* /proc/mounts vs mount inconsistency in 2.6.16 (SLES10 SP1)
@ 2008-04-18 12:48 Ulrich Windl
0 siblings, 0 replies; only message in thread
From: Ulrich Windl @ 2008-04-18 12:48 UTC (permalink / raw)
To: linux-kernel
Hi,
I think I found a little problem in kernel 2.6.16.54-0.2.5-xen (Current SLES10
SP1):
By mistake I mounted some filesystem read-only over /.
Realizing the mistake, I did an "umount /", which seemed to work.
Then I noticed that / was mounted read-only, while the files being there were
those of the right root filesystem.
So I did a "Mount -o remount /" which enabled writes again.
As some other program had odd effects, I did "cat /proc/mounts" which still
displayed the wrong device and readonly (/dev/system/as2-root / reiserfs ro 0 0),
while umount refused to unmount it "umount: /dev/system/as2-root: not mounted".
It seems the interface between the mount/umount program and /proc/mounts is a bit
instable...
Some Details:
Device /dev/system/as2-root is mounted in the privileged domain,
and so cannot be mounted by a guest.
# mount
/dev/mapper/system-root on / type reiserfs (rw)
[...]
# cat /proc/mounts
rootfs / rootfs rw 0 0
[...]
/dev/system/as2-root / reiserfs ro 0 0
# umount /dev/system/as2-root
umount: /dev/system/as2-root: not mounted
# umount -f /dev/system/as2-root
umount2: Invalid argument
umount: /dev/system/as2-root: not mounted
# mount -o remount /dev/system/root / ### having looked it up in /etc/fstab
# cat /proc/mounts
rootfs / rootfs rw 0 0
[...]
/dev/system/as2-root / reiserfs ro 0 0
# mount /dev/system/root /
# cat /proc/mounts
rootfs / rootfs rw 0 0
[...]
/dev/system/as2-root / reiserfs ro 0 0
# umount / ### succeeds!
# mount /dev/system/root /
mount: /dev/system/root already mounted or / busy
mount: according to mtab, /dev/mapper/system-root is already mounted on /
# cat /proc/mounts
rootfs / rootfs rw 0 0
[...]
/dev/system/as2-root / reiserfs ro 0 0
/dev/system/root / reiserfs ro 0 0
# xm create -c as2
Using config file "/etc/xen/vm/as2".
Error: Device 2049 (vbd) could not be connected.
Device /dev/system/as2-root is mounted in the privileged domain,
and so cannot be mounted by a guest.
S**t: Isn't there a solution other than rebooting Dom0 (XEN talk)?
Regards,
Ulrich
P.S. I'm not subscribed to the kernel list, so if you want to reach me, please CC:
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2008-04-18 13:08 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2008-04-18 12:48 /proc/mounts vs mount inconsistency in 2.6.16 (SLES10 SP1) Ulrich Windl
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).