KVM: SVM: Defer nmi processing until switch to host state is complete

If we stgi() too soon, nmis can reach the processor even though interrupts
are disabled, catching it in a half-switched state.  Delay the stgi() until
we're done switching.

Signed-off-by: Avi Kivity <avi@qumranet.com>

drivers/kvm/svm.c

@@ -1585,10 +1585,6 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 #endif
 		: "cc", "memory" );
 
-	local_irq_disable();
-
-	stgi();
-
 	if ((svm->vmcb->save.dr7 & 0xff))
 		load_db_regs(svm->host_db_regs);
 
@@ -1605,6 +1601,10 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
 	reload_tss(vcpu);
 
+	local_irq_disable();
+
+	stgi();
+
 	svm->next_rip = 0;
 }