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Date:   Wed, 11 Apr 2018 07:50:02 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Greg Thelen <gthelen@google.com>,
        Wang Long <wanglong19@meituan.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Tejun Heo <tj@kernel.org>, npiggin@gmail.com,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH v3] writeback: safer lock nesting
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On Tue 10-04-18 13:48:37, Andrew Morton wrote:
> On Tue, 10 Apr 2018 08:33:57 +0200 Michal Hocko <mhocko@kernel.org> wrote:
> 
> > > Reported-by: Wang Long <wanglong19@meituan.com>
> > > Signed-off-by: Greg Thelen <gthelen@google.com>
> > > Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613
> > 
> > Not a stable material IMHO
> 
> Why's that?  Wang Long said he's observed the deadlock three times?

I thought it is just too unlikely to hit all the conditions. My fault,
I have completely missed/forgot the fact Wang Long is seeing the issue
happening.

No real objection for the stable backport from me.

-- 
Michal Hocko
SUSE Labs