On Wed, Feb 17, 2021, Maxim Levitsky wrote:
On Wed, 2021-02-17 at 17:06 +0100, Paolo Bonzini wrote:
On 17/02/21 15:57, Maxim Levitsky wrote:
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b3e36dc3f164..e428d69e21c0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6921,13 +6921,15 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
if (unlikely((u16)vmx->exit_reason.basic == EXIT_REASON_MCE_DURING_VMENTRY))
kvm_machine_check();
+ if (likely(!vmx->exit_reason.failed_vmentry))
+ vmx->idt_vectoring_info = vmcs_read32(IDT_VECTORING_INFO_FIELD);
+
Any reason for the if?
Sean Christopherson asked me to do this to avoid updating idt_vectoring_info on failed
VM entry, to keep things as they were logically before this patch.
Ya, specifically because the field isn't valid if VM-Enter fails. I'm also ok
with an unconditional VMREAD if we add a comment stating that it's unnecessary
if VM-Enter failed, but faster in the common case.