From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH block/for-linus] cgroup,writeback: don't switch wbs
 immediately on dead wbs if the memcg is dead
Date: Mon, 11 Nov 2019 08:18:16 -0800
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To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Sasha Levin <sashal@kernel.org>, stable@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org, cgroups@vger.kernel.org, kernel-team@fb.com, Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, Jan Kara <jack@suse.cz>, Konstantin Khlebnikov <khlebnikov@yandex-team.ru>, Dennis Zhou <dennis@kernel.org>, Michal Hocko <mhocko@kernel.org>

Hello, Michal.

On Mon, Nov 11, 2019 at 02:15:44PM +0100, Michal Hocko wrote:
> > Signed-off-by: Tejun Heo <tj@kernel.org>
> > Cc: Dennis Zhou <dennis@kernel.org>
> > Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
> > Fixes: e8a7abf5a5bd ("writeback: disassociate inodes from dying bdi_writebacks")
> 
> Is this a stable material?

c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if mapping has
no dirty pages") likely addresses larger part of the problem, but yeah
it prolly makes sense to backport both for -stable.

Greg, Sasha, can you pick the following two commits for -stable?

* c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if mapping has
  no dirty pages")

* 65de03e25138 ("cgroup,writeback: don't switch wbs immediately on
  dead wbs if the memcg is dead")

Both are fixes for e8a7abf5a5bd ("writeback: disassociate inodes from
dying bdi_writebacks") - v4.2+.

Thanks.

-- 
tejun