KVM: fix ack not being delivered when msi present

kvm_notify_acked_irq does not check irq type, so that it sometimes
interprets msi vector as irq.  As a result, ack notifiers are not
called, which typially hangs the guest.  The fix is to track and
check irq type.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

include/linux/kvm_host.h

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 16713dc..3060bdc3 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -110,6 +110,7 @@
 
 struct kvm_kernel_irq_routing_entry {
 	u32 gsi;
+	u32 type;
 	int (*set)(struct kvm_kernel_irq_routing_entry *e,
 		    struct kvm *kvm, int level);
 	union {

virt/kvm/irq_comm.c

diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index a8bd466..ddc17f0 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -160,7 +160,8 @@
 	unsigned gsi = pin;
 
 	list_for_each_entry(e, &kvm->irq_routing, link)
-		if (e->irqchip.irqchip == irqchip &&
+		if (e->type == KVM_IRQ_ROUTING_IRQCHIP &&
+		    e->irqchip.irqchip == irqchip &&
 		    e->irqchip.pin == pin) {
 			gsi = e->gsi;
 			break;
@@ -259,6 +260,7 @@
 	int delta;
 
 	e->gsi = ue->gsi;
+	e->type = ue->type;
 	switch (ue->type) {
 	case KVM_IRQ_ROUTING_IRQCHIP:
 		delta = 0;