ext3_clear_journal_err: Filesystem error recorded from previous mount

Hi,

this MacMini (x86, 2.6.24-24-xen) has an external disk attached via 
Firewire. Earlier today, the disk had a problem (might be the disk, but 
could've been the cabling, I suspect the latter) and the kernel rightfully 
complained about it:

sd 4:0:0:0: [sdb] Result: hostbyte=DID_BUS_BUSY driverbyte=DRIVER_OK,SUGGEST_OK
end_request: I/O error, dev sdb, sector 366464538

This sdb holds LVM volumes and one volume (/dev/mapper/vault) is usually 
mounted 'ro'. When the backup script tried to mount it 'rw', this happened:

--------------------------------------------------------
kjournald starting.  Commit interval 5 seconds
EXT3-fs: mounted filesystem with ordered data mode.
__journal_remove_journal_head: freeing b_committed_data
__journal_remove_journal_head: freeing b_committed_data
WARNING: at /data/Scratch/scm/hardy-git/debian/build/custom-source-xen/fs/buffer.c:1169 mark_buffer_dirty()
Pid: 20378, comm: umount Not tainted 2.6.24-24-xen #1
Call Trace:
 [<ffffffff802cf147>] mark_buffer_dirty+0x87/0xa0
 [<ffffffff880f0702>] :jbd:journal_update_superblock+0x82/0x100
 [<ffffffff880f0b9c>] :jbd:journal_destroy+0x18c/0x1f0
 [<ffffffff802508c0>] autoremove_wake_function+0x0/0x30
 [<ffffffff88109709>] :ext3:ext3_put_super+0x29/0x210
 [<ffffffff802a8e3a>] generic_shutdown_super+0x6a/0x120
 [<ffffffff802a8efd>] kill_block_super+0xd/0x20
 [<ffffffff802a8fe4>] deactivate_super+0x74/0xb0
 [<ffffffff802c156b>] sys_umount+0x6b/0x2f0
 [<ffffffff802aaae7>] sys_newstat+0x27/0x50
 [<ffffffff80292c6e>] do_munmap+0x2de/0x340
 [<ffffffff8034a081>] __up_write+0x21/0x150
 [<ffffffff8020c818>] system_call+0x68/0x6d
 [<ffffffff8020c7b0>] system_call+0x0/0x6d
EXT3-fs: INFO: recovery required on readonly filesystem.
EXT3-fs: write access will be enabled during recovery.
kjournald starting.  Commit interval 5 seconds
EXT3-fs warning (device dm-31): ext3_clear_journal_err: Filesystem error recorded from previous mount: IO failure
EXT3-fs warning (device dm-31): ext3_clear_journal_err: Marking fs in need of filesystem check.
EXT3-fs: recovery complete.
EXT3-fs: mounted filesystem with ordered data mode.
-------------------------------------------------------- 

However, even after unmounting, running e2fsck on the filesystem in 
question the "Filesystem error recorded from previous mount: IO failure" 
message persists. Is this expected behaviour or could the WARNING somehow 
have confused the kernel (and the ext3 module)? I can still mount the fs, even 
'rw', but the errors in the log are kinda disturbing....

I've put the full log on: 

   http://nerdbynature.de/bits/2.6.24-24-xen/e2fsck-20100525.txt

Thanks,
Christian.
-- 
BOFH excuse #114:

electro-magnetic pulses from French above ground nuke testing.