Re: Crashes with 874bbfe600a6 in 3.18.25

From: Jan Kara
Date: Thu Jan 21 2016 - 04:52:34 EST


On Wed 20-01-16 13:39:01, Shaohua Li wrote:
> On Wed, Jan 20, 2016 at 10:19:26PM +0100, Jan Kara wrote:
> > Hello,
> >
> > a friend of mine started seeing crashes with 3.18.25 kernel - once
> > appropriate load is put on the machine it crashes within minutes. He
> > tracked down that reverting commit 874bbfe600a6 (this is the commit ID from
> > Linus' tree, in stable tree the commit ID is 1e7af294dd03) "workqueue: make
> > sure delayed work run in local cpu" makes the kernel stable again. I'm
> > attaching screenshot of the crash - sadly the initial part is missing but
> > it seems that we crashed when processing timers on otherwise idle CPU. This
> > is a production machine so experimentation is not easy but if we really
> > need more information it may be possible to reproduce the issue again and
> > gather it.
> >
> > Anyone has idea what is going on? I was looking into the code for a while
> > but so far I have no good explanation. It would be good to understand the
> > cause instead of just blindly reverting the commit from stable tree...
>
> Tejun fixed a bug in timer: 22b886dd10180939. is it included in 3.18.25?

That doesn't seem to be included in 3.18-stable although it was CCed to stable.
Sasha?

Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR