linux-kernel - Re: [PATCH] mm: oom: do not reap task if there are live threads in threadgroup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Tue, 24 May 2016 15:21:58 +0300
From:	Vladimir Davydov <vdavydov@...tuozzo.com>
To:	Michal Hocko <mhocko@...nel.org>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>,
	<linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] mm: oom: do not reap task if there are live threads in
 threadgroup

On Tue, May 24, 2016 at 01:46:12PM +0200, Michal Hocko wrote:
> On Tue 24-05-16 14:00:28, Vladimir Davydov wrote:
> > If the current process is exiting, we don't invoke oom killer, instead
> > we give it access to memory reserves and try to reap its mm in case
> > nobody is going to use it. There's a mistake in the code performing this
> > check - we just ignore any process of the same thread group no matter if
> > it is exiting or not - see try_oom_reaper. Fix it.
> 
> This is not a problem with the current code because of 98748bd72200
> ("oom: consider multi-threaded tasks in task_will_free_mem") which got
> merged later on, however.

True, I missed that patch.

> 
> The check is not needed so we can indeed drop it.
> 
> Fixes: 3ef22dfff239 ("oom, oom_reaper: try to reap tasks which skip
> regular OOM killer path")
> 
> Just in case somebody wants to backport only 3ef22dfff239.
> 
> > Signed-off-by: Vladimir Davydov <vdavydov@...tuozzo.com>
> 
> Acked-by: Michal Hocko <mhocko@...e.com>

Thanks.