From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Chinner <david@fromorbit.com>
Subject: Re: Wrong DIF guard tag on ext2 write
Date: Sat, 24 Jul 2010 11:03:59 +1000
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Cc: Gennadiy Nerubayev <parakie@gmail.com>,
	James Bottomley <James.Bottomley@suse.de>,
	Christof Schmitt <christof.schmitt@de.ibm.com>,
	Boaz Harrosh <bharrosh@panasas.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, Chris Mason <chris.mason@oracle.com>
To: Vladislav Bolkhovitin <vst@vlnb.net>
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On Fri, Jul 23, 2010 at 11:16:33PM +0400, Vladislav Bolkhovitin wrote:
> It would be great if you prove or disprove our suspicions that Linux
> can produce several write requests for the same blocks
> simultaneously. To be sure we need:

Just use direct IO. Case in point is the concurrent sub-block
AIO-DIO data corruption we're chasing on XFS and ext4 at the moment
where we have two concurrent unaligned write IOs to the same
filesystem block:

http://oss.sgi.com/archives/xfs/2010-07/msg00278.html

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com