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Subject: Re: [RFC][PATCH] splice: fix deadlock
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Jens Axboe <jens.axboe@oracle.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>, Jens Axboe <axboe@suse.de>,
       Eric Dumazet <dada1@cosmosbay.com>, Al Viro <viro@zeniv.linux.org.uk>,
       linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>
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Hi Jens,

On Sun, Jan 18 2009, Vegard Nossum wrote:
>> From 8e1d58b03b47d937bc5e53d902bac6e690709034 Mon Sep 17 00:00:00 2001
>> From: Vegard Nossum <vegard.nossum@gmail.com>
>> Date: Sun, 18 Jan 2009 16:07:29 +0100
>> Subject: [PATCH] splice: fix deadlock
>>
>> splice from a file or socket needs to lock both the file/socket and the
>> pipe inodes. pipe_wait() unlocks only the pipe lock, regardless of the
>> order in which they were taken.
>>
>> This patch adds an additional (optional) argument to pipe_wait(); if
>> specified, pipe_wait() will unlock and reacquire both inode locks.
>>
>> It fixes the lockup that occurs with the test-case below, but please
>> review carefully. Consider this patch a proposal rather than a fix.

On Sun, Jan 18, 2009 at 9:20 PM, Jens Axboe <jens.axboe@oracle.com> wrote:
> Thanks for the bug report and test case, it is indeed buggy! Good
> spotting. I'll review your patch thoroughly and test it, and then
> integrate your patch.

What's the status of this patch? I don't think it ever got merged to mainline.

                          Pekka