Merge branch 'linus' into patchwork

* linus: (1465 commits)
  ARM: tegra30: clocks: Fix pciex clock registration
  lseek(fd, n, SEEK_END) does *not* go to eof - n
  Linux 3.10-rc6
  smp.h: Use local_irq_{save,restore}() in !SMP version of on_each_cpu().
  powerpc: Fix missing/delayed calls to irq_work
  powerpc: Fix emulation of illegal instructions on PowerNV platform
  powerpc: Fix stack overflow crash in resume_kernel when ftracing
  snd_pcm_link(): fix a leak...
  use can_lookup() instead of direct checks of ->i_op->lookup
  move exit_task_namespaces() outside of exit_notify()
  fput: task_work_add() can fail if the caller has passed exit_task_work()
  xfs: don't shutdown log recovery on validation errors
  xfs: ensure btree root split sets blkno correctly
  xfs: fix implicit padding in directory and attr CRC formats
  xfs: don't emit v5 superblock warnings on write
  mei: me: clear interrupts on the resume path
  mei: nfc: fix nfc device freeing
  mei: init: Flush scheduled work before resetting the device
  sctp: fully initialize sctp_outq in sctp_outq_init
  netiucv: Hold rtnl between name allocation and device registration.
  ...

1 files changed, 36 insertions, 1 deletions

diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index 3159a37d966d..a7e25073de19 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -29,6 +29,8 @@
 #include "xenbus_probe.h"
 
 
+static struct workqueue_struct *xenbus_frontend_wq;
+
 /* device/<type>/<id> => <type>-<id> */
 static int frontend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
 {
@@ -89,9 +91,40 @@ static void backend_changed(struct xenbus_watch *watch,
 	xenbus_otherend_changed(watch, vec, len, 1);
 }
 
+static void xenbus_frontend_delayed_resume(struct work_struct *w)
+{
+	struct xenbus_device *xdev = container_of(w, struct xenbus_device, work);
+
+	xenbus_dev_resume(&xdev->dev);
+}
+
+static int xenbus_frontend_dev_resume(struct device *dev)
+{
+	/*
+	 * If xenstored is running in this domain, we cannot access the backend
+	 * state at the moment, so we need to defer xenbus_dev_resume
+	 */
+	if (xen_store_domain_type == XS_LOCAL) {
+		struct xenbus_device *xdev = to_xenbus_device(dev);
+
+		if (!xenbus_frontend_wq) {
+			pr_err("%s: no workqueue to process delayed resume\n",
+			       xdev->nodename);
+			return -EFAULT;
+		}
+
+		INIT_WORK(&xdev->work, xenbus_frontend_delayed_resume);
+		queue_work(xenbus_frontend_wq, &xdev->work);
+
+		return 0;
+	}
+
+	return xenbus_dev_resume(dev);
+}
+
 static const struct dev_pm_ops xenbus_pm_ops = {
 	.suspend	= xenbus_dev_suspend,
-	.resume		= xenbus_dev_resume,
+	.resume		= xenbus_frontend_dev_resume,
 	.freeze		= xenbus_dev_suspend,
 	.thaw		= xenbus_dev_cancel,
 	.restore	= xenbus_dev_resume,
@@ -440,6 +473,8 @@ static int __init xenbus_probe_frontend_init(void)
 
 	register_xenstore_notifier(&xenstore_notifier);
 
+	xenbus_frontend_wq = create_workqueue("xenbus_frontend");
+
 	return 0;
 }
 subsys_initcall(xenbus_probe_frontend_init);