[ 3.8.y.z extended stable ] Patch "PM / Sleep: avoid 'autosleep' in shutdown progress" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    PM / Sleep: avoid 'autosleep' in shutdown progress

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.6.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From d8eedc2176b5629ce59600ad7cfcf1a0b34adbc7 Mon Sep 17 00:00:00 2001
From: Liu ShuoX <shuox.liu at intel.com>
Date: Thu, 11 Jul 2013 16:03:45 +0800
Subject: PM / Sleep: avoid 'autosleep' in shutdown progress

commit e5248a111bf4048a9f3fab1a9c94c4630a10592a upstream.

Prevent automatic system suspend from happening during system
shutdown by making try_to_suspend() check system_state and return
immediately if it is not SYSTEM_RUNNING.

This prevents the following breakage from happening (scenario from
Zhang Yanmin):

 Kernel starts shutdown and calls all device driver's shutdown
 callback.  When a driver's shutdown is called, the last wakelock is
 released and suspend-to-ram starts.  However, as some driver's shut
 down callbacks already shut down devices and disabled runtime pm,
 the suspend-to-ram calls driver's suspend callback without noticing
 that device is already off and causes crash.

[rjw: Changelog]
Signed-off-by: Liu ShuoX <shuox.liu at intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 kernel/power/autosleep.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c
index ca304046..ab79ecb 100644
--- a/kernel/power/autosleep.c
+++ b/kernel/power/autosleep.c
@@ -32,7 +32,8 @@ static void try_to_suspend(struct work_struct *work)

 	mutex_lock(&autosleep_lock);

-	if (!pm_save_wakeup_count(initial_count)) {
+	if (!pm_save_wakeup_count(initial_count) ||
+		system_state != SYSTEM_RUNNING) {
 		mutex_unlock(&autosleep_lock);
 		goto out;
 	}
--
1.8.1.2