KVM: x86: make translate_nested_gpa vendor-specific

EPT and NPT have different rules for passing PFERR_USER_MASK to the
nested page table walk.  In particular, for final addresses EPT
uses the U bit of the guest (nGVA->nGPA) walk.

While at it, remove PFERR_USER_MASK from the VMX version of the
function, since it is actually ignored by the tables that
update_permission_bitmask() generates for EPT.

Tested-by: David Riley <d.riley@proxmox.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2026-04-08 11:42:02 -04:00
parent 2c89d57754
commit b95b398d2e
6 changed files with 36 additions and 23 deletions

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@ -2010,6 +2010,10 @@ struct kvm_x86_nested_ops {
struct kvm_nested_state *kvm_state);
bool (*get_nested_state_pages)(struct kvm_vcpu *vcpu);
int (*write_log_dirty)(struct kvm_vcpu *vcpu, gpa_t l2_gpa);
gpa_t (*translate_nested_gpa)(struct kvm_vcpu *vcpu, gpa_t gpa,
u64 access,
struct x86_exception *exception,
u64 pte_access);
int (*enable_evmcs)(struct kvm_vcpu *vcpu,
uint16_t *vmcs_version);

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@ -2041,7 +2041,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
* read with kvm_read_guest().
*/
if (!hc->fast && is_guest_mode(vcpu)) {
hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa,
hc->ingpa = kvm_x86_ops.nested_ops->translate_nested_gpa(
vcpu, hc->ingpa,
PFERR_GUEST_FINAL_MASK, NULL, 0);
if (unlikely(hc->ingpa == INVALID_GPA))
return HV_STATUS_INVALID_HYPERCALL_INPUT;

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@ -294,10 +294,6 @@ static inline void kvm_update_page_stats(struct kvm *kvm, int level, int count)
atomic64_add(count, &kvm->stat.pages[level - 1]);
}
gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
struct x86_exception *exception,
u64 pte_access);
static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu,
struct kvm_mmu *mmu,
gpa_t gpa, u64 access,
@ -306,8 +302,9 @@ static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu,
{
if (mmu != &vcpu->arch.nested_mmu)
return gpa;
return translate_nested_gpa(vcpu, gpa, access, exception,
pte_access);
return kvm_x86_ops.nested_ops->translate_nested_gpa(vcpu, gpa, access,
exception,
pte_access);
}
static inline bool kvm_has_mirrored_tdp(const struct kvm *kvm)

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@ -2071,8 +2071,23 @@ static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
return true;
}
static gpa_t svm_translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa,
u64 access,
struct x86_exception *exception,
u64 pte_access)
{
struct kvm_mmu *mmu = vcpu->arch.mmu;
BUG_ON(!mmu_is_nested(vcpu));
/* NPT walks are always user-walks */
access |= PFERR_USER_MASK;
return mmu->gva_to_gpa(vcpu, mmu, gpa, access, exception);
}
struct kvm_x86_nested_ops svm_nested_ops = {
.leave_nested = svm_leave_nested,
.translate_nested_gpa = svm_translate_nested_gpa,
.is_exception_vmexit = nested_svm_is_exception_vmexit,
.check_events = svm_check_nested_events,
.triple_fault = nested_svm_triple_fault,

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@ -7438,8 +7438,20 @@ __init int nested_vmx_hardware_setup(int (*exit_handlers[])(struct kvm_vcpu *))
return 0;
}
static gpa_t vmx_translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa,
u64 access,
struct x86_exception *exception,
u64 pte_access)
{
struct kvm_mmu *mmu = vcpu->arch.mmu;
BUG_ON(!mmu_is_nested(vcpu));
return mmu->gva_to_gpa(vcpu, mmu, gpa, access, exception);
}
struct kvm_x86_nested_ops vmx_nested_ops = {
.leave_nested = vmx_leave_nested,
.translate_nested_gpa = vmx_translate_nested_gpa,
.is_exception_vmexit = nested_vmx_is_exception_vmexit,
.check_events = vmx_check_nested_events,
.has_events = vmx_has_nested_events,

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@ -7848,22 +7848,6 @@ void kvm_get_segment(struct kvm_vcpu *vcpu,
kvm_x86_call(get_segment)(vcpu, var, seg);
}
gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
struct x86_exception *exception,
u64 pte_access)
{
struct kvm_mmu *mmu = vcpu->arch.mmu;
gpa_t t_gpa;
BUG_ON(!mmu_is_nested(vcpu));
/* NPT walks are always user-walks */
access |= PFERR_USER_MASK;
t_gpa = mmu->gva_to_gpa(vcpu, mmu, gpa, access, exception);
return t_gpa;
}
gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva,
struct x86_exception *exception)
{