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Date: Tue, 10 Feb 2009 16:53:33 -0500
From: Paul Clements <paul.clements@steeleye.com>
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To: Andrew Morton <akpm@linux-foundation.org>
CC: linux-kernel@vger.kernel.org, jnelson-kernel-bugzilla@jamponi.net,
       Pavel Machek <pavel@ucw.cz>, stable@kernel.org
Subject: Re: [PATCH 1/1] NBD: fix I/O hang on disconnected nbds
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Andrew Morton wrote:
> On Mon, 09 Feb 2009 13:21:51 -0500
> Paul Clements <paul.clements@steeleye.com> wrote:

>> This problem was introduced by the new request handling thread code
>> ("NBD: allow nbd to be used locally", 3/2008), which entered into 
>> mainline around 2.6.25.
> 
> Seems that the patch applies to 2.6.26, but not to 2.6.25.

OK, couldn't remember the exact timeframe.

>> The fix, which is fairly simple, is to restore the check for lo->sock
>> being NULL in do_nbd_request. This causes I/O to an uninitialized nbd to
>> immediately fail with an I/O error, as it did prior to the introduction 
>> of this bug.
> 
> I marked this as needing backporting into 2.6.26.x, 2.6.27.x and
> 2.6.28.x.  OK?

Yes, that would be a good idea.

Thanks,
Paul