Comment 157 for bug 1073433

You are definivly right in that case
a bug is allready opened(Bug #1073433 ) as i writing a comment to it
The normal user wants a clean shutdown or reboot and as I wrote its a dirty hack until this problem is resolved by the maintainers

we know the schutdown process isn't working correctly as i can see 154 comments on this issue
and the @S60umountroot proccess is definitivly just before reboot/shutdown process

and as i understand it in the right way
@S20sendsigs should stop all running (upstart) processes after that we can
@S31umountnfs.sh which is run before
@S40umountfs which runs before
@S60umountroot which expects that there are no more running processes (or open files)(otherwise we can't remount or unmount) left and at last runs (on a normal system nothing is between them)
@S90reboot

if there ane running processes at that moment that root is remountet or unmounted at shutdown or halt then fsck will complain on next boot.

you could check with adding /bin/ps aux >> /ps_schutdown.log just before line 86 in the /etc/rc6/@S60umountroot script as you can see then there are running processes just before the umount happens. sometimes it is NM(with dhcpclient and dnsmasq etc) but not always
i tried even adding a sleep 60 there to give the runnings some time to end but that wasn't working either because of the respawning ones

an killall5 -9 at that point shoulndt hurt because nfs and fs(tmpfs,run and so on) should be allready unmounted
plymouth is maybe the culprit if it because it stays alive till the bitter end so we have to kill it at this time
i dont mind to have a one or two second blackscreen just before the computer is off or reboots

an option could be that we load plymouth in to memory on shutdown so that there is no disk accces on shutdown

just my 2ct's on this