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From: Jens Axboe <axboe@kernel.dk>
To: Shaohua Li <shaohua.li@intel.com>
Cc: lkml <linux-kernel@vger.kernel.org>
Subject: Re: [patch 1/2]block, cfq: fix empty queue crash caused by request merge
Date: Fri, 16 Dec 2011 13:56:33 +0100	[thread overview]
Message-ID: <4EEB4001.8010205@kernel.dk> (raw)
In-Reply-To: <1324000362.22361.452.camel@sli10-conroe>

On 2011-12-16 02:52, Shaohua Li wrote:
> All requests of a queue could be merged to other requests of other queue.
> Such queue will not have request in it, but it's in service tree. This
> will cause kernel oops.
> I encounter a BUG_ON() in cfq_dispatch_request() with next patch, but the
> issue should exist without the patch.

Good catch, yes I think this could happen if you just happen to have a
very deliberate/unlucky set of processes and timings. Applied.


-- 
Jens Axboe


      reply	other threads:[~2011-12-16 12:56 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-12-16  1:52 [patch 1/2]block, cfq: fix empty queue crash caused by request merge Shaohua Li
2011-12-16 12:56 ` Jens Axboe [this message]

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