From: Michal Hocko <mhocko@kernel.org>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Dmitry Vyukov <dvyukov@google.com>,
syzbot <syzbot+bab151e82a4e973fa325@syzkaller.appspotmail.com>,
cgroups@vger.kernel.org, Johannes Weiner <hannes@cmpxchg.org>,
LKML <linux-kernel@vger.kernel.org>,
Linux-MM <linux-mm@kvack.org>,
syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
Vladimir Davydov <vdavydov.dev@gmail.com>
Subject: Re: WARNING in try_charge
Date: Mon, 6 Aug 2018 13:09:34 +0200 [thread overview]
Message-ID: <20180806110934.GJ19540@dhcp22.suse.cz> (raw)
In-Reply-To: <884de816-671a-44d4-a6a1-2ad7eff53715@I-love.SAKURA.ne.jp>
On Mon 06-08-18 19:47:00, Tetsuo Handa wrote:
> On 2018/08/06 19:39, Dmitry Vyukov wrote:
> > On Mon, Aug 6, 2018 at 11:48 AM, Michal Hocko <mhocko@kernel.org> wrote:
> >> Btw. running with the above diff on top might help us to ideantify
> >> whether this is a pre-mature warning or a valid one. Still useful to
> >> find out.
>
> Since syzbot already found a syz reproducer, you can ask syzbot to test it.
>
> >
> > The bug report has a reproducer, so you can run it with the patch. Or
> > ask syzbot to test your patch:
> > https://github.com/google/syzkaller/blob/master/docs/syzbot.md#testing-patches
> > Which basically boils down to saying:
> >
> > #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > master
>
> Excuse me, but this is linux-next only problem. Therefore,
If this really is a linux-next only problem then please retest with the
current linux-next which has dropped the and replaced the group oom
code.
> #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 4603ad75c9a9..852cd3dbdcd9 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -1388,6 +1388,8 @@ static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
> bool ret;
>
> mutex_lock(&oom_lock);
> + pr_info("task=%s pid=%d invoked memcg oom killer. oom_victim=%d\n",
> + current->comm, current->pid, tsk_is_oom_victim(current));
> ret = out_of_memory(&oc);
> mutex_unlock(&oom_lock);
> return ret;
>
> F.Y.I. Waiting until __mmput() completes (with timeout using OOM score feedback)
> ( https://syzkaller.appspot.com/x/patch.diff?x=101e449c400000 ) solves this race.
Which just means that something else is broken. Seriously, timout is not
going to fix anything. It merely changes the picture.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2018-08-06 11:09 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-04 13:33 WARNING in try_charge syzbot
2018-08-04 13:45 ` Tetsuo Handa
2018-08-05 11:33 ` Tetsuo Handa
2018-08-05 8:14 ` syzbot
2018-08-06 9:15 ` Michal Hocko
2018-08-06 9:30 ` Dmitry Vyukov
2018-08-06 9:48 ` Michal Hocko
2018-08-06 10:34 ` Dmitry Vyukov
2018-08-06 11:02 ` Michal Hocko
2018-08-06 11:57 ` Dmitry Vyukov
2018-08-06 14:21 ` Michal Hocko
2018-08-06 14:58 ` Dmitry Vyukov
2018-08-06 17:30 ` Michal Hocko
2018-08-06 17:53 ` Dmitry Vyukov
2018-08-06 15:07 ` Dmitry Vyukov
2018-08-06 15:31 ` Johannes Weiner
2018-08-06 10:39 ` Dmitry Vyukov
2018-08-06 10:47 ` Tetsuo Handa
2018-08-06 11:09 ` Michal Hocko [this message]
2018-08-06 11:27 ` syzbot
2018-08-06 11:32 ` Michal Hocko
2018-08-06 11:58 ` Dmitry Vyukov
2018-08-06 14:41 ` Tetsuo Handa
2018-08-06 14:58 ` Michal Hocko
2018-08-06 15:12 ` Tetsuo Handa
2018-08-06 14:54 ` David Howells
2018-08-06 15:04 ` Tetsuo Handa
2018-08-06 11:00 ` syzbot
2018-08-06 15:32 ` Tetsuo Handa
2018-08-06 15:42 ` syzbot
2018-08-06 16:02 ` Tetsuo Handa
2018-08-06 17:44 ` Michal Hocko
2018-08-06 17:49 ` Dmitry Vyukov
2018-08-06 17:56 ` Michal Hocko
2018-08-06 18:13 ` Michal Hocko
2018-08-06 18:23 ` syzbot
2018-08-06 18:55 ` Michal Hocko
2018-08-06 19:12 ` syzbot
2018-08-06 19:45 ` Michal Hocko
2018-08-06 19:46 ` Michal Hocko
2018-08-07 11:18 ` Dmitry Vyukov
2018-08-07 11:25 ` Michal Hocko
2018-08-06 18:39 ` Michal Hocko
2018-08-06 20:26 ` Tetsuo Handa
2018-08-06 20:34 ` Michal Hocko
2018-08-06 20:46 ` Tetsuo Handa
2018-08-06 20:55 ` Michal Hocko
2018-08-06 21:50 ` Tetsuo Handa
2018-08-07 10:19 ` Tetsuo Handa
2018-08-09 13:57 ` Tetsuo Handa
2018-08-09 15:07 ` Michal Hocko
2018-08-09 21:05 ` Tetsuo Handa
2018-08-09 15:34 ` Johannes Weiner
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=20180806110934.GJ19540@dhcp22.suse.cz \
--to=mhocko@kernel.org \
--cc=cgroups@vger.kernel.org \
--cc=dvyukov@google.com \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=penguin-kernel@I-love.SAKURA.ne.jp \
--cc=syzbot+bab151e82a4e973fa325@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=vdavydov.dev@gmail.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).