From: fdbugs Subject: bug when we do an mkfs.ext4 + tune2fs Date: Tue, 20 Jan 2009 13:21:45 +0000 Message-ID: <580e35610901200521x20a9bc85l66ea520151008bc9@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: linux-ext4@vger.kernel.org Return-path: Received: from rv-out-0506.google.com ([209.85.198.227]:29009 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752006AbZATNVq (ORCPT ); Tue, 20 Jan 2009 08:21:46 -0500 Received: by rv-out-0506.google.com with SMTP id k40so3113349rvb.1 for ; Tue, 20 Jan 2009 05:21:45 -0800 (PST) Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi, I have an error when I try to mount an ext4 after having changed its uuid with tune2fs. If I just do an mkfs.ext4 I can mount it, but if I do an mkfs.ext4 and then an e2label -U on it, it can't be mounted. Fortunately this bug is quite easy to reproduce. 1) mkfs.ext4 /dev/xxxx -b 4096 -I 256 -O has_journal,ext_attr,resize_inode,dir_index,filetype,extent,flex_bg,sparse_super,large_file,huge_file,uninit_bg,dir_nlink,extra_isize,^journal_dev 2) "mount -t ext4 /dev/xxxx /mnt/test" works 3) umount /dev/xxxx 4) tune2fs /dev/xxxx -U 19ad8325-2e39-4be1-a6b1-a5d2d1015eeb 5) "mount -t ext4 /dev/xxxx /mnt/test" fails 6) we can see the following error in the log messages EXT4-fs: ext4_check_descriptors: Checksum for group 0 failed (10987!=27579) EXT4-fs: group descriptors corrupted! I am running a 64bit 2.6.27.12 kernel with 64bit binaries, and e2fsprogs-1.41.3. Another user using Ubuntu jaunty alpha3 on a 32bit system has exactly the same problem, so it sounds that all recent ext4 versions are impacted. The mkfs command is quite long just because the list of filesystem features have been saved by a tool which must recreate the filesystem with the same attributes. Thanks