Re: [PATCH] KVM: SVM: Use a separate vmcb for the nested L2 guest

From: Cathy Avery
Date: Fri Oct 09 2020 - 08:31:58 EST


On 10/8/20 6:23 AM, Maxim Levitsky wrote:
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 0a06e62010d8c..7293ba23b3cbc 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -436,6 +436,9 @@ int enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
WARN_ON(svm->vmcb == svm->nested.vmcb02);
svm->nested.vmcb02->control = svm->vmcb01->control;
+
+ nested_svm_vmloadsave(svm->vmcb01, svm->nested.vmcb02);
+
svm->vmcb = svm->nested.vmcb02;
svm->vmcb_pa = svm->nested.vmcb02_pa;
load_nested_vmcb_control(svm, &nested_vmcb->control);
@@ -622,6 +625,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm)
if (svm->vmcb01->control.asid == 0)
svm->vmcb01->control.asid = svm->nested.vmcb02->control.asid;
+ nested_svm_vmloadsave(svm->nested.vmcb02, svm->vmcb01);
svm->vmcb = svm->vmcb01;
svm->vmcb_pa = svm->nested.vmcb01_pa;
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index b66239b26885d..ee9f87fe611f2 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1097,6 +1097,7 @@ static void init_vmcb(struct vcpu_svm *svm)
clr_cr_intercept(svm, INTERCEPT_CR3_READ);
clr_cr_intercept(svm, INTERCEPT_CR3_WRITE);
save->g_pat = svm->vcpu.arch.pat;
+ svm->nested.vmcb02->save.g_pat = svm->vcpu.arch.pat;
save->cr3 = 0;
save->cr4 = 0;
}

OK this worked for me. Thanks!