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Date: Tue, 11 Sep 2018 18:37:09 +0200
From: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH] mm, oom: Introduce time limit for dump_tasks duration.
Message-ID: <20180911163708.GB27989@redhat.com>
References: <0252ad5d-46e6-0d7f-ef91-4e316657a83d@i-love.sakura.ne.jp>
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To: Michal Hocko <mhocko@kernel.org>
Cc: Dmitry Vyukov <dvyukov@google.com>, Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>, Andrew Morton <akpm@linux-foundation.org>, David Rientjes <rientjes@google.com>, syzbot <syzbot+f0fc7f62e88b1de99af3@syzkaller.appspotmail.com>, 'Dmitry Vyukov' via syzkaller-upstream-moderation <syzkaller-upstream-moderation@googlegroups.com>, linux-mm <linux-mm@kvack.org>

On 09/06, Michal Hocko wrote:
>
> Ccing Oleg.

Thanks, but somehow I can't find this patch on marc.info ...

> So a question for Oleg I guess. Is it possible that for_each_process
> live locks (or stalls for way too long/unbounded amount of time) under
> heavy fork/exit loads?

Oh yes, it can... plus other problems.

I even sent the initial patches which introduce for_each_process_break/continue
a long ago... I'll try to find them tommorrow and resend.

Oleg.