From: Eric Sandeen Subject: Re: How to run xfstests against multipath disks on SuSE? Date: Tue, 27 Nov 2012 14:37:09 -0600 Message-ID: <50B52475.1020603@redhat.com> References: <20121126145559.GK31891@thunk.org> <20121127031438.GK6434@dastard> <50B4F38E.8060806@redhat.com> <20121127203537.GM6434@dastard> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ryan Wang , "Theodore Ts'o" , =?UTF-8?B?THVrw6HFoSBDemVybmVy?= , linux-ext4@vger.kernel.org, xfs@oss.sgi.com To: Dave Chinner Return-path: Received: from mx1.redhat.com ([209.132.183.28]:47620 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756559Ab2K0UhT (ORCPT ); Tue, 27 Nov 2012 15:37:19 -0500 In-Reply-To: <20121127203537.GM6434@dastard> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 11/27/12 2:35 PM, Dave Chinner wrote: > On Tue, Nov 27, 2012 at 11:08:30AM -0600, Eric Sandeen wrote: >> On 11/26/12 9:14 PM, Dave Chinner wrote: >>> On Tue, Nov 27, 2012 at 09:20:47AM +0800, Ryan Wang wrote: >>>> 2012/11/26 Theodore Ts'o : >>>>> On Mon, Nov 26, 2012 at 02:43:40PM +0100, Luk=C3=A1=C5=A1 Czerner= wrote: >>>>>>> The I checked the script common.rc, and found that it uses >>>>>>> df to determine the filesystem type and it uses the realpath >>>>>>> "/dev/dm-0" instead of "/dev/mapper/mpatha", while df always >>>>>>> shows "devtmpfs" instead of "ext4" for /dev/dm-0. >>>>>>> >>>>>>> I run "mount" and found that devtmpfs is mount on /dev/ on open= suse >>>>>>> ***by default***. Even though I run "mount -t btrfs /dev/dm-0 = /somedir", >>>>>>> df still showed devtmpfs. >>>>>>> >>>>>>> Any ideas to kick off the xfstests? >>>>> >>>>> At least with the df which ships with Debian Testing, df will dis= play >>>>> the file system in use if it matches the device name which is >>>>> /etc/mtab. It looks the issue is that mount is canonicalizing th= e >>>>> device name to be the human friendly version: >>>>> >>>>> # ls -l /dev/mapper/closure-bigscratch >>>>> 0 lrwxrwxrwx 1 root root 7 Nov 16 15:15 /dev/mapper/closure-bigsc= ratch -> ../dm-7 >>>>> {/home/tytso/bin}, level 2 >>>>> # mount /dev/dm-7 /u2 >>>>> # df /u2 >>>>> Filesystem 1K-blocks Used Available Use% Mo= unted on >>>>> /dev/mapper/closure-bigscratch 52403200 224772 52178428 1% /u= 2 >>>>> # grep /u2 /etc/mtab >>>>> /dev/mapper/closure-bigscratch /u2 xfs rw,relatime,attr2,inode64,= noquota 0 0 >>>>> >>>>> So the simplest solution is to just use /dev/mapper/mpatha instea= d of >>>>> insisting on using /dev/dm-0. That's what I do.... >>>> >>>> In xfstests/common.rc, it will use realpath to obtain /dev/dm-0, e= ven if you >>>> specified /dev/mapper/mpatha. >>>> My problem is in SuSE, the devtmpfs is mounted on /dev by default,= seems >>>> used by udev. And df reports devtmpfs on /dev/dm-0, instead of ext= 4. >>> >>> What version of xfstests are you using? Do you have a >>> "README.device-mapper" file in the base directory? If not, upgrade >>> to the latest version and retry. >>> >>> $ gl -n 1 -p 0a81886 >>> commit 0a818862bb74932e15971ec8bedb55765ec3a3f6 >>> Author: Christoph Hellwig >>> Date: Wed May 4 16:28:32 2011 +0200 >>> >>> xfstests: support post-udev device mapper nodes >>> >>> Because of udevs complaining device mapper now creates /dev/dm-= N as the real >>> device nodes, and just symlinks the /dev/mapper/ names to it. = This would be >>> easy if everything used the /dev/mapper clear names, but most s= ystem utilities >>> translate them back to the /dev/mapper/ names and thus confuse = various test >>> cases. Add support to _is_block_dev to read symlinks, and add = documentation >>> on how to run xfstests on device mapper volumes. >>> >>> Signed-off-by: Christoph Hellwig >>> Reviewed-by: Alex Elder >>> >>> Cheers, >>> >>> Dave. >>> >> >> Recent "realpath" changes also went in: >> >> b03c662399956609934ff063e9064e15dc7459ac xfstests: fix to build src/= realpath and the correct the existence of target devices >> d5ea873fcbf00b841f0511a26fb341364a5c6425 xfstests: resolve symlinked= devices to real paths >> >> so either of those could have broken and/or fixed it for you :) >=20 > Yup, those are almost certainly the patches that broke device mapper > support. There' aren't changes to common.rc, so I didn't notice them. > They basically override the fix that Christoph made to support > /dev/mapper links properly. >=20 > I'd suggest a revert is in order, the two patches above were part > of Rich's hovering of old, unreviewed patches. This problem was > already fixed in a different way by Christoph, so adding these > patches was wrong. =46ine with me ... Ryan, can you test w/o those, and if it works - Rich, can you revert those please? -Eric > Cheers, >=20 > Dave. >=20 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html