From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: Wrong DIF guard tag on ext2 write Date: Mon, 31 May 2010 10:20:44 -0400 Message-ID: References: <20100531112817.GA16260@schmichrtp.mainz.de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org To: Christof Schmitt Return-path: In-Reply-To: <20100531112817.GA16260@schmichrtp.mainz.de.ibm.com> (Christof Schmitt's message of "Mon, 31 May 2010 13:28:18 +0200") Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org >>>>> "Christof" == Christof Schmitt writes: Christof> Since the guard tags are created in Linux, it seems that the Christof> data attached to the write request changes between the Christof> generation in bio_integrity_generate and the call to Christof> sd_prep_fn. Yep, known bug. Page writeback locking is messed up for buffer_head users. The extNfs folks volunteered to look into this a while back but I don't think they have found the time yet. Christof> Using ext3 or ext4 instead of ext2 does not show the problem. Last I looked there were still code paths in ext3 and ext4 that permitted pages to be changed during flight. I guess you've just been lucky. -- Martin K. Petersen Oracle Linux Engineering