From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Parnell Subject: Re: Bug In ext4 in kernels > 2.6.39 - Not mounting with arguments/options I specify in fstab on root remount Date: Mon, 07 Nov 2011 17:48:15 -0800 Message-ID: <4EB88A5F.1050507@gmail.com> References: <4E6F6D89.5040905@redhat.com> <20111009234433.GU7948@thunk.org> <4EA0E72D.8020305@gmail.com> <20111022050031.GC4196@thunk.org> <4EA27607.20407@gmail.com> <20111022093218.GF4196@thunk.org> <4EB7416A.7080006@gmail.com> <4EB76C21.5060104@gmail.com> <20111107154759.GB24234@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Eric Sandeen , linux-ext4@vger.kernel.org To: Ted Ts'o Return-path: Received: from mail-iy0-f174.google.com ([209.85.210.174]:53915 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752062Ab1KGXtK (ORCPT ); Mon, 7 Nov 2011 18:49:10 -0500 Received: by iage36 with SMTP id e36so6394837iag.19 for ; Mon, 07 Nov 2011 15:49:09 -0800 (PST) In-Reply-To: <20111107154759.GB24234@thunk.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 11/07/2011 07:47 AM, Ted Ts'o wrote: > On Sun, Nov 06, 2011 at 09:26:57PM -0800, Matt Parnell wrote: >> I figured it out. data=writeback isn't needed and is done by default >> if there's no journal, as per commit >> 373cd5c53d5ea6622c319ecd84e29e2737d488bd http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=373cd5c53d5ea6622c319ecd84e29e2737d488bd >> >> ...sorry about throwing you guys through loops over this, although >> I'm guessing there's still a bug in that the kernel should just warn >> the user about the option when it's used and otherwise ignore it >> instead of breaking if there's no journal. > Ah, OK. It wasn't clear to me that you were running without a year. > You're right, we shouldn't complain in that case, since we ignore the > messages when mounting the file system. Actually, we parse the > options when we are mounting the file system, but then we zero them > out when we discover that there's no journal; but in any case, we > should similarly ignore the pointless data=* mount options (for a file > system w/o a journal) on the remount operation as well. > > - Ted > > commit eb513689c97e3e73bb9b4459d490a8e894b4a546 > Author: Theodore Ts'o > Date: Mon Nov 7 10:47:42 2011 -0500 > > ext4: ignore journalled data options on remount if fs has no journal > > This avoids a confusing failure in the init scripts when the > /etc/fstab has data=writeback or data=journal but the file system does > not have a journal. So check for this case explicitly, and warn the > user that we are ignoring the (pointless, since they have no journal) > data=* mount option. > > Signed-off-by: "Theodore Ts'o" > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 9953d80..0435013 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -1683,7 +1683,9 @@ static int parse_options(char *options, struct super_block *sb, > data_opt = EXT4_MOUNT_WRITEBACK_DATA; > datacheck: > if (is_remount) { > - if (test_opt(sb, DATA_FLAGS) != data_opt) { > + if (!sbi->s_journal) > + ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option"); > + else if (test_opt(sb, DATA_FLAGS) != data_opt) { > ext4_msg(sb, KERN_ERR, > "Cannot change data mode on remount"); > return 0; Great! I'm glad we managed to track this one down. I'm not using the flags anymore, but I'll be glad when your patch there makes it into ext4 for other users.