From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] cgroup: avoid attaching a cgroup root to two different
 superblocks
Date: Tue, 11 Apr 2017 09:01:23 +0900
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To: Zefan Li <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
Cc: dvyukov-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>

On Fri, Apr 07, 2017 at 04:51:55PM +0800, Zefan Li wrote:
> We end up using the same cgroup root for two different superblocks,
> so percpu_ref_kill() will be called twice on the same root when the
> two superblocks are destroyed.
> 
> We should fix to make sure the superblock pinning is really successful.
> 
> Cc: stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org # 3.16+
> Reported-by: Dmitry Vyukov <dvyukov-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> Signed-off-by: Zefan Li <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>

Applied to cgroup/for-4.11-fixes.

Thanks.

-- 
tejun