From: Oleg Nesterov <oleg@redhat.com>
To: David Rientjes <rientjes@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Kyle Walker <kwalker@redhat.com>,
Michal Hocko <mhocko@kernel.org>,
Stanislav Kozina <skozina@redhat.com>,
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH -mm 3/3] mm/oom_kill: fix the wrong task->mm == mm checks in
Date: Wed, 30 Sep 2015 15:50:51 +0200 [thread overview]
Message-ID: <20150930135051.GD32263@redhat.com> (raw)
In-Reply-To: <alpine.DEB.2.10.1509291541010.3375@chino.kir.corp.google.com>
On 09/29, David Rientjes wrote:
>
> On Tue, 29 Sep 2015, Oleg Nesterov wrote:
>
> > Both "child->mm == mm" and "p->mm != mm" checks in oom_kill_process()
> > are wrong. ->mm can be if task is the exited group leader. This means
> > in particular that "kill sharing same memory" loop can miss a process
> > with a zombie leader which uses the same ->mm.
> >
> > Note: the process_has_mm(child, p->mm) check is still not 100% correct,
> > p->mm can be NULL too. This is minor, but probably deserves a fix or a
> > comment anyway.
> >
> > Signed-off-by: Oleg Nesterov <oleg@redhat.com>
>
> Acked-by: David Rientjes <rientjes@google.com>
>
> I like this and I don't want to hold up a fix for a personal preference,
> but I find process_has_mm() to simply imply the process has a non-NULL mm.
Hmm, yes ;)
> Maybe process_shares_mm()? Something to consider.
Agreed, will rename in v2.
Oleg.
next prev parent reply other threads:[~2015-09-30 13:54 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-29 14:17 [PATCH -mm 0/3] mm/oom_kill: ensure we actually kill all tasks sharing the same mm Oleg Nesterov
2015-09-29 14:18 ` [PATCH -mm 1/3] mm/oom_kill: remove the wrong fatal_signal_pending() Oleg Nesterov
2015-09-29 22:36 ` David Rientjes
2015-09-30 1:42 ` Tetsuo Handa
2015-09-30 13:47 ` Oleg Nesterov
2015-09-30 15:20 ` [PATCH -mm 1/3] mm/oom_kill: remove the wrongfatal_signal_pending() Tetsuo Handa
2015-09-30 13:43 ` [PATCH -mm 1/3] mm/oom_kill: remove the wrong fatal_signal_pending() Oleg Nesterov
2015-09-29 14:18 ` [PATCH -mm 2/3] mm/oom_kill: cleanup the "kill sharing same memory" Oleg Nesterov
2015-09-29 22:39 ` David Rientjes
2015-09-30 13:49 ` Oleg Nesterov
2015-09-29 14:18 ` [PATCH -mm 3/3] mm/oom_kill: fix the wrong task->mm == mm checks in Oleg Nesterov
2015-09-29 22:41 ` David Rientjes
2015-09-30 13:50 ` Oleg Nesterov [this message]
2015-09-30 2:16 ` Tetsuo Handa
2015-09-30 13:59 ` Oleg Nesterov
2015-09-30 18:23 ` [PATCH -mm v2 0/3] mm/oom_kill: ensure we actually kill all tasks sharing the same mm Oleg Nesterov
2015-09-30 18:24 ` [PATCH -mm v2 1/3] mm/oom_kill: remove the wrong fatal_signal_pending() check in oom_kill_process() Oleg Nesterov
2015-09-30 21:14 ` David Rientjes
2015-10-01 10:52 ` [PATCH -mm v2 1/3] mm/oom_kill: remove the wrong fatal_signal_pending()check " Tetsuo Handa
2015-10-01 12:49 ` [PATCH -mm v2 1/3] mm/oom_kill: remove the wrong fatal_signal_pending() check " Michal Hocko
2015-10-01 15:00 ` Oleg Nesterov
2015-10-01 15:27 ` Michal Hocko
2015-10-01 15:41 ` Oleg Nesterov
2015-10-01 16:19 ` Michal Hocko
2015-10-01 17:53 ` Oleg Nesterov
2015-10-02 11:32 ` Tetsuo Handa
2015-10-02 12:11 ` Michal Hocko
2015-10-02 12:33 ` Tetsuo Handa
2015-10-02 13:32 ` Michal Hocko
2015-10-02 13:57 ` Oleg Nesterov
2015-10-02 14:24 ` Michal Hocko
2015-10-02 14:07 ` Tetsuo Handa
2015-10-02 14:15 ` Oleg Nesterov
2015-10-02 13:52 ` Oleg Nesterov
2015-10-02 14:36 ` Tetsuo Handa
2015-09-30 18:24 ` [PATCH -mm v2 2/3] mm/oom_kill: cleanup the "kill sharing same memory" loop Oleg Nesterov
2015-09-30 21:15 ` David Rientjes
2015-10-01 12:50 ` Michal Hocko
2015-09-30 18:24 ` [PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm checks in oom_kill_process() Oleg Nesterov
2015-09-30 21:15 ` David Rientjes
2015-10-01 12:56 ` Michal Hocko
2015-10-01 22:24 ` Andrew Morton
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20150930135051.GD32263@redhat.com \
--to=oleg@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=kwalker@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mhocko@kernel.org \
--cc=penguin-kernel@i-love.sakura.ne.jp \
--cc=rientjes@google.com \
--cc=skozina@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).