Comment 22 for bug 579858

On Sat, 2011-01-22 at 18:57 +0000, Paul Crawford wrote:
> I did a couple of tests yesterday on my automounted nfs share, and it appeared to have fixed the segfault there.
> However, today when I shut down I pressed 'Esc' to see the messages and I got a very brief glimpse of a message about the / mount being busy, maybe something else (can't say if it was a segfault message) and then the machine powered off immediately. On restarting, I found messages in syslog about orphaned inodes in the root file system, THAT IS BAD!
> My own system is running 32-bit 10.04 and I have separate partitions for /, /tmp, and /home, so most likely the file(s) in use for / were log messages (pulseaudio is particularly bad at loads of pointless rate limiting messages, etc, and I had been doing stuff with sound). But there is no excuse for not unmounting properly!
> Given the report of Etienne Goyer, and my experience today, there is clearly something still not correct about umount.
>

Paul, is it possible that you hit bug #672177, which causes / to not be
unmountable whenever upstart or libc6 is upgraded?

As to your hypothesis that it was logs, rsyslog *should* be stopped by
the time /etc/init.d/umountroot runs, though there's actually no
guarantee as the SIGTERM is sent/received/executed in parallel with the
rest of the shutdown. That is bug #688541, but I think sounds less
likely.