From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755334Ab2LOCi5 (ORCPT ); Fri, 14 Dec 2012 21:38:57 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:53670 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752282Ab2LOCi4 (ORCPT ); Fri, 14 Dec 2012 21:38:56 -0500 Message-ID: <50CBE296.2040107@canonical.com> Date: Fri, 14 Dec 2012 21:38:14 -0500 From: Joseph Salisbury User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121017 Thunderbird/16.0.1 MIME-Version: 1.0 To: Mike Snitzer CC: martin.petersen@oracle.com, Kernel Team , linux-kernel@vger.kernel.org, jgarzik@redhat.com, JBottomley@Parallels.com, Milan Broz Subject: Re: [v3.7 Regression] [SCSI] sd: Implement support for WRITE SAME References: <50CB8C74.3090102@canonical.com> <20121214211159.GA4204@redhat.com> In-Reply-To: <20121214211159.GA4204@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/14/2012 04:11 PM, Mike Snitzer wrote: > On Fri, Dec 14 2012 at 3:30pm -0500, > Joseph Salisbury wrote: > >> Hi Martin, >> >> A bug was opened against the Ubuntu kernel[0]. After a kernel >> bisect, it was found that reverting the following commit resolved >> this bug: >> >> commit 5db44863b6ebbb400c5e61d56ebe8f21ef48b1bd >> Author: Martin K. Petersen >> Date: Tue Sep 18 12:19:32 2012 -0400 >> [SCSI] sd: Implement support for WRITE SAME >> >> The regression was introduced as of v3.7-rc7. >> >> The bug can be reproduced with the following commands, which will >> operate on a virtual scsi_debug device, so they won't change any >> data on the test system. However, this will completely crash the >> system: >> >> sudo modprobe scsi_debug >> sudo luksformat -t ext4 /dev/sdb <- Or whatever device gets assigned >> after inserting scsi_debug. >> sudo cryptsetup luksOpen /dev/sdb treasure >> >> Everything works fine up to here, but the following will cause the crash: >> >> sudo mount /dev/mapper/treasure /mnt >> >> The bug can be reproduced on bare metal, in a VM and on i386 or amd64. >> >> I see that you are the author of this patch, so I wanted to run this >> by you. I was thinking of requesting a revert for v3.7, but I >> wanted to get your feedback first. >> >> >> Thanks, >> >> Joe >> >> >> [0] https://bugs.launchpad.net/bugs/1089818 > The WRITE SAME change was introduced long before v3.7-rc7. I think your > bisect is somehow wrong. From Linus' tree: git describe --contains 5db4486 v3.7-rc7~19^2 Reverting commit 5db4486 solves the bug previously mentioned. > > Milan Broz recently pointed out issues he found with luks when using a > late 3.7-rc (rc7 afaik). Linus fixed that issue with this commit (which > landed in the final v3.7): > http://git.kernel.org/linus/684c9aaebbb0ea3a9954 > > That may not be _the_ problem though. But have you tried the final > v3.7? Yes, v3.7 without reverting 5db4486 exhibits the bug. > > Mike I'll research further and provide additional data.