Thursday, January 5, 2012, 7:15:35 PM, you wrote: > 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 Also found some old info that might be related, http://answers.softpicks.net/answers/topic/2-6-28-ext4-xen-and-lvm-volume-becomes-ro-after-snapshot-1610734-1.htm I'm also running under xen (host only, no guests started), will try baremetal as well to see if that plays a role. -- Sander >> >> [ 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 -- Best regards, Sander mailto:linux@xxxxxxxxxxxxxx -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel