KVM: VMX: Qualify check for host NMI

Check for the exit reason first; this allows us, later,
to avoid a VMREAD for VM_EXIT_INTR_INFO_FIELD.

Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 53bf6ae..89130ba 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3905,7 +3905,8 @@
 		kvm_machine_check();
 
 	/* We need to handle NMIs before interrupts are enabled */
-	if ((exit_intr_info & INTR_INFO_INTR_TYPE_MASK) == INTR_TYPE_NMI_INTR &&
+	if (vmx->exit_reason == EXIT_REASON_EXCEPTION_NMI &&
+	    (exit_intr_info & INTR_INFO_INTR_TYPE_MASK) == INTR_TYPE_NMI_INTR &&
 	    (exit_intr_info & INTR_INFO_VALID_MASK)) {
 		kvm_before_handle_nmi(&vmx->vcpu);
 		asm("int $2");