From: Dave Chinner Subject: Re: ext4 error when testing virtio-scsi & vhost-scsi Date: Mon, 18 Jul 2016 11:53:41 +1000 Message-ID: <20160718015341.GB1922@dastard> References: <20160712164324.GC11020@thunk.org> <20160712230356.GJ1922@dastard> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Theodore Ts'o , kvm@vger.kernel.org, qemu-devel@nongnu.org, target-devel@vger.kernel.org, linux-ext4@vger.kernel.org To: Zhangfei Gao Return-path: Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Fri, Jul 15, 2016 at 03:55:20PM +0800, Zhangfei Gao wrote: > Dear Dave > > On Wed, Jul 13, 2016 at 7:03 AM, Dave Chinner wrote: > > On Tue, Jul 12, 2016 at 12:43:24PM -0400, Theodore Ts'o wrote: > >> On Tue, Jul 12, 2016 at 03:14:38PM +0800, Zhangfei Gao wrote: > >> > Some update: > >> > > >> > If test with ext2, no problem in iblock. > >> > If test with ext4, ext4_mb_generate_buddy reported error in the > >> > removing files after reboot. > >> > > >> > > >> > root@(none)$ rm test > >> > [ 21.006549] EXT4-fs error (device sda): ext4_mb_generate_buddy:758: group 18 > >> > , block bitmap and bg descriptor inconsistent: 26464 vs 25600 free clusters > >> > [ 21.008249] JBD2: Spotted dirty metadata buffer (dev = sda, blocknr = 0). Th > >> > ere's a risk of filesystem corruption in case of system crash. > >> > > >> > Any special notes of using ext4 in qemu? > >> > >> Ext4 has more runtime consistency checking than ext2. So just because > >> ext4 complains doesn't mean that there isn't a problem with the file > >> system; it just means that ext4 is more likely to notice before you > >> lose user data. > >> > >> So if you test with ext2, try running e2fsck afterwards, to make sure > >> the file system is consistent. > >> > >> Given that I'm reguarly testing ext4 using kvm, and I haven't seen > >> anything like this in a very long time, I suspect the problemb is with > >> your SCSI code, and not with ext4. > > > > It's the same error I reported yesterday for ext3 on 4.7-rc6 when > > rebooting a VM after it hung. > > > Any link of this error? http://article.gmane.org/gmane.comp.file-systems.ext4/53792 Cheers, Dave. -- Dave Chinner david@fromorbit.com