From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751967AbcBLRDO (ORCPT ); Fri, 12 Feb 2016 12:03:14 -0500 Received: from imap.thunk.org ([74.207.234.97]:55028 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751050AbcBLRDL (ORCPT ); Fri, 12 Feb 2016 12:03:11 -0500 Date: Fri, 12 Feb 2016 12:03:08 -0500 From: "Theodore Ts'o" To: Georg Altmann Cc: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ext4: clarify error messages for mounting fs w/o journal /w journal options Message-ID: <20160212170308.GC7928@thunk.org> Mail-Followup-To: Theodore Ts'o , Georg Altmann , adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org References: <1455283909-23354-1-git-send-email-george@george-net.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1455283909-23354-1-git-send-email-george@george-net.de> User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 12, 2016 at 02:31:49PM +0100, Georg Altmann wrote: > Previous message was hard to understand: When mounting a ext4 fs without a > journal, but a mount option that controls journaling is used, clearly state > that the fs cannot be mounted with this option because it has no journal. Well, technically it's possible for the file system to have a journal, but for journalling not to be enabled. For example: root@kvm-xfstests:~# dmesg -n 7 root@kvm-xfstests:~# mke2fs -t ext4 -Fq /dev/vdc /dev/vdc contains a ext4 file system created on Fri Feb 12 11:59:10 2016 root@kvm-xfstests:~# dumpe2fs /dev/vdc | grep features dumpe2fs 1.43-WIP (18-May-2015) Filesystem features: has_journal ext_attr resize_inode dir_index filetype extent 64bit flex_bg sparse_super large_file huge_file dir_nlink extra_isize metadata_csum Journal features: (none) root@kvm-xfstests:~# mount -o noload,commit=1 /dev/vdc /vdc 2> /dev/null [ 313.867505] EXT4-fs (vdc): can't mount with commit=1, fs mounted w/o journal So saying "fs has no journal" isn't necessarily going to be correct. Maybe "Can't mount with data=xxx, journalling not enabled" would be less confusing to users? Cheers, - Ted