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Date: Thu, 19 Apr 2018 12:14:04 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
Subject: Re: [patch v2] mm, oom: fix concurrent munlock and oom reaper
 unmap
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To: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: mhocko@kernel.org, akpm@linux-foundation.org, aarcange@redhat.com, guro@fb.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org

On Thu, 19 Apr 2018, Tetsuo Handa wrote:

> current code has a possibility that the OOM reaper is disturbed by
> unpredictable dependencies, like I worried that
> 
>   I think that there is a possibility that the OOM reaper tries to reclaim
>   mlocked pages as soon as exit_mmap() cleared VM_LOCKED flag by calling
>   munlock_vma_pages_all().
> 
> when current approach was proposed.

That's exactly the issue that this patch is fixing, yes.  If you brought 
that possibility up then I'm sorry that it was ignored.