Re: [NOT FIXED] Re: umount2

[Russell King]

Alexander Viro writes:
> Not really. What actually triggered the sucker was negative dentry in the
> _middle_ of lookup. IOW, cat /foo/bar/baz and you've got a leak (unless
> you had both /foo and /foo/bar, that is).
> 
> Patch follows. Apply it, please. Folks, could you check whether it gets
> all work done? AFAICS it should, at least in that area. Anyway, bug
> is real and fix is obviously correct, so...
> 							Cheers,
> 								Al

I don't think your patch fixes every case.  It's certainly better, but I
just rebooted 2.3.99-pre5 with your patch applied, and had mount complaining
about /var busy while trying to reboot the machine.

After bootup, if I do the following:

(login as root)
# shutdown -t3 now
(wait for single user, kill off minilogd and kerneld if running - why kerneld???)
# ps ax
 -> shows init, kswapd, kflushd, kupdate, init, /bin/sh and ps ax running
# umount -av
none umounted
none umounted
/dev/hda6 umounted
/dev/hda5 umounted
umount: /var: device is busy
/dev/hda1 umounted
# mount
/dev/hda1 on / type ext2 (rw)
none on /proc  type proc (rw)
/dev/hda3 on /var type ext2 (rw)
# ls -al /proc/*/fd
(does not show anything located in /var)
# echo 1 > /proc/sys/kernel/sysrq
SysRq: Emergency Remount R/O
Remounting device 03:01 ... R/O
Remounting device 03:03 ... OK
Done.
# umount /var
umount: /var: device is busy

I am currently mounting (dubiously I know) shmfs on /var/shm.  Changing fstab
and rebooting such that shmfs gets mounted on /shm has no effect - I still end
up with /var busy.
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