From e90008df1678676fb7e51b4cf38ee0f18c38aeba Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Mon, 5 Mar 2018 12:04:37 -0800 Subject: [PATCH] KVM: VMX: don't configure EPT identity map for unrestricted guest MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit An unrestricted guest can run with hardware CR0.PG==0, i.e. IA32 paging disabled, in which case there is no need to load the guest's CR3 with identity mapped IA32 page tables since hardware will effectively ignore CR3. If unrestricted guest is enabled, don't configure the identity mapped IA32 page table and always load the guest's desired CR3. Signed-off-by: Sean Christopherson Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index a5d2c6977e3c..39216aee60c0 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4490,7 +4490,8 @@ static void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) if (enable_ept) { eptp = construct_eptp(vcpu, cr3); vmcs_write64(EPT_POINTER, eptp); - if (is_paging(vcpu) || is_guest_mode(vcpu)) + if (enable_unrestricted_guest || is_paging(vcpu) || + is_guest_mode(vcpu)) guest_cr3 = kvm_read_cr3(vcpu); else guest_cr3 = vcpu->kvm->arch.ept_identity_map_addr; @@ -9801,7 +9802,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) goto free_vmcs; } - if (enable_ept) { + if (enable_ept && !enable_unrestricted_guest) { err = init_rmode_identity_map(kvm); if (err) goto free_vmcs;