Kernel Panic for File System, cannot umount / fsck

[Tim Harding <tim.harding@gmail.com>]

Hello all,

I've just received the kernel panic below while performing an rf on
/home/backup.

I can read /home.  I can't write to /home.  I can't umount /home or
kill the processing blocking that umount.  I can't run fsck.  How can
I recover from this situation?

Details follow this message.  I'd really appreciate some help.

Thanks, -Tim

The machine:
clark:/home# uname -a
Linux clark 2.4.20 #1 SMP Mon May 19 22:13:40 CDT 2003 i686 unknown

Some disk type stuff:
clark:/home# mount
/dev/md0 on / type ext3 (rw,errors=remount-ro)
proc on /proc type proc (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/md1 on /boot type ext3 (rw)
/dev/md2 on /home type ext3 (rw)

clark:/home# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md0               18G  2.5G   14G  15% /
/dev/md1               45M  7.2M   36M  17% /boot
/dev/md2               54G  2.8G   48G   6% /home


In /var/log/kern.log

Jan 18 15:29:14 clark kernel: EXT3-fs error (device md(9,2)):
ext3_free_blocks: Freeing blocks not in datazone - block = 1768125184,
count = 1
Jan 18 15:29:14 clark kernel: EXT3-fs error (device md(9,2)):
ext3_free_blocks: Freeing blocks not in datazone - block = 1769238117,
count = 1
Jan 18 15:29:14 clark kernel: EXT3-fs error (device md(9,2)):
ext3_free_blocks: bit already cleared for block 7629158
Jan 18 15:29:14 clark kernel: EXT3-fs error (device md(9,2)):
ext3_free_blocks: bit already cleared for block 3932159
Jan 18 15:29:14 clark kernel: Kernel panic: EXT3-fs panic (device
md(9,2)): load_block_bitmap: block_group >= groups_count - block_group
= 131071, groups_count = 444

While trying to rm -rf /home/backup I that error occurred.

The terminal session suspended.

I cannot kill or kill -9 or kill -STOP that rm -rf /home/backup.  The
kill fails silently, the process remains in the process list.

I cannot write to home:
clark:/home# touch /home/tim/foo
touch: creating `/home/tim/foo': Read-only file system

I cannot umount /home:
clark:/home# umount /home
umount: /home: device is busy

I would like to fsck /home but:
clark:/home# fsck /home
fsck 1.27 (8-Mar-2002)
e2fsck 1.27 (8-Mar-2002)
/dev/md2 is mounted.  

WARNING!!!  Running e2fsck on a mounted filesystem may cause
SEVERE filesystem damage.

Do you really want to continue (y/n)? no

check aborted.


Once again, thanks.