_dirty(vmcb02, VMCB_SEG);
}
if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DT))) {
vmcb02->save.gdtr = vmcb12->save.gdtr;
vmcb02->save.idtr = vmcb12->save.idtr;
vmcb_mark_dirty(vmcb02, VMCB_DT);
}
kvm_set_rflags(vcpu, vmcb12->save.rflags | X86_EFLAGS_FIXED);
svm_set_efer(vcpu, svm->nested.save.efer);
svm_set_cr0(vcpu, svm->nested.save.cr0);
svm_set_cr4(vcpu, svm->nested.save.cr4);
svm->vcpu.arch.cr2 = vmcb12->save.cr2;
kvm_rax_write(vcpu, vmcb12->save.rax);
kvm_rsp_write(vcpu, vmcb12->save.rsp);
kvm_rip_write(vcpu, vmcb12->save.rip);
/* In case we don't even reach vcpu_run, the fields are not updated */
vmcb02->save.rax = vmcb12->save.rax;
vmcb02->save.rsp = vmcb12->save.rsp;
vmcb02->save.rip = vmcb12->save.rip;
/* These bits will be set properly on the first execution when new_vmc12 is true */
if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DR))) {
vmcb02->save.dr7 = svm->nested.save.dr7 | DR7_FIXED_1;
svm->vcpu.arch.dr6 = svm->nested.save.dr6 | DR6_ACTIVE_LOW;
vmcb_mark_dirty(vmcb02, VMCB_DR);
}
if (unlikely(guest_can_use(vcpu, X86_FEATURE_LBRV) &&
(svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) {
/*
* Reserved bits of DEBUGCTL are ignored. Be consistent with
* svm_set_msr's definition of reserved bits.
*/
svm_copy_lbrs(vmcb02, vmcb12);
vmcb02->save.dbgctl &= ~DEBUGCTL_RESERVED_BITS;
svm_update_lbrv(&svm->vcpu);
} else if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) {
svm_copy_lbrs(vmcb02, vmcb01);
}
}
static inline bool is_evtinj_soft(u32 evtinj)
{
u32 type = evtinj & SVM_EVTINJ_TYPE_MASK;
u8 vector = evtinj & SVM_EVTINJ_VEC_MASK;
if (!(evtinj & SVM_EVTINJ_VALID))
return false;
if (type == SVM_EVTINJ_TYPE_SOFT)
return true;
return type == SVM_EVTINJ_TYPE_EXEPT && kvm_exception_is_soft(vector);
}
static bool is_evtinj_nmi(u32 evtinj)
{
u32 type = evtinj & SVM_EVTINJ_TYPE_MASK;
if (!(evtinj & SVM_EVTINJ_VALID))
return false;
return type == SVM_EVTINJ_TYPE_NMI;
}
static void nested_vmcb02_prepare_control(struct vcpu_svm *svm,
unsigned long vmcb12_rip,
unsigned long vmcb12_csbase)
{
u32 int_ctl_vmcb01_bits = V_INTR_MASKING_MASK;
u32 int_ctl_vmcb12_bits = V_TPR_MASK | V_IRQ_INJECTION_BITS_MASK;
struct kvm_vcpu *vcpu = &svm->vcpu;
struct vmcb *vmcb01 = svm->vmcb01.ptr;
struct vmcb *vmcb02 = svm->nested.vmcb02.ptr;
u32 pause_count12;
u32 pause_thresh12;
/*
* Filled at exit: exit_code, exit_code_hi, exit_info_1, exit_info_2,
* exit_int_info, exit_int_info_err, next_rip, insn_len, insn_bytes.
*/
if (guest_can_use(vcpu, X86_FEATURE_VGIF) &&
(svm->nested.ctl.int_ctl & V_GIF_ENABLE_MASK))
int_ctl_vmcb12_bits |= (V_GIF_MASK | V_GIF_ENABLE_MASK);
else
int_ctl_vmcb01_bits |= (V_GIF_MASK | V_GIF_ENABLE_MASK);
if (vnmi) {
if (vmcb01->control.int_ctl & V_NMI_PENDING_MASK) {
svm->vcpu.arch.nmi_pending++;
kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
}
if (nested_vnmi_enabled(svm))
int_ctl_vmcb12_bits |= (V_NMI_PENDING_MASK |
V_NMI_ENABLE_MASK |
V_NMI_BLOCKING_MASK);
}
/* Copied from vmcb01. msrpm_base can be overwritten later. */
vmcb02->control.nested_ctl = vmcb01->control.nested_ctl;
vmcb02->control.iopm_base_pa = vmcb01->control.iopm_base_pa;
vmcb02->control.msrpm_base_pa = vmcb01->control.msrpm_base_pa;
/* Done at vmrun: asid. */
/* Also overwritten later if necessary. */
vmcb02->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
/* nested_cr3. */
if (nested_npt_enabled(svm))
nested_svm_init_mmu_context(vcpu);
vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset(
vcpu->arch.l1_tsc_offset,
svm->nested.ctl.tsc_offset,
svm->tsc_ratio_msr);
vmcb02->control.tsc_offset = vcpu->arch.tsc_offset;
if (guest_can_use(vcpu, X86_FEATURE_TSCRATEMSR) &&
svm->tsc_ratio_msr != kvm_caps.default_tsc_scaling_ratio)
nested_svm_update_tsc_ratio_msr(vcpu);
vmcb02->control.int_ctl =
(svm->nested.ctl.int_ctl & int_ctl_vmcb12_bits) |
(vmcb01->control.int_ctl & int_ctl_vmcb01_bits);
vmcb02->control.int_vector = svm->nested.ctl.int_vector;
vmcb02->control.int_state = svm->nested.ctl.int_state;
vmcb02->control.event_inj = svm->nested.ctl.event_inj;
vmcb02->control.event_inj_err = svm->nested.ctl.event_inj_err;
/*
* next_rip is consumed on VMRUN as the return address pushed on the
* stack for injected soft exceptions/interrupts. If nrips is exposed
* to L1, take it verbatim from vmcb12. If nrips is supported in
* hardware but not exposed to L1, stuff the actual L2 RIP to emulate
* what a nrips=0 CPU would do (L1 is responsible for advancing RIP
* prior to injecting the event).
*/
if (guest_can_use(vcpu, X86_FEATURE_NRIPS))
vmcb02->control.next_rip = svm->nested.ctl.next_rip;
else if (boot_cpu_has(X86_FEATURE_NRIPS))
vmcb02->control.next_rip = vmcb12_rip;
svm->nmi_l1_to_l2 = is_evtinj_nmi(vmcb02->control.event_inj);
if (is_evtinj_soft(vmcb02->control.event_inj)) {
svm->soft_int_injected = true;
svm->soft_int_csbase = vmcb12_csbase;
svm->soft_int_old_rip = vmcb12_rip;
if (guest_can_use(vcpu, X86_FEATURE_NRIPS))
svm->soft_int_next_rip = svm->nested.ctl.next_rip;
else
svm->soft_int_next_rip = vmcb12_rip;
}
vmcb02->control.virt_ext = vmcb01->control.virt_ext &
LBR_CTL_ENABLE_MASK;
if (guest_can_use(vcpu, X86_FEATURE_LBRV))
vmcb02->control.virt_ext |=
(svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK);
if (!nested_vmcb_needs_vls_intercept(svm))
vmcb02->control.virt_ext |= VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK;
if (guest_can_use(vcpu, X86_FEATURE_PAUSEFILTER))
pause_count12 = svm->nested.ctl.pause_filter_count;
else
pause_count12 = 0;
if (guest_can_use(vcpu, X86_FEATURE_PFTHRESHOLD))
pause_thresh12 = svm->nested.ctl.pause_filter_thresh;
else
pause_thresh12 = 0;
if (kvm_pause_in_guest(svm->vcpu.kvm)) {
/* use guest values since host doesn't intercept PAUSE */
vmcb02->control.pause_filter_count = pause_count12;
vmcb02->control.pause_filter_thresh = pause_thresh12;
} else {
/* start from host values otherwise */
vmcb02->control.pause_filter_count = vmcb01->control.pause_filter_count;
vmcb02->control.pause_filter_thresh = vmcb01->control.pause_filter_thresh;
/* ... but ensure filtering is disabled if so requested. */
if (vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_PAUSE)) {
if (!pause_count12)
vmcb02->control.pause_filter_count = 0;
if (!pause_thresh12)
vmcb02->control.pause_filter_thresh = 0;
}
}
nested_svm_transition_tlb_flush(vcpu);
/* Enter Guest-Mode */
enter_guest_mode(vcpu);
/*
* Merge guest and host intercepts - must be called with vcpu in
* guest-mode to take effect.
*/
recalc_intercepts(svm);
}
static void nested_svm_copy_common_state(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
{
/*
* Some VMCB state is shared between L1 and L2 and thus has to be
* moved at the time of nested vmrun and vmexit.
*
* VMLOAD/VMSAVE state would also belong in this category, but KVM
* always performs VMLOAD and VMSAVE from the VMCB01.
*/
to_vmcb->save.spec_ctrl = from_vmcb->save.spec_ctrl;
}
int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa,
struct vmcb *vmcb12, bool from_vmrun)
{
struct vcpu_svm *svm = to_svm(vcpu);
int ret;
trace_kvm_nested_vmenter(svm->vmcb->save.rip,
vmcb12_gpa,
vmcb12->save.rip,
vmcb12->control.int_ctl,
vmcb12->control.event_inj,
vmcb12->control.nested_ctl,
vmcb12->control.nested_cr3,
vmcb12->save.cr3,
KVM_ISA_SVM);
trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff,
vmcb12->control.intercepts[INTERCEPT_CR] >> 16,
vmcb12->control.intercepts[INTERCEPT_EXCEPTION],
vmcb12->control.intercepts[INTERCEPT_WORD3],
vmcb12->control.intercepts[INTERCEPT_WORD4],
vmcb12->control.intercepts[INTERCEPT_WORD5]);
svm->nested.vmcb12_gpa = vmcb12_gpa;
WARN_ON(svm->vmcb == svm->nested.vmcb02.ptr);
nested_svm_copy_common_state(svm->vmcb01.ptr, svm->nested.vmcb02.ptr);
svm_switch_vmcb(svm, &svm->nested.vmcb02);
nested_vmcb02_prepare_control(svm, vmcb12->save.rip, vmcb12->save.cs.base);
nested_vmcb02_prepare_save(svm, vmcb12);
ret = nested_svm_load_cr3(&svm->vcpu, svm->nested.save.cr3,
nested_npt_enabled(svm), from_vmrun);
if (ret)
return ret;
if (!from_vmrun)
kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
svm_set_gif(svm, true);
if (kvm_vcpu_apicv_active(vcpu))
kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
nested_svm_hv_update_vm_vp_ids(vcpu);
return 0;
}
int nested_svm_vmrun(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
int ret;
struct vmcb *vmcb12;
struct kvm_host_map map;
u64 vmcb12_gpa;
struct vmcb *vmcb01 = svm->vmcb01.ptr;
if (!svm->nested.hsave_msr) {
kvm_inject_gp(vcpu, 0);
return 1;
}
if (is_smm(vcpu)) {
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
/* This fails when VP assist page is enabled but the supplied GPA is bogus */
ret = kvm_hv_verify_vp_assist(vcpu);
if (ret) {
kvm_inject_gp(vcpu, 0);
return ret;
}
vmcb12_gpa = svm->vmcb->save.rax;
ret = kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map);
if (ret == -EINVAL) {
kvm_inject_gp(vcpu, 0);
return 1;
} else if (ret) {
return kvm_skip_emulated_instruction(vcpu);
}
ret = kvm_skip_emulated_instruction(vcpu);
vmcb12 = map.hva;
if (WARN_ON_ONCE(!svm->nested.initialized))
return -EINVAL;
nested_copy_vmcb_control_to_cache(svm, &vmcb12->control);
nested_copy_vmcb_save_to_cache(svm, &vmcb12->save);
if (!nested_vmcb_check_save(vcpu) ||
!nested_vmcb_check_controls(vcpu)) {
vmcb12->control.exit_code = SVM_EXIT_ERR;
vmcb12->control.exit_code_hi = 0;
vmcb12->control.exit_info_1 = 0;
vmcb12->control.exit_info_2 = 0;
goto out;
}
/*
* Since vmcb01 is not in use, we can use it to store some of the L1
* state.
*/
vmcb01->save.efer = vcpu->arch.efer;
vmcb01->save.cr0 = kvm_read_cr0(vcpu);
vmcb01->save.cr4 = vcpu->arch.cr4;
vmcb01->save.rflags = kvm_get_rflags(vcpu);
vmcb01->save.rip = kvm_rip_read(vcpu);
if (!npt_enabled)
vmcb01->save.cr3 = kvm_read_cr3(vcpu);
svm->nested.nested_run_pending = 1;
if (enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12, true))
goto out_exit_err;
if (nested_svm_vmrun_msrpm(svm))
goto out;
out_exit_err:
svm->nested.nested_run_pending = 0;
svm->nmi_l1_to_l2 = false;
svm->soft_int_injected = false;
svm->vmcb->control.exit_code = SVM_EXIT_ERR;
svm->vmcb->control.exit_code_hi = 0;
svm->vmcb->control.exit_info_1 = 0;
svm->vmcb->control.exit_info_2 = 0;
nested_svm_vmexit(svm);
out:
kvm_vcpu_unmap(vcpu, &map, true);
return ret;
}
/* Copy state save area fields which are handled by VMRUN */
void svm_copy_vmrun_state(struct vmcb_save_area *to_save,
struct vmcb_save_area *from_save)
{
to_save->es = from_save->es;
to_save->cs = from_save->cs;
to_save->ss = from_save->ss;
to_save->ds = from_save->ds;
to_save->gdtr = from_save->gdtr;
to_save->idtr = from_save->idtr;
to_save->rflags = from_save->rflags | X86_EFLAGS_FIXED;
to_save->efer = from_save->efer;
to_save->cr0 = from_save->cr0;
to_save->cr3 = from_save->cr3;
to_save->cr4 = from_save->cr4;
to_save->rax = from_save->rax;
to_save->rsp = from_save->rsp;
to_save->rip = from_save->rip;
to_save->cpl = 0;
}
void svm_copy_vmloadsave_state(struct vmcb *to_vmcb, struct vmcb *from_vmcb)
{
to_vmcb->save.fs = from_vmcb->save.fs;
to_vmcb->save.gs = from_vmcb->save.gs;
to_vmcb->save.tr = from_vmcb->save.tr;
to_vmcb->save.ldtr = from_vmcb->save.ldtr;
to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
to_vmcb->save.star = from_vmcb->save.star;
to_vmcb->save.lstar = from_vmcb->save.lstar;
to_vmcb->save.cstar = from_vmcb->save.cstar;
to_vmcb->save.sfmask = from_vmcb->save.sfmask;
to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
}
int nested_svm_vmexit(struct vcpu_svm *svm)
{
struct kvm_vcpu *vcpu = &svm->vcpu;
struct vmcb *vmcb01 = svm->vmcb01.ptr;
struct vmcb *vmcb02 = svm->nested.vmcb02.ptr;
struct vmcb *vmcb12;
struct kvm_host_map map;
int rc;
rc = kvm_vcpu_map(vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map);
if (rc) {
if (rc == -EINVAL)
kvm_inject_gp(vcpu, 0);
return 1;
}
vmcb12 = map.hva;
/* Exit Guest-Mode */
leave_guest_mode(vcpu);
svm->nested.vmcb12_gpa = 0;
WARN_ON_ONCE(svm->nested.nested_run_pending);
kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
/* in case we halted in L2 */
svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE;
/* Give the current vmcb to the guest */
vmcb12->save.es = vmcb02->save.es;
vmcb12->save.cs = vmcb02->save.cs;
vmcb12->save.ss = vmcb02->save.ss;
vmcb12->save.ds = vmcb02->save.ds;
vmcb12->save.gdtr = vmcb02->save.gdtr;
vmcb12->save.idtr = vmcb02->save.idtr;
vmcb12->save.efer = svm->vcpu.arch.efer;
vmcb12->save.cr0 = kvm_read_cr0(vcpu);
vmcb12->save.cr3 = kvm_read_cr3(vcpu);
vmcb12->save.cr2 = vmcb02->save.cr2;
vmcb12->save.cr4 = svm->vcpu.arch.cr4;
vmcb12->save.rflags = kvm_get_rflags(vcpu);
vmcb12->save.rip = kvm_rip_read(vcpu);
vmcb12->save.rsp = kvm_rsp_read(vcpu);
vmcb12->save.rax = kvm_rax_read(vcpu);
vmcb12->save.dr7 = vmcb02->save.dr7;
vmcb12->save.dr6 = svm->vcpu.arch.dr6;
vmcb12->save.cpl = vmcb02->save.cpl;
vmcb12->control.int_state = vmcb02->control.int_state;
vmcb12->control.exit_code = vmcb02->control.exit_code;
vmcb12->control.exit_code_hi = vmcb02->control.exit_code_hi;
vmcb12->control.exit_info_1 = vmcb02->control.exit_info_1;
vmcb12->control.exit_info_2 = vmcb02->control.exit_info_2;
if (vmcb12->control.exit_code != SVM_EXIT_ERR)
nested_save_pending_event_to_vmcb12(svm, vmcb12);
if (guest_can_use(vcpu, X86_FEATURE_NRIPS))
vmcb12->control.next_rip = vmcb02->control.next_rip;
vmcb12->control.int_ctl = svm->nested.ctl.int_ctl;
vmcb12->control.event_inj = svm->nested.ctl.event_inj;
vmcb12->control.event_inj_err = svm->nested.ctl.event_inj_err;
if (!kvm_pause_in_guest(vcpu->kvm)) {
vmcb01->control.pause_filter_count = vmcb02->control.pause_filter_count;
vmcb_mark_dirty(vmcb01, VMCB_INTERCEPTS);
}
nested_svm_copy_common_state(svm->nested.vmcb02.ptr, svm->vmcb01.ptr);
svm_switch_vmcb(svm, &svm->vmcb01);
/*
* Rules for synchronizing int_ctl bits from vmcb02 to vmcb01:
*
* V_IRQ, V_IRQ_VECTOR, V_INTR_PRIO_MASK, V_IGN_TPR: If L1 doesn't
* intercept interrupts, then KVM will use vmcb02's V_IRQ (and related
* flags) to detect interrupt windows for L1 IRQs (even if L1 uses
* virtual interrupt masking). Raise KVM_REQ_EVENT to ensure that
* KVM re-requests an interrupt window if necessary, which implicitly
* copies this bits from vmcb02 to vmcb01.
*
* V_TPR: If L1 doesn't use virtual interrupt masking, then L1's vTPR
* is stored in vmcb02, but its value doesn't need to be copied from/to
* vmcb01 because it is copied from/to the virtual APIC's TPR register
* on each VM entry/exit.
*
* V_GIF: If nested vGIF is not used, KVM uses vmcb02's V_GIF for L1's
* V_GIF. However, GIF is architecturally clear on each VM exit, thus
* there is no need to copy V_GIF from vmcb02 to vmcb01.
*/
if (!nested_exit_on_intr(svm))
kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
if (unlikely(guest_can_use(vcpu, X86_FEATURE_LBRV) &&
(svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) {
svm_copy_lbrs(vmcb12, vmcb02);
svm_update_lbrv(vcpu);
} else if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) {
svm_copy_lbrs(vmcb01, vmcb02);
svm_update_lbrv(vcpu);
}
if (vnmi) {
if (vmcb02->control.int_ctl & V_NMI_BLOCKING_MASK)
vmcb01->control.int_ctl |= V_NMI_BLOCKING_MASK;
else
vmcb01->control.int_ctl &= ~V_NMI_BLOCKING_MASK;
if (vcpu->arch.nmi_pending) {
vcpu->arch.nmi_pending--;
vmcb01->control.int_ctl |= V_NMI_PENDING_MASK;
} else {
vmcb01->control.int_ctl &= ~V_NMI_PENDING_MASK;
}
}
/*
* On vmexit the GIF is set to false and
* no event can be injected in L1.
*/
svm_set_gif(svm, false);
vmcb01->control.exit_int_info = 0;
svm->vcpu.arch.tsc_offset = svm->vcpu.arch.l1_tsc_offset;
if (vmcb01->control.tsc_offset != svm->vcpu.arch.tsc_offset) {
vmcb01->control.tsc_offset = svm->vcpu.arch.tsc_offset;
vmcb_mark_dirty(vmcb01, VMCB_INTERCEPTS);
}
if (kvm_caps.has_tsc_control &&
vcpu->arch.tsc_scaling_ratio != vcpu->arch.l1_tsc_scaling_ratio) {
vcpu->arch.tsc_scaling_ratio = vcpu->arch.l1_tsc_scaling_ratio;
svm_write_tsc_multiplier(vcpu);
}
svm->nested.ctl.nested_cr3 = 0;
/*
* Restore processor state that had been saved in vmcb01
*/
kvm_set_rflags(vcpu, vmcb01->save.rflags);
svm_set_efer(vcpu, vmcb01->save.efer);
svm_set_cr0(vcpu, vmcb01->save.cr0 | X86_CR0_PE);
svm_set_cr4(vcpu, vmcb01->save.cr4);
kvm_rax_write(vcpu, vmcb01->save.rax);
kvm_rsp_write(vcpu, vmcb01->save.rsp);
kvm_rip_write(vcpu, vmcb01->save.rip);
svm->vcpu.arch.dr7 = DR7_FIXED_1;
kvm_update_dr7(&svm->vcpu);
trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code,
vmcb12->control.exit_info_1,
vmcb12->control.exit_info_2,
vmcb12->control.exit_int_info,
vmcb12->control.exit_int_info_err,
KVM_ISA_SVM);
kvm_vcpu_unmap(vcpu, &map, true);
nested_svm_transition_tlb_flush(vcpu);
nested_svm_uninit_mmu_context(vcpu);
rc = nested_svm_load_cr3(vcpu, vmcb01->save.cr3, false, true);
if (rc)
return 1;
/*
* Drop what we picked up for L2 via svm_complete_interrupts() so it
* doesn't end up in L1.
*/
svm->vcpu.arch.nmi_injected = false;
kvm_clear_exception_queue(vcpu);
kvm_clear_interrupt_queue(vcpu);
/*
* If we are here following the completion of a VMRUN that
* is being single-stepped, queue the pending #DB intercept
* right now so that it an be accounted for before we execute
* L1's next instruction.
*/
if (unlikely(vmcb01->save.rflags & X86_EFLAGS_TF))
kvm_queue_exception(&(svm->vcpu), DB_VECTOR);
/*
* Un-inhibit the AVIC right away, so that other vCPUs can start
* to benefit from it right away.
*/
if (kvm_apicv_activated(vcpu->kvm))
__kvm_vcpu_update_apicv(vcpu);
return 0;
}
static void nested_svm_triple_fault(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
if (!vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_SHUTDOWN))
return;
kvm_clear_request(KVM_REQ_TRIPLE_FAULT, vcpu);
nested_svm_simple_vmexit(to_svm(vcpu), SVM_EXIT_SHUTDOWN);
}
int svm_allocate_nested(struct vcpu_svm *svm)
{
struct page *vmcb02_page;
if (svm->nested.initialized)
return 0;
vmcb02_page = snp_safe_alloc_page();
if (!vmcb02_page)
return -ENOMEM;
svm->nested.vmcb02.ptr = page_address(vmcb02_page);
svm->nested.vmcb02.pa = __sme_set(page_to_pfn(vmcb02_page) << PAGE_SHIFT);
svm->nested.msrpm = svm_vcpu_alloc_msrpm();
if (!svm->nested.msrpm)
goto err_free_vmcb02;
svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm);
svm->nested.initialized = true;
return 0;
err_free_vmcb02:
__free_page(vmcb02_page);
return -ENOMEM;
}
void svm_free_nested(struct vcpu_svm *svm)
{
if (!svm->nested.initialized)
return;
if (WARN_ON_ONCE(svm->vmcb != svm->vmcb01.ptr))
svm_switch_vmcb(svm, &svm->vmcb01);
svm_vcpu_free_msrpm(svm->nested.msrpm);
svm->nested.msrpm = NULL;
__free_page(virt_to_page(svm->nested.vmcb02.ptr));
svm->nested.vmcb02.ptr = NULL;
/*
* When last_vmcb12_gpa matches the current vmcb12 gpa,
* some vmcb12 fields are not loaded if they are marked clean
* in the vmcb12, since in this case they are up to date already.
*
* When the vmcb02 is freed, this optimization becomes invalid.
*/
svm->nested.last_vmcb12_gpa = INVALID_GPA;
svm->nested.initialized = false;
}
void svm_leave_nested(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
if (is_guest_mode(vcpu)) {
svm->nested.nested_run_pending = 0;
svm->nested.vmcb12_gpa = INVALID_GPA;
leave_guest_mode(vcpu);
svm_switch_vmcb(svm, &svm->vmcb01);
nested_svm_uninit_mmu_context(vcpu);
vmcb_mark_all_dirty(svm->vmcb);
if (kvm_apicv_activated(vcpu->kvm))
kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
}
kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
}
static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
{
u32 offset, msr, value;
int write, mask;
if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
return NESTED_EXIT_HOST;
msr = svm->vcpu.arch.regs[VCPU_REGS_RCX];
offset = svm_msrpm_offset(msr);
write = svm->vmcb->control.exit_info_1 & 1;
mask = 1 << ((2 * (msr & 0xf)) + write);
if (offset == MSR_INVALID)
return NESTED_EXIT_DONE;
/* Offset is in 32 bit units but need in 8 bit units */
offset *= 4;
if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4))
return NESTED_EXIT_DONE;
return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
}
static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
{
unsigned port, size, iopm_len;
u16 val, mask;
u8 start_bit;
u64 gpa;
if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
return NESTED_EXIT_HOST;
port = svm->vmcb->control.exit_info_1 >> 16;
size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >>
SVM_IOIO_SIZE_SHIFT;
gpa = svm->nested.ctl.iopm_base_pa + (port / 8);
start_bit = port % 8;
iopm_len = (start_bit + size > 8) ? 2 : 1;
mask = (0xf >> (4 - size)) << start_bit;
val = 0;
if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len))
return NESTED_EXIT_DONE;
return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
}
static int nested_svm_intercept(struct vcpu_svm *svm)
{
u32 exit_code = svm->vmcb->control.exit_code;
int vmexit = NESTED_EXIT_HOST;
switch (exit_code) {
case SVM_EXIT_MSR:
vmexit = nested_svm_exit_handled_msr(svm);
break;
case SVM_EXIT_IOIO:
vmexit = nested_svm_intercept_ioio(svm);
break;
case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
vmexit = NESTED_EXIT_DONE;
break;
}
case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
vmexit = NESTED_EXIT_DONE;
break;
}
case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
/*
* Host-intercepted exceptions have been checked already in
* nested_svm_exit_special. There is nothing to do here,
* the vmexit is injected by svm_check_nested_events.
*/
vmexit = NESTED_EXIT_DONE;
break;
}
case SVM_EXIT_ERR: {
vmexit = NESTED_EXIT_DONE;
break;
}
default: {
if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
vmexit = NESTED_EXIT_DONE;
}
}
return vmexit;
}
int nested_svm_exit_handled(struct vcpu_svm *svm)
{
int vmexit;
vmexit = nested_svm_intercept(svm);
if (vmexit == NESTED_EXIT_DONE)
nested_svm_vmexit(svm);
return vmexit;
}
int nested_svm_check_permissions(struct kvm_vcpu *vcpu)
{
if (!(vcpu->arch.efer & EFER_SVME) || !is_paging(vcpu)) {
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
if (to_svm(vcpu)->vmcb->save.cpl) {
kvm_inject_gp(vcpu, 0);
return 1;
}
return 0;
}
static bool nested_svm_is_exception_vmexit(struct kvm_vcpu *vcpu, u8 vector,
u32 error_code)
{
struct vcpu_svm *svm = to_svm(vcpu);
return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(vector));
}
static void nested_svm_inject_exception_vmexit(struct kvm_vcpu *vcpu)
{
struct kvm_queued_exception *ex = &vcpu->arch.exception_vmexit;
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb *vmcb = svm->vmcb;
vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + ex->vector;
vmcb->control.exit_code_hi = 0;
if (ex->has_error_code)
vmcb->control.exit_info_1 = ex->error_code;
/*
* EXITINFO2 is undefined for all exception intercepts other
* than #PF.
*/
if (ex->vector == PF_VECTOR) {
if (ex->has_payload)
vmcb->control.exit_info_2 = ex->payload;
else
vmcb->control.exit_info_2 = vcpu->arch.cr2;
} else if (ex->vector == DB_VECTOR) {
/* See kvm_check_and_inject_events(). */
kvm_deliver_exception_payload(vcpu, ex);
if (vcpu->arch.dr7 & DR7_GD) {
vcpu->arch.dr7 &= ~DR7_GD;
kvm_update_dr7(vcpu);
}
} else {
WARN_ON(ex->has_payload);
}
nested_svm_vmexit(svm);
}
static inline bool nested_exit_on_init(struct vcpu_svm *svm)
{
return vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
}
static int svm_check_nested_events(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
struct vcpu_svm *svm = to_svm(vcpu);
/*
* Only a pending nested run blocks a pending exception. If there is a
* previously injected event, the pending exception occurred while said
* event was being delivered and thus needs to be handled.
*/
bool block_nested_exceptions = svm->nested.nested_run_pending;
/*
* New events (not exceptions) are only recognized at instruction
* boundaries. If an event needs reinjection, then KVM is handling a
* VM-Exit that occurred _during_ instruction execution; new events are
* blocked until the instruction completes.
*/
bool block_nested_events = block_nested_exceptions ||
kvm_event_needs_reinjection(vcpu);
if (lapic_in_kernel(vcpu) &&
test_bit(KVM_APIC_INIT, &apic->pending_events)) {
if (block_nested_events)
return -EBUSY;
if (!nested_exit_on_init(svm))
return 0;
nested_svm_simple_vmexit(svm, SVM_EXIT_INIT);
return 0;
}
if (vcpu->arch.exception_vmexit.pending) {
if (block_nested_exceptions)
return -EBUSY;
nested_svm_inject_exception_vmexit(vcpu);
return 0;
}
if (vcpu->arch.exception.pending) {
if (block_nested_exceptions)
return -EBUSY;
return 0;
}
#ifdef CONFIG_KVM_SMM
if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
if (block_nested_events)
return -EBUSY;
if (!nested_exit_on_smi(svm))
return 0;
nested_svm_simple_vmexit(svm, SVM_EXIT_SMI);
return 0;
}
#endif
if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
if (block_nested_events)
return -EBUSY;
if (!nested_exit_on_nmi(svm))
return 0;
nested_svm_simple_vmexit(svm, SVM_EXIT_NMI);
return 0;
}
if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
if (block_nested_events)
return -EBUSY;
if (!nested_exit_on_intr(svm))
return 0;
trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
nested_svm_simple_vmexit(svm, SVM_EXIT_INTR);
return 0;
}
return 0;
}
int nested_svm_exit_special(struct vcpu_svm *svm)
{
u32 exit_code = svm->vmcb->control.exit_code;
struct kvm_vcpu *vcpu = &svm->vcpu;
switch (exit_code) {
case SVM_EXIT_INTR:
case SVM_EXIT_NMI:
case SVM_EXIT_NPF:
return NESTED_EXIT_HOST;
case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
if (svm->vmcb01.ptr->control.intercepts[INTERCEPT_EXCEPTION] &
excp_bits)
return NESTED_EXIT_HOST;
else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR &&
svm->vcpu.arch.apf.host_apf_flags)
/* Trap async PF even if not shadowing */
return NESTED_EXIT_HOST;
break;
}
case SVM_EXIT_VMMCALL:
/* Hyper-V L2 TLB flush hypercall is handled by L0 */
if (guest_hv_cpuid_has_l2_tlb_flush(vcpu) &&
nested_svm_l2_tlb_flush_enabled(vcpu) &&
kvm_hv_is_tlb_flush_hcall(vcpu))
return NESTED_EXIT_HOST;
break;
default:
break;
}
return NESTED_EXIT_CONTINUE;
}
void nested_svm_update_tsc_ratio_msr(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
vcpu->arch.tsc_scaling_ratio =
kvm_calc_nested_tsc_multiplier(vcpu->arch.l1_tsc_scaling_ratio,
svm->tsc_ratio_msr);
svm_write_tsc_multiplier(vcpu);
}
/* Inverse operation of nested_copy_vmcb_control_to_cache(). asid is copied too. */
static void nested_copy_vmcb_cache_to_control(struct vmcb_control_area *dst,
struct vmcb_ctrl_area_cached *from)
{
unsigned int i;
memset(dst, 0, sizeof(struct vmcb_control_area));
for (i = 0; i < MAX_INTERCEPT; i++)
dst->intercepts[i] = from->intercepts[i];
dst->iopm_base_pa = from->iopm_base_pa;
dst->msrpm_base_pa = from->msrpm_base_pa;
dst->tsc_offset = from->tsc_offset;
dst->asid = from->asid;
dst->tlb_ctl = from->tlb_ctl;
dst->int_ctl = from->int_ctl;
dst->int_vector = from->int_vector;
dst->int_state = from->int_state;
dst->exit_code = from->exit_code;
dst->exit_code_hi = from->exit_code_hi;
dst->exit_info_1 = from->exit_info_1;
dst->exit_info_2 = from->exit_info_2;
dst->exit_int_info = from->exit_int_info;
dst->exit_int_info_err = from->exit_int_info_err;
dst->nested_ctl = from->nested_ctl;
dst->event_inj = from->event_inj;
dst->event_inj_err = from->event_inj_err;
dst->next_rip = from->next_rip;
dst->nested_cr3 = from->nested_cr3;
dst->virt_ext = from->virt_ext;
dst->pause_filter_count = from->pause_filter_count;
dst->pause_filter_thresh = from->pause_filter_thresh;
/* 'clean' and 'hv_enlightenments' are not changed by KVM */
}
static int svm_get_nested_state(struct kvm_vcpu *vcpu,
struct kvm_nested_state __user *user_kvm_nested_state,
u32 user_data_size)
{
struct vcpu_svm *svm;
struct vmcb_control_area *ctl;
unsigned long r;
struct kvm_nested_state kvm_state = {
.flags = 0,
.format = KVM_STATE_NESTED_FORMAT_SVM,
.size = sizeof(kvm_state),
};
struct vmcb __user *user_vmcb = (struct vmcb __user *)
&user_kvm_nested_state->data.svm[0];
if (!vcpu)
return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE;
svm = to_svm(vcpu);
if (user_data_size < kvm_state.size)
goto out;
/* First fill in the header and copy it out. */
if (is_guest_mode(vcpu)) {
kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa;
kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
if (svm->nested.nested_run_pending)
kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING;
}
if (gif_set(svm))
kvm_state.flags |= KVM_STATE_NESTED_GIF_SET;
if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state)))
return -EFAULT;
if (!is_guest_mode(vcpu))
goto out;
/*
* Copy over the full size of the VMCB rather than just the size
* of the structs.
*/
if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
return -EFAULT;
ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
if (!ctl)
return -ENOMEM;
nested_copy_vmcb_cache_to_control(ctl, &svm->nested.ctl);
r = copy_to_user(&user_vmcb->control, ctl,
sizeof(user_vmcb->control));
kfree(ctl);
if (r)
return -EFAULT;
if (copy_to_user(&user_vmcb->save, &svm->vmcb01.ptr->save,
sizeof(user_vmcb->save)))
return -EFAULT;
out:
return kvm_state.size;
}
static int svm_set_nested_state(struct kvm_vcpu *vcpu,
struct kvm_nested_state __user *user_kvm_nested_state,
struct kvm_nested_state *kvm_state)
{
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb __user *user_vmcb = (struct vmcb __user *)
&user_kvm_nested_state->data.svm[0];
struct vmcb_control_area *ctl;
struct vmcb_save_area *save;
struct vmcb_save_area_cached save_cached;
struct vmcb_ctrl_area_cached ctl_cached;
unsigned long cr0;
int ret;
BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
KVM_STATE_NESTED_SVM_VMCB_SIZE);
if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
return -EINVAL;
if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE |
KVM_STATE_NESTED_RUN_PENDING |
KVM_STATE_NESTED_GIF_SET))
return -EINVAL;
/*
* If in guest mode, vcpu->arch.efer actually refers to the L2 guest's
* EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed.
*/
if (!(vcpu->arch.efer & EFER_SVME)) {
/* GIF=1 and no guest mode are required if SVME=0. */
if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET)
return -EINVAL;
}
/* SMM temporarily disables SVM, so we cannot be in guest mode. */
if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE))
return -EINVAL;
if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
svm_leave_nested(vcpu);
svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
return 0;
}
if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
return -EINVAL;
if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE)
return -EINVAL;
ret = -ENOMEM;
ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
save = kzalloc(sizeof(*save), GFP_KERNEL);
if (!ctl || !save)
goto out_free;
ret = -EFAULT;
if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl)))
goto out_free;
if (copy_from_user(save, &user_vmcb->save, sizeof(*save)))
goto out_free;
ret = -EINVAL;
__nested_copy_vmcb_control_to_cache(vcpu, &ctl_cached, ctl);
if (!__nested_vmcb_check_controls(vcpu, &ctl_cached))
goto out_free;
/*
* Processor state contains L2 state. Check that it is
* valid for guest mode (see nested_vmcb_check_save).
*/
cr0 = kvm_read_cr0(vcpu);
if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
goto out_free;
/*
* Validate host state saved from before VMRUN (see
* nested_svm_check_permissions).
*/
__nested_copy_vmcb_save_to_cache(&save_cached, save);
if (!(save->cr0 & X86_CR0_PG) ||
!(save->cr0 & X86_CR0_PE) ||
(save->rflags & X86_EFLAGS_VM) ||
!__nested_vmcb_check_save(vcpu, &save_cached))
goto out_free;
/*
* All checks done, we can enter guest mode. Userspace provides
* vmcb12.control, which will be combined with L1 and stored into
* vmcb02, and the L1 save state which we store in vmcb01.
* L2 registers if needed are moved from the current VMCB to VMCB02.
*/
if (is_guest_mode(vcpu))
svm_leave_nested(vcpu);
else
svm->nested.vmcb02.ptr->save = svm->vmcb01.ptr->save;
svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
svm->nested.nested_run_pending =
!!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);
svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;
svm_copy_vmrun_state(&svm->vmcb01.ptr->save, save);
nested_copy_vmcb_control_to_cache(svm, ctl);
svm_switch_vmcb(svm, &svm->nested.vmcb02);
nested_vmcb02_prepare_control(svm, svm->vmcb->save.rip, svm->vmcb->save.cs.base);
/*
* While the nested guest CR3 is already checked and set by
* KVM_SET_SREGS, it was set when nested state was yet loaded,
* thus MMU might not be initialized correctly.
* Set it again to fix this.
*/
ret = nested_svm_load_cr3(&svm->vcpu, vcpu->arch.cr3,
nested_npt_enabled(svm), false);
if (WARN_ON_ONCE(ret))
goto out_free;
svm->nested.force_msr_bitmap_recalc = true;
kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
ret = 0;
out_free:
kfree(save);
kfree(ctl);
return ret;
}
static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
if (WARN_ON(!is_guest_mode(vcpu)))
return true;
if (!vcpu->arch.pdptrs_from_userspace &&
!nested_npt_enabled(svm) && is_pae_paging(vcpu))
/*
* Reload the guest's PDPTRs since after a migration
* the guest CR3 might be restored prior to setting the nested
* state which can lead to a load of wrong PDPTRs.
*/
if (CC(!load_pdptrs(vcpu, vcpu->arch.cr3)))
return false;
if (!nested_svm_vmrun_msrpm(svm)) {
vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
vcpu->run->internal.suberror =
KVM_INTERNAL_ERROR_EMULATION;
vcpu->run->internal.ndata = 0;
return false;
}
if (kvm_hv_verify_vp_assist(vcpu))
return false;
return true;
}
struct kvm_x86_nested_ops svm_nested_ops = {
.leave_nested = svm_leave_nested,
.is_exception_vmexit = nested_svm_is_exception_vmexit,
.check_events = svm_check_nested_events,
.triple_fault = nested_svm_triple_fault,
.get_nested_state_pages = svm_get_nested_state_pages,
.get_state = svm_get_nested_state,
.set_state = svm_set_nested_state,
.hv_inject_synthetic_vmexit_post_tlb_flush = svm_hv_inject_synthetic_vmexit_post_tlb_flush,
};