KVM: SVM: Sync efer back into nested vmcb
This patch fixes a bug in a nested hypervisor that heavily
switches between real-mode and long-mode. The problem is
fixed by syncing back efer into the guest vmcb on emulated
vmexit.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 8a3f9f6..09704a0 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1896,6 +1896,7 @@
nested_vmcb->save.ds = vmcb->save.ds;
nested_vmcb->save.gdtr = vmcb->save.gdtr;
nested_vmcb->save.idtr = vmcb->save.idtr;
+ nested_vmcb->save.efer = svm->vcpu.arch.efer;
nested_vmcb->save.cr0 = kvm_read_cr0(&svm->vcpu);
nested_vmcb->save.cr3 = svm->vcpu.arch.cr3;
nested_vmcb->save.cr2 = vmcb->save.cr2;