Re: WARNING in try_charge

From: Michal Hocko
Date: Mon Aug 06 2018 - 10:58:37 EST


On Mon 06-08-18 23:41:22, Tetsuo Handa wrote:
> +David Howells
>
> On 2018/08/06 20:32, Michal Hocko wrote:
> > On Mon 06-08-18 04:27:02, syzbot wrote:
> >> Hello,
> >>
> >> syzbot has tested the proposed patch and the reproducer did not trigger
> >> crash:
> >>
> >> Reported-and-tested-by:
> >> syzbot+bab151e82a4e973fa325@xxxxxxxxxxxxxxxxxxxxxxxxx
> >>
> >> Tested on:
> >>
> >> commit: 8c8399e0a3fb Add linux-next specific files for 20180806
> >> git tree: linux-next
> >> kernel config: https://syzkaller.appspot.com/x/.config?x=1b6bc1781e49e93e
> >> compiler: gcc (GCC) 8.0.1 20180413 (experimental)
> >> patch: https://syzkaller.appspot.com/x/patch.diff?x=14fe18e2400000
> >>
> >> Note: testing is done by a robot and is best-effort only.
> >
> > OK, so this smells like a problem in the previous group oom changes. Or
> > maybe it is not very easy to reproduce?
> >
>
> Since I can't find mm related changes between next-20180803 (syzbot can reproduce) and
> next-20180806 (syzbot has not reproduced), I can't guess what makes this problem go away.

Hmm, but original report was against 4.18.0-rc6-next-20180725+ kernel.
And that one had the old group oom code. /me confused.
--
Michal Hocko
SUSE Labs