On Thu, Jan 05, 2012 at 05:14:28PM +0100, Sander Eikelenboom wrote: > > OK spoke too soon, i have been able to trigger it again: > - copying files from LV to the same LV without the snapshot went OK > - copying from the RO snapshot of a LV to the same LV gave the error while copying the file again: OK. Originally, you said you did this: 1) fsck -v -p -f the filesystem 2) mount the filesystem 3) Try to copy a file 4) filesystem will be mounted RO on error (see below) 5) fsck again, journal will be recovered, no other errors 6) start at 1) Was this with with a read-only snapshot always being in existence through all of these five steps? When was the RO snapshot created? If a RO snapshot has to be there in order for this to happen, then this is almost certainly a device-mapper regression. (dm-devel folks, this is a problem which apparently occurred when the user went from v3.1.5 to v3.2, so this looks likes 3.2 regression.) - Ted > > [ 2357.655783] EXT4-fs error (device dm-2): ext4_mb_generate_buddy:739: group 1861, 32254 clusters in bitmap, 32258 in gd > [ 2357.656056] Aborting journal on device dm-2-8. > [ 2357.718473] EXT4-fs (dm-2): Remounting filesystem read-only > [ 2357.736680] EXT4-fs error (device dm-2) in ext4_da_write_end:2532: IO failure > [ 2357.738328] EXT4-fs (dm-2): ext4_da_writepages: jbd2_start: 7615 pages, ino 4079617; err -30 > [ 2716.125010] EXT4-fs error (device dm-2): ext4_put_super:818: Couldn't clean up the journal > > > Attached are 4x output from dumpe2fs > - dumpe2fs-xen_images-3.2.0 Made just after boot > - dumpe2fs-xen_images-3.2.0-afterfsck Made after doing a fsck -v -p -f on the unmounted LV > - dumpe2fs-xen_images-3.2.0-aftererror Made after the error occured on the mounted LV > - dumpe2fs-xen_images-3.2.0-aftererror-afterfsck Made after the error occured, and after a subsequent fsck -v -p -f on the unmounted LV > - dumpe2fs-xen_images-3.1.5 Made after booting into 3.1.5 after all of the above > > Oh yes also did a badblock scan to rule that out, and it seems the numbers stay the same. > e2fsck 1.41.12 (17-May-2010) (from debian squeeze) > > -- > Sander > > > > >> > >> -- > >> Sander > >> > >> > >> This is a forwarded message > >> From: Sander Eikelenboom <linux@xxxxxxxxxxxxxx> > >> To: "Theodore Ts'o" <tytso@xxxxxxx> > >> Date: Thursday, January 5, 2012, 11:37:59 AM > >> Subject: can't recover ext4 on lvm from ext4_mb_generate_buddy:739: group 1687, 32254 clusters in bitmap, 32258 in gd > >> > >> ===8<==============Original message text=============== > >> > >> I'm having some troubles with a ext4 filesystem on LVM, it seems bricked and fsck doesn't seem to find and correct the problem. > >> > >> Steps: > >> 1) fsck -v -p -f the filesystem > >> 2) mount the filesystem > >> 3) Try to copy a file > >> 4) filesystem will be mounted RO on error (see below) > >> 5) fsck again, journal will be recovered, no other errors > >> 6) start at 1) > >> > >> > >> I think the way i bricked it is: > >> - make a lvm snapshot from that lvm logical disk > >> - mount that lvm snapshot as RO > >> - try to copy a file from that mounted RO snapshot to a diffrent dir on the lvm logical disk the snapshot is from. > >> - it fails and i can't recover (see above) > >> > >> > >> Is there a way to recover from this ? > >> > >> > >> > >> [ 220.748928] EXT4-fs error (device dm-2): ext4_mb_generate_buddy:739: group 1687, 32254 clusters in bitmap, 32258 in gd > >> [ 220.749415] Aborting journal on device dm-2-8. > >> [ 220.771633] EXT4-fs error (device dm-2): ext4_journal_start_sb:327: Detected aborted journal > >> [ 220.772593] EXT4-fs (dm-2): Remounting filesystem read-only > >> [ 220.792455] EXT4-fs (dm-2): Remounting filesystem read-only > >> [ 220.805118] EXT4-fs (dm-2): ext4_da_writepages: jbd2_start: 9680 pages, ino 4079617; err -30 > >> serveerstertje:/mnt/xen_images/domains/production# cd / > >> serveerstertje:/# umount /mnt/xen_images/ > >> serveerstertje:/# fsck -f -v -p /dev/serveerstertje/xen_images > >> fsck from util-linux-ng 2.17.2 > >> /dev/mapper/serveerstertje-xen_images: recovering journal > >> > >> 277 inodes used (0.00%) > >> 5 non-contiguous files (1.8%) > >> 0 non-contiguous directories (0.0%) > >> # of inodes with ind/dind/tind blocks: 41/41/3 > >> Extent depth histogram: 69/28/2 > >> 51890920 blocks used (79.18%) > >> 0 bad blocks > >> 41 large files > >> > >> 199 regular files > >> 53 directories > >> 0 character device files > >> 0 block device files > >> 0 fifos > >> 0 links > >> 16 symbolic links (16 fast symbolic links) > >> 0 sockets > >> -------- > >> 268 files > >> serveerstertje:/# > >> > >> > >> > >> > >> System: > >> - Kernel 3.2.0 > >> - Debian Squeeze with: > >> ii e2fslibs 1.41.12-4stable1 ext2/ext3/ext4 file system libraries > >> ii e2fsprogs 1.41.12-4stable1 ext2/ext3/ext4 file system utilities > >> > >> ===8<===========End of original message text=========== > >> > >> > >> > >> -- > >> Best regards, > >> Sander mailto:linux@xxxxxxxxxxxxxx<Message01.eml> > > > > > -- > Best regards, > Sander mailto:linux@xxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html