Binary package hint: e2fsprogs
After a crash of Ubuntu netbook, the machine hang with initramfs (I
have a /boot and /).
Booting with the same system (ubuntu 10.10) from thumb drive, I cannot fsck it:
$ sudo fsck /dev/sda2
fsck from util-linux-ng 2.17.2
e2fsck 1.41.12 (17-May-2010)
fsck.ext4: Device or resource busy while trying to open /dev/sda2
Filesystem mounted or opened exclusively by another program?
But it is not mounted:
$ cat /proc/mounts
shows that it is not mounted; and it can't be unmounted.
dmesg knows what is going on:
$ dmesg | grep sda2
[ 6.513953] sda: sda1 [01;31m [Ksda2 [m [K sda3 < sda5 > sda4
[ 9.300388] EXT4-fs ( [01;31m [Ksda2 [m [K): INFO: recovery
required on readonly filesystem
[ 9.300398] EXT4-fs ( [01;31m [Ksda2 [m [K): write access will be
enabled during recovery
[ 9.312706] EXT4-fs warning (device [01;31m [Ksda2 [m [K):
ext4_clear_journal_err: Filesystem error recorded from previous mount:
IO failure
[ 9.312729] EXT4-fs warning (device [01;31m [Ksda2 [m [K):
ext4_clear_journal_err: Marking fs in need of filesystem check.
$
But this fsck does never materialise, and can't be done manually.
Finally, I tried to delete the journal, but to no avail, the "Device
or resource busy" stays. Is there any way to trick fsck into believing
me that it is not mounted?
If not, I still consider the behaviour somewhat wrong: if not in
/proc/mount, why does fsck say so?
And when I
sudo mount /dev/sda2 /mnt
it starts the mount process, but never finishes, and also it is
impossible to ever exit this process, I tried with Ctrl-C, Ctrl-Z, and
even with kill -9 from another console. Ubuntu isn't even able to shut
down then, but keeps trying forever.
In a nutshell, it is a bug in 10.10. I use the installer-CD written to the thumb drive (Startup Disk creator).
Confirmed: Because when I boot with a 9.04 thumb drive, I can easily open a terminal and run fsck. Done and over.
Same error, different circumstances:
# fsck.ext4 /dev/sde1
e2fsck 1.41.12 (17-May-2010)
fsck.ext4: Group descriptors look bad... trying backup blocks...
fsck.ext4: Bad magic number in super-block when using the backup blocks
fsck.ext4: going back to original superblock
fsck.ext4: Device or resource busy while trying to open /dev/sde1
Filesystem mounted or opened exclusively by another program?
The bug above is that the program opens /dev/sde1 once, forgets to close it,
then tries to open it a second time and fails. Found with strace:
[...]
write(1, "fsck.ext4: Group descriptors loo"..., 65) = 65
close(3) = 0
munmap(
open("/dev/sde1", O_RDWR|O_EXCL) = 3
ioctl(3, BLKROGET, 0x7fffe00b6bfc) = 0
uname({sys="Linux", node="idallen-
lseek(3, 134217728, SEEK_SET) = 134217728
read(3, "a%\20\
write(2, "fsck.ext4", 9) = 9
write(2, ": ", 2) = 2
write(2, "Bad magic number in super-block", 31) = 31
write(2, " ", 1) = 1
write(2, "when using the backup blocks", 28) = 28
ioctl(2, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(2, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
write(2, "\n", 1) = 1
write(1, "fsck.ext4: going back to origina"..., 45) = 45
open("/dev/sde1", O_RDWR|O_EXCL) = -1 EBUSY (Device or resource busy)
write(2, "fsck.ext4", 9) = 9
write(2, ": ", 2) = 2
write(2, "Device or resource busy", 23) = 23
write(2, " ", 1) = 1
write(2, "while trying to open /dev/sde1", 30) = 30
ioctl(2, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(2, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
write(2, "\n", 1) = 1
write(1, "Filesystem mounted or opened exc"..., 61) = 61
exit_group(8) = ?