Merge tag 'for-linus-6.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - two small cleanup patches

 - a fix for PCI passthrough under Xen

 - a four patch series speeding up virtio under Xen with user space
   backends

* tag 'for-linus-6.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen-pciback: Consider INTx disabled when MSI/MSI-X is enabled
  xen: privcmd: Add support for ioeventfd
  xen: evtchn: Allow shared registration of IRQ handers
  xen: irqfd: Use _IOW instead of the internal _IOC() macro
  xen: Make struct privcmd_irqfd's layout architecture independent
  xen/xenbus: Add __counted_by for struct read_buffer and use struct_size()
  xenbus: fix error exit in xenbus_init()

Author: torvalds

drivers/xen/Kconfig

@@ -269,12 +269,12 @@ config XEN_PRIVCMD
 	  disaggregated Xen setups this driver might be needed for other
 	  domains, too.
 
-config XEN_PRIVCMD_IRQFD
-	bool "Xen irqfd support"
+config XEN_PRIVCMD_EVENTFD
+	bool "Xen Ioeventfd and irqfd support"
 	depends on XEN_PRIVCMD && XEN_VIRTIO && EVENTFD
 	help
-	  Using the irqfd mechanism a virtio backend running in a daemon can
-	  speed up interrupt injection into a guest.
+	  Using the ioeventfd / irqfd mechanism a virtio backend running in a
+	  daemon can speed up interrupt delivery from / to a guest.
 
 config XEN_ACPI_PROCESSOR
 	tristate "Xen ACPI processor"

drivers/xen/events/events_base.c

@@ -1229,7 +1229,8 @@ static int bind_evtchn_to_irq_chip(evtchn_port_t evtchn, struct irq_chip *chip,
 		bind_evtchn_to_cpu(evtchn, 0, false);
 	} else {
 		struct irq_info *info = info_for_irq(irq);
-		WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
+		if (!WARN_ON(!info || info->type != IRQT_EVTCHN))
+			info->refcnt++;
 	}
 
 out:

drivers/xen/evtchn.c

@@ -397,7 +397,7 @@ static int evtchn_bind_to_user(struct per_user_data *u, evtchn_port_t port,
 	if (rc < 0)
 		goto err;
 
-	rc = bind_evtchn_to_irqhandler_lateeoi(port, evtchn_interrupt, 0,
+	rc = bind_evtchn_to_irqhandler_lateeoi(port, evtchn_interrupt, IRQF_SHARED,
 					       u->name, evtchn);
 	if (rc < 0)
 		goto err;