The host CR0 does not really reflect onto the NPT format because hCR0.PG=1 must be set and hCR0.WP is ignored. Carve that in stone by removing the cr0 argument from kvm_init_shadow_npt_mmu, and while at it pass in WP=1 as well. It does not matter for GMET disabled because PFERR_USER_MASK is always set, but a cleared W bit in the nested page tables cannot be overridden in supervisor mode when GMET is enabled, either. In fact, since CR0.WP=0 is the weird "extra accesses allowed" mode, it is actually easier think about it being always set. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.h | 4 ++-- arch/x86/kvm/mmu/mmu.c | 6 +++--- arch/x86/kvm/svm/nested.c | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index 9031f7ef8e4e..29aa3994a8c2 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -96,8 +96,8 @@ void kvm_mmu_set_me_spte_mask(u64 me_value, u64 me_mask); void kvm_mmu_set_ept_masks(bool has_ad_bits, bool has_mbec); void kvm_init_mmu(struct kvm_vcpu *vcpu); -void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0, - unsigned long cr4, u64 efer, gpa_t nested_cr3); +void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr4, + u64 efer, gpa_t nested_cr3); void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, int huge_page_level, bool accessed_dirty, bool mbec, gpa_t new_eptp); diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 07b64df8519d..432f0d3ce632 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5933,12 +5933,12 @@ static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, shadow_mmu_init_context(vcpu, context, cpu_role, root_role); } -void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0, - unsigned long cr4, u64 efer, gpa_t nested_cr3) +void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr4, + u64 efer, gpa_t nested_cr3) { struct kvm_mmu *context = &vcpu->arch.guest_mmu; struct kvm_mmu_role_regs regs = { - .cr0 = cr0, + .cr0 = X86_CR0_PG | X86_CR0_WP, .cr4 = cr4 & ~X86_CR4_PKE, .efer = efer, }; diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index df232153eb24..a1cffd274000 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -93,7 +93,7 @@ static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu) * 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, + kvm_init_shadow_npt_mmu(vcpu, 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; -- 2.52.0