If any devs want info out of my drive, please ask today, I really need to fix it tomorrow. I'll try btrfs-zero-log otherwise and if not, wipe and start over. Marc On Thu, Oct 25, 2012 at 12:58:05PM -0700, Marc MERLIN wrote: > Howdy, > > I can wait a day or maybe 2 before I have to wipe and restore from backup. > Please let me know if you have a patch against 3.6.3 you'd like me to try > to mount/recover this filesystem, or whether you'd like me to try btrfsck. > > > My laptop had a problem with its boot drive which prevented linux > from writing to it, and in turn caused btrfs to have incomplete writes > to it. > After reboot, the boot drive was fine, but the btrfs filesystem has > a corruption that prevents it from being mounted. > > Unfortunately the mount crash prevents writing of crash data to even another > drive since linux stops before the crash data can be written to syslog. > > Picture #1 shows a dump when my laptop crashed (before reboot). > btrfs no csum found for inode X start Y > http://marc.merlins.org/tmp/crash.jpg > > Mounting with 3.5.0 and 3.6.3 gives the same error: > > gandalfthegreat:~# mount -o recovery,skip_balance,ro /dev/mapper/bootdsk > > shows > btrfs: bdev /dev/mapper/bootdsk errs: wr 0, rd 0, flush 0, corrupt 1, gen 0 > btrfs: bdev /dev/mapper/bootdsk errs: wr 0, rd 0, flush 0, corrupt 2, gen 0 > (there are 2 lines, not sure why) > > kernel BUG at fs/btrfs/volumes.c:3707 > int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len) > { > struct extent_map *em; > struct map_lookup *map; > struct extent_map_tree *em_tree = &map_tree->map_tree; > int ret; > > read_lock(&em_tree->lock); > em = lookup_extent_mapping(em_tree, logical, len); > read_unlock(&em_tree->lock); > BUG_ON(!em); <--- > > If the snapshot helps (sorry, hard to read, but usable): > http://marc.merlins.org/tmp/btrfs_bug.jpg > > Questions: > 1) Any better way to get a proper dump without serial console? > (I hate to give you pictures) > > 2) Should I try btrfsck now, or are there other mount options than > mount -o recovery,skip_balance,ro /dev/mapper/bootdsk > I should try? > > 3) Want me to try btrfsck although it may make it impossible for me to > reproduce the bug and test a fix, as well as potentially break the filesystem > more (last time I tried btrfsck, it outputted thousands of lines and never converged > to a state it was happy with) > > Thanks, > Marc > -- > "A mouse is a device used to point at the xterm you want to type in" - A.S.R. > Microsoft is to operating systems .... > .... what McDonalds is to gourmet cooking > Home page: http://marc.merlins.org/ > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
