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Date: Wed, 20 Jan 2016 13:39:01 -0800
From: Shaohua Li <shli@fb.com>
To: Jan Kara <jack@suse.cz>
CC: LKML <linux-kernel@vger.kernel.org>, <stable@vger.kernel.org>,
        Tejun Heo <tj@kernel.org>, Daniel Bilik <daniel.bilik@neosystem.cz>,
        Sasha Levin <sasha.levin@oracle.com>
Subject: Re: Crashes with 874bbfe600a6 in 3.18.25
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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?

Thanks,
Shaohua