From: Michal Hocko <mhocko@kernel.org>
To: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: ytk.lee@samsung.com, "linux-mm@kvack.org" <linux-mm@kvack.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Oleg Nesterov <oleg@redhat.com>,
David Rientjes <rientjes@google.com>,
Vladimir Davydov <vdavydov.dev@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] mm, oom_adj: avoid meaningless loop to find processes sharing mm
Date: Tue, 9 Oct 2018 13:10:05 +0200 [thread overview]
Message-ID: <20181009111005.GK8528@dhcp22.suse.cz> (raw)
In-Reply-To: <df4b029c-16b4-755f-2672-d7ec116f78ba@i-love.sakura.ne.jp>
On Tue 09-10-18 19:00:44, Tetsuo Handa wrote:
> On 2018/10/09 16:50, Michal Hocko wrote:
[...]
> > Well, that is unfortunate indeed and it
> > breaks the OOM_SCORE_ADJ_MIN contract. There are basically two ways here
> > 1) do not care and encourage users to use a saner way to set
> > OOM_SCORE_ADJ_MIN because doing that externally is racy anyway e.g.
> > setting it before [v]fork & exec. Btw. do we know about an actual user
> > who would care?
>
> I'm not talking about [v]fork & exec. Why are you talking about [v]fork & exec ?
Because that is the only raceless way to set your oom_score_adj.
> > 2) add OOM_SCORE_ADJ_MIN and do not kill tasks sharing mm and do not
> > reap the mm in the rare case of the race.
>
> That is no problem. The mistake we made in 4.6 was that we updated oom_score_adj
> to -1000 (and allowed unprivileged users to OOM-lockup the system).
I do not follow.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2018-10-09 11:10 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20181008011931epcms1p82dd01b7e5c067ea99946418bc97de46a@epcms1p8>
2018-10-08 1:19 ` Yong-Taek Lee
2018-10-08 2:52 ` Tetsuo Handa
[not found] ` <CGME20181008011931epcms1p82dd01b7e5c067ea99946418bc97de46a@epcms1p5>
2018-10-08 6:14 ` Yong-Taek Lee
2018-10-08 6:22 ` Tetsuo Handa
[not found] ` <CGME20181008011931epcms1p82dd01b7e5c067ea99946418bc97de46a@epcms1p2>
2018-10-08 8:38 ` Yong-Taek Lee
2018-10-08 9:27 ` Tetsuo Handa
2018-10-09 6:35 ` Michal Hocko
2018-10-09 7:50 ` Michal Hocko
2018-10-09 10:00 ` Tetsuo Handa
2018-10-09 11:10 ` Michal Hocko [this message]
2018-10-09 12:52 ` Tetsuo Handa
2018-10-09 12:58 ` Michal Hocko
2018-10-09 13:14 ` Tetsuo Handa
2018-10-09 13:26 ` Michal Hocko
2018-10-09 13:51 ` Tetsuo Handa
2018-10-09 14:09 ` Michal Hocko
2018-10-09 8:02 ` Michal Hocko
[not found] <CGME20181005063208epcms1p22959cd2f771ad017996e2b18266791ea@epcms1p2>
2018-10-05 6:32 ` Yong-Taek Lee
2018-10-09 6:23 ` Michal Hocko
2018-10-09 8:03 ` Michal Hocko
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