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Date: Mon, 23 Apr 2018 10:09:20 -0600
From: Michal Hocko <mhocko@kernel.org>
Subject: Re: [patch v2] mm, oom: fix concurrent munlock and oom reaper unmap
Message-ID: <20180423160920.GX17484@dhcp22.suse.cz>
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To: David Rientjes <rientjes@google.com>, Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Andrew Morton <akpm@linux-foundation.org>, Andrea Arcangeli <aarcange@redhat.com>, Roman Gushchin <guro@fb.com>, linux-kernel@vger.kernel.org, linux-mm@kvack.org

On Sun 22-04-18 07:18:57, Michal Hocko wrote:
> On Sat 21-04-18 20:45:11, David Rientjes wrote:
[...]
> Maybe invoking the reaper as suggested by Tetsuo will help here. Maybe
> we will come up with something more smart. But I would like to have a
> stop gap solution for stable that is easy enough. And your patch is not
> doing that because it adds a very subtle dependency on the page lock.
> So please stop repeating your arguments all over and either come with
> an argument which proves me wrong and the lock_page dependency is not
> real or come with an alternative solution which doesn't make
> MMF_OOM_SKIP depend on the page lock.

I though I would give this a try but I am at a conference and quite
busy. Tetsuo are you willing to give it a try so that we have something
to compare and decide, please?
-- 
Michal Hocko
SUSE Labs