Bug#688441: 3.2.0 ext3 and ext4 failing in Xen VM domU
Package: linux-image-3.2.0-3-amd64
Version: 3.2.21-3
Severity: serious
Leaves root filesystem in read-only state, some users have reported root
filesystem corruption (see below), so I have marked this as serious
I have a dom0 running Xen (standard squeeze installation) and several
domU VM instances
I've upgraded one of those domU VMs from squeeze to wheezy. Kernel
3.2.0 was installed as part of the upgrade.
Access to all filesystems has been unstable. They often come up in
read-only mode.
I've discovered the same problem discussed here:
http://askubuntu.com/questions/126631/why-do-i-get-disk-i-o-errors-booting-the-3-2-kernel-on-a-xen-vps-server
The discussion ends with a suggestion to add barrier=0 - that seems to
fix the problem for me (so far).
My dom0 system doesn't report any errors with the disk. If I shut down
the domU and fsck the filesystems from the dom0, they all appear
perfectly healthy.
[ 4.787445] EXT3-fs (xvda2): using internal journal
[ 4.940826] loop: module loaded
[ 6.296639] blkfront: barrier: empty write xvda3 op failed
[ 6.296654] blkfront: xvda3: barrier or flush: disabled
[ 6.388461] blkfront: barrier: empty write xvda1 op failed
[ 6.388472] blkfront: xvda1: barrier or flush: disabled
[ 8.843840] kjournald starting. Commit interval 5 seconds
[ 8.881033] EXT3-fs (xvda1): using internal journal
[ 8.881046] EXT3-fs (xvda1): mounted filesystem with ordered data mode
[ 8.916063] kjournald starting. Commit interval 5 seconds
[ 8.948698] EXT3-fs (xvda3): using internal journal
[ 8.948722] EXT3-fs (xvda3): mounted filesystem with ordered data mode
[ 10.152007] blkfront: barrier: empty write xvda2 op failed
[ 10.152023] blkfront: xvda2: barrier or flush: disabled
[ 10.152035] end_request: I/O error, dev xvda2, sector 633144
[ 10.152043] end_request: I/O error, dev xvda2, sector 633144
[ 10.152050] Buffer I/O error on device xvda2, logical block 79143
[ 10.152056] lost page write due to I/O error on xvda2
[ 10.152085] Aborting journal on device xvda2.
[ 10.305595] EXT3-fs (xvda2): error: ext3_journal_start_sb: Detected
aborted journal
[ 10.305617] EXT3-fs (xvda2): error: remounting filesystem read-only
Reply to: