Patch "cpuset: use trialcs->mems_allowed as a temp variable" has been added to the 4.1-stable tree

This is a note to let you know that I've just added the patch titled

    cpuset: use trialcs->mems_allowed as a temp variable

to the 4.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
cpuset-use-trialcs-mems_allowed-as-a-temp-variable.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Alban Crequy <[email protected]>
Date: Thu, 6 Aug 2015 16:21:05 +0200
Subject: cpuset: use trialcs->mems_allowed as a temp variable
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From: Alban Crequy <[email protected]>

commit 24ee3cf89bef04e8bc23788aca4e029a3f0f06d9 upstream.

The comment says it's using trialcs->mems_allowed as a temp variable but it didn't match the code. Change the code to match the comment.

This fixes an issue when writing in cpuset.mems when a sub-directory
exists: we need to write several times for the information to persist:

| root@alban:/sys/fs/cgroup/cpuset# mkdir footest9
| root@alban:/sys/fs/cgroup/cpuset# cd footest9
| root@alban:/sys/fs/cgroup/cpuset/footest9# mkdir aa
| root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems
|
| root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > cpuset.mems
| root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems
|
| root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > cpuset.mems
| root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems
| 0
| root@alban:/sys/fs/cgroup/cpuset/footest9# cat aa/cpuset.mems
|
| root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > aa/cpuset.mems
| root@alban:/sys/fs/cgroup/cpuset/footest9# cat aa/cpuset.mems
| 0
| root@alban:/sys/fs/cgroup/cpuset/footest9#

This should help to fix the following issue in Docker:
https://github.com/opencontainers/runc/issues/133
In some conditions, a Docker container needs to be started twice in order to work.

---
 kernel/cpuset.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -1223,7 +1223,7 @@ static int update_nodemask(struct cpuset
 	spin_unlock_irq(&callback_lock);
 
 	/* use trialcs->mems_allowed as a temp variable */
-	update_nodemasks_hier(cs, &cs->mems_allowed);
+	update_nodemasks_hier(cs, &trialcs->mems_allowed);
 done:
 	return retval;
 }

Patches currently in stable-queue which might be from [email protected] are

queue-4.1/cpuset-use-trialcs-mems_allowed-as-a-temp-variable.patch