From 5b61178cd2fd67890a70ae9febbd4df20bbd8c40 Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Thu, 16 Dec 2021 10:19:38 +0800 Subject: [PATCH] KVM: VMX: Mark VCPU_EXREG_CR3 dirty when !CR0_PG -> CR0_PG if EPT + !URG When !CR0_PG -> CR0_PG, vcpu->arch.cr3 becomes active, but GUEST_CR3 is still vmx->ept_identity_map_addr if EPT + !URG. So VCPU_EXREG_CR3 is considered to be dirty and GUEST_CR3 needs to be updated in this case. Reported-by: Maxim Levitsky Suggested-by: Sean Christopherson Signed-off-by: Lai Jiangshan Message-Id: <20211216021938.11752-4-jiangshanlai@gmail.com> Fixes: c62c7bd4f95b ("KVM: VMX: Update vmcs.GUEST_CR3 only when the guest CR3 is dirty") Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/vmx.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index ebf511f83903..1d53b8144f83 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -3071,6 +3071,13 @@ void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) /* Note, vmx_set_cr4() consumes the new vcpu->arch.cr0. */ if ((old_cr0_pg ^ cr0) & X86_CR0_PG) vmx_set_cr4(vcpu, kvm_read_cr4(vcpu)); + + /* + * When !CR0_PG -> CR0_PG, vcpu->arch.cr3 becomes active, but + * GUEST_CR3 is still vmx->ept_identity_map_addr if EPT + !URG. + */ + if (!(old_cr0_pg & X86_CR0_PG) && (cr0 & X86_CR0_PG)) + kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3); } /* depends on vcpu->arch.cr0 to be set to a new value */ -- GitLab