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Date: Tue, 17 Jan 2012 17:03:23 -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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Hello,

On Wed, Jan 18, 2012 at 09:01:00AM +0800, Shaohua Li wrote:
> 2012/1/18 Vivek Goyal <vgoyal@redhat.com>:
> >> Does the following patch make any difference?
> >
> > Nope. Still can reproduce the issue.
>
> I had similar issue too. Looks ioc_create_icq finds an icq (in ioc_lookup_icq)
> the icq is in rcu free (it has __rcu_icq_cache set)

Vivek is seeing the problem while switching elevators.  Are you too?
Or is it during normal operation?

Thanks.

--
tejun