From d555f7057ebe34aae42fe2f592a3047e9b151326 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 22 Jun 2021 10:57:04 -0700 Subject: [PATCH] KVM: x86/mmu: Grab shadow root level from mmu_role for shadow MMUs Use the mmu_role to initialize shadow root level instead of assuming the level of KVM's shadow root (host) is the same as that of the guest root, or in the case of 32-bit non-PAE paging where KVM forces PAE paging. For nested NPT, the shadow root level cannot be adapted to L1's NPT root level and is instead always the TDP root level because NPT uses the current host CR0/CR4/EFER, e.g. 64-bit KVM can't drop into 32-bit PAE to shadow L1's NPT. Signed-off-by: Sean Christopherson Message-Id: <20210622175739.3610207-20-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/mmu.c | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 0c23a6d5722d..466cb93eb3b5 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3898,7 +3898,6 @@ static void nonpaging_init_context(struct kvm_vcpu *vcpu, context->sync_page = nonpaging_sync_page; context->invlpg = NULL; context->root_level = 0; - context->shadow_root_level = PT32E_ROOT_LEVEL; context->direct_map = true; context->nx = false; } @@ -4466,10 +4465,10 @@ static void update_last_nonleaf_level(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu static void paging64_init_context_common(struct kvm_vcpu *vcpu, struct kvm_mmu *context, - int level) + int root_level) { context->nx = is_nx(vcpu); - context->root_level = level; + context->root_level = root_level; reset_rsvds_bits_mask(vcpu, context); update_permission_bitmask(vcpu, context, false); @@ -4481,7 +4480,6 @@ static void paging64_init_context_common(struct kvm_vcpu *vcpu, context->gva_to_gpa = paging64_gva_to_gpa; context->sync_page = paging64_sync_page; context->invlpg = paging64_invlpg; - context->shadow_root_level = level; context->direct_map = false; } @@ -4509,7 +4507,6 @@ static void paging32_init_context(struct kvm_vcpu *vcpu, context->gva_to_gpa = paging32_gva_to_gpa; context->sync_page = paging32_sync_page; context->invlpg = paging32_invlpg; - context->shadow_root_level = PT32E_ROOT_LEVEL; context->direct_map = false; } @@ -4669,6 +4666,8 @@ static void shadow_mmu_init_context(struct kvm_vcpu *vcpu, struct kvm_mmu *conte else paging32_init_context(vcpu, context); + context->shadow_root_level = new_role.base.level; + context->mmu_role.as_u64 = new_role.as_u64; reset_shadow_zero_bits_mask(vcpu, context); } @@ -4704,16 +4703,9 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0, __kvm_mmu_new_pgd(vcpu, nested_cr3, new_role.base); - if (new_role.as_u64 != context->mmu_role.as_u64) { + if (new_role.as_u64 != context->mmu_role.as_u64) shadow_mmu_init_context(vcpu, context, cr0, cr4, efer, new_role); - /* - * Override the level set by the common init helper, nested TDP - * always uses the host's TDP configuration. - */ - context->shadow_root_level = new_role.base.level; - } - /* * Redo the shadow bits, the reset done by shadow_mmu_init_context() * (above) may use the wrong shadow_root_level.