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Date: Sun, 2 Feb 2003 17:20:05 -0800
From: Andrew Morton <akpm@digeo.com>
To: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: linux-kernel@vger.kernel.org
Subject: Re: 2.0, 2.2, 2.4, 2.5: fsync buffer race
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Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> wrote:
>
> > void wait_and_rw_block(...)
> > {
> > 	wait_on_buffer(bh);
> > 	ll_rw_block(...);
> > }
> 
> It would fail if other CPU submits IO with ll_rw_block after
> wait_on_buffer but before ll_rw_block.

In that case, the caller's data gets written anyway, and the caller will wait
upon the I/O which the other CPU started.  So the ll_rw_block() behaviour is
appropriate.
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