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Date: Tue, 17 Jan 2012 17:11:12 -0800
From: Tejun Heo <tj@kernel.org>
To: Shaohua Li <shaohua.li@intel.com>
Cc: Vivek Goyal <vgoyal@redhat.com>,
        linux kernel mailing list <linux-kernel@vger.kernel.org>,
        Jens Axboe <axboe@kernel.dk>
Subject: Re: Kernel crash in icq_free_icq_rcu
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On Wed, Jan 18, 2012 at 09:05:26AM +0800, Shaohua Li wrote:
> > Vivek is seeing the problem while switching elevators.  Are you too?
> > Or is it during normal operation?
> same here. I had some problems when I debug my ioscheduler, but
> eventually found even switching cfq and noop can trigger oops.

Hmmm... maybe quiescing isn't working as expected and kmem cache is
being destroyed with live icq's.  I'll try to reproduce it.

Thanks.

-- 
tejun