From: Jan Kara Subject: Re: norecovery option for ext3 Date: Fri, 20 Nov 2009 21:54:59 +0100 Message-ID: <20091120205459.GB15631@duck.suse.cz> References: <20091120122403.GD15422@duck.suse.cz> <4B06B9CA.1030502@redhat.com> <745F9F90-6F43-4DA1-92B7-0AC09E07981C@sun.com> <4B06D83F.8040203@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andreas Dilger , Jan Kara , linux-ext4@vger.kernel.org, tytso@mit.edu To: Eric Sandeen Return-path: Received: from cantor.suse.de ([195.135.220.2]:54535 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755657AbZKTUyy (ORCPT ); Fri, 20 Nov 2009 15:54:54 -0500 Content-Disposition: inline In-Reply-To: <4B06D83F.8040203@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Fri 20-11-09 11:56:15, Eric Sandeen wrote: > Andreas Dilger wrote: > > On 2009-11-20, at 07:46, Eric Sandeen wrote: > >> Jan Kara wrote: > >>> I've tried to test noload/norecovery option of ext3 and I've found > >>> it simply does not work. The filesystem does not even mount. > > > >>> Given that nobody used the option (OK, some googling shows that > >>> somebody tried to use it in *2.4.9* kernel and it didn't work even > >>> there - Stephen Tweedie comments that it's an obsolete option meant > >>> for use during fs development) and seeing how badly corrupted the > >>> filesystem is when you don't replay the journal, I'd just remove the > >>> option. Any opinions? > >> > >> Oh, sigh. Sorry, didn't actually, er, test it, since I was just > >> adding an alias for the option... bleah. > >> > >> I think we should fix it; there are cases when you may want to mount > >> that way, I think - for example, otherwise there is no way at all to > >> mounta block device which is marked readonly... > > > > > > Won't this require implementing "no journal" mode for ext3? Seems like > > a lot of effort, when ext4 does the same thing (i.e. they could just > > mount the filesystem "-t ext4 -o norecovery" if they really, really need > > to do that). > > I don't see why it would need nojournal mode; you'd have to: > > mount -o ro,norecovery > > anyway, and if it's ro the journal should be non-operational anyway right? > > (Jan, did you mount -o norecovery or -o ro,norecovery in your tests?) Actually, just -o norecovery but after the oops I've looked at the code and concluded that -o ro won't help the oops anyway... But yes, fixing the code in read-only mode should be possible. Honza -- Jan Kara SUSE Labs, CR