From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] cgroup,freezer: hold cpu_hotplug_lock before
 freezer_mutex in freezer_css_{online,offline}()
Date: Mon, 12 Jun 2023 06:43:30 -1000
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Sender: Tejun Heo <htejun-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
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To: Tetsuo Handa <penguin-kernel-1yMVhJb1mP/7nzcFbJAaVXf5DAMn2ifp@public.gmane.org>
Cc: Zefan Li <lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>

On Sun, Jun 11, 2023 at 10:48:12PM +0900, Tetsuo Handa wrote:
> syzbot is again reporting circular locking dependency between
> cpu_hotplug_lock and freezer_mutex. Do like what we did with
> commit 57dcd64c7e036299 ("cgroup,freezer: hold cpu_hotplug_lock
> before freezer_mutex").
> 
> Reported-by: syzbot <syzbot+2ab700fe1829880a2ec6-Pl5Pbv+GP7P466ipTTIvnc23WoclnBCfAL8bYrjMMd8@public.gmane.org>
> Closes: https://syzkaller.appspot.com/bug?extid=2ab700fe1829880a2ec6
> Signed-off-by: Tetsuo Handa <penguin-kernel-JPay3/Yim36HaxMnTkn67Xf5DAMn2ifp@public.gmane.org>
> Tested-by: syzbot <syzbot+2ab700fe1829880a2ec6-Pl5Pbv+GP7P466ipTTIvnc23WoclnBCfAL8bYrjMMd8@public.gmane.org>

Tagged w/ the same stable version as the earlier patch and applied to
cgroup/for-6.4-fixes.

Thanks.

-- 
tejun