From: Theodore Tso Subject: Re: [PATCH 1/2] ext4: journal all modifications in ext4_xattr_set_handle Date: Fri, 6 Nov 2009 21:33:41 -0500 Message-ID: <20091107023341.GF26342@mit.edu> References: <4AF4A334.1000304@redhat.com> <4AF4A49F.8030005@redhat.com> <55C0D494-12AD-4EF7-8C35-411B2B5151EF@sun.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Eric Sandeen , ext4 development To: Andreas Dilger Return-path: Received: from thunk.org ([69.25.196.29]:33772 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753542AbZKGCdj (ORCPT ); Fri, 6 Nov 2009 21:33:39 -0500 Content-Disposition: inline In-Reply-To: <55C0D494-12AD-4EF7-8C35-411B2B5151EF@sun.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Fri, Nov 06, 2009 at 05:22:51PM -0700, Andreas Dilger wrote: > On 2009-11-06, at 15:35, Eric Sandeen wrote: >> Eric Sandeen wrote: >>> ext4_xattr_set_handle() was modifying s_inode_size outside >>> of journaling constraints; this is one of the accesses that >>> was causing the crc errors in journal replay as seen in >>> kernel.org bugzilla #14354. >> >> Oh, and for those who haven't been following the bug, big >> thanks to Chris Mason for helping to look into this and coming >> up with the debugging patch that made it obvious... > > It would be great, IMHO, to have this debugging patch submitted to > the kernel also, and enabled under a CONFIG option. The debugging patch is only safe when the file system's block size == page size. I suppose we could leave a warning in Kconfig that the debugging option is only safe to be used when all of the file systems in the system have a 4k (or whatever the page size happens to be) block size, but it's probably better to clean up the patch so that it's only enabled on a mount option, and then only if the file system block size is the same as the page size. > I'd also be interested to see the "write shadow buffer to journal" > one-line patch that was discussed in the bug. Which patch are you referring to? - Ted