3.13.11.6 -stable review patch.  If anyone has any objections, please let me 
know.

------------------

From: David Vrabel <[email protected]>

commit 1b6478231c6f5f844185acb32045cf195028cfce upstream.

Calling xen_console_resume() in xen_suspend() causes a warning because
it locks irq_mapping_update_lock (a mutex) and this may sleep.  If a
userspace process is using the evtchn device then this mutex may be
locked at the point of the stop_machine() call and
xen_console_resume() would then deadlock.

Resuming the console after stop_machine() returns avoids this
deadlock.

Signed-off-by: David Vrabel <[email protected]>
Reviewed-by: Boris Ostrovsky <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
---
 drivers/xen/manage.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index 624e8dc..0bc8086 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -95,7 +95,6 @@ static int xen_suspend(void *data)
 
        if (!si->cancelled) {
                xen_irq_resume();
-               xen_console_resume();
                xen_timer_resume();
        }
 
@@ -152,6 +151,10 @@ static void do_suspend(void)
 
        err = stop_machine(xen_suspend, &si, cpumask_of(0));
 
+       /* Resume console as early as possible. */
+       if (!si.cancelled)
+               xen_console_resume();
+
        dpm_resume_start(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
 
        if (err) {
-- 
1.9.1

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