xen/irq: The Xen hypervisor cleans up the PIRQs if the other domain forgot.

And if the other domain forgot to clean up its PIRQs we don't need
to fail the operation. Just take a note of it and continue on.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

drivers/xen/events.c

@@ -728,7 +728,14 @@ int xen_destroy_irq(int irq)
 		unmap_irq.pirq = info->u.pirq.pirq;
 		unmap_irq.domid = info->u.pirq.domid;
 		rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
-		if (rc) {
+		/* If another domain quits without making the pci_disable_msix
+		 * call, the Xen hypervisor takes care of freeing the PIRQs
+		 * (free_domain_pirqs).
+		 */
+		if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF))
+			printk(KERN_INFO "domain %d does not have %d anymore\n",
+				info->u.pirq.domid, info->u.pirq.pirq);
+		else if (rc) {
 			printk(KERN_WARNING "unmap irq failed %d\n", rc);
 			goto out;
 		}