/etc/init.d/gdm stop fails and falsely reports success

[Stoic Jed]

Binary package hint: gdm

Trying to stop gdm gives the following:

$ /etc/init.d/gdm stop
  * Stopping GNOME Display Manager... [ ok ]

Should there instead be an error message, since gdm is not actually stopped?

Using gdm version 2.14.6-0ubuntu2 on Ubuntu Dapper.

[Sebastien Bacher (seb128)]

Thanks for your bug. I've just tried on a bunch of softwares from init.d and several have that issue, that might be something to change to the lsb-base package

[Mitch Hollander (mitch00)]

This is also the case when using sudo, i.e.,
"sudo /etc/init.d/gdm stop". And by extension, affects "restart" as well.

The main problem is that it prevents the user from restarting gdm without rebooting - necessary when trying to solve xorg problems on the Live CD.

"killall -HUP gdm" can be used as a workaround.

[Tormod Volden (tormodvolden)]

> that might be something to change to the lsb-base package

Yes, it's a problem with the arguments given to the start-stop-daemon. IIRC, leaving out the --exec argument makes --stop work.

This is still a problem in Feisty, after running "sudo /etc/init.d/gdm stop", the two gdm processes keep running.

[Tormod Volden (tormodvolden)]

Verified on Feisty that removing --exec makes it work. Additionally, the --oknodo argument to start-stop-daemon makes the script return success even if it did not kill gdm.

I guess start-stop-daemon should just ignore the --exec argument when --stop is present? At least not just ignore everything and quit.

OTOH if this is expected behavior from start-stop-daemon, many init scripts must be fixed.

[Tormod Volden (tormodvolden)]

Sorry for the confusion and my misinformed guesses. start-stop-daemon uses the --exec argument to double-check it will kill the right process.

The problem on the live cd is that start-stop-daemon tries to match the --exec argument /usr/sbin/gdm with /proc/<pid>/exe (where <pid> is the correct pid from the /var/run/gdm.pid). On the live cd, /proc/<pid>/exe contains "/rofs/usr/sbin/gdm" instead of "/usr/sbin/gdm".

I don't know if this should be fixed in start-stop-daemon (by relaxing the --exec file name matching and relying on inode number matching) or in casper.

[Steve Magoun (smagoun)]

This affects Ubuntu Mobile as well. Ubuntu Mobile uses unionfs to merge a squashfs image and an ext3 partition. /proc/<pid>/exe points to /squashmnt/path/to/exe rather than /path/to/exe, so start-stop-daemon --exec never finds a running process.

In Ubuntu Mobile the problem can be worked around by 'ln -s / /squashmnt', yuck.

[lee321987 (reiterwill77)]

Can someone please tell me the location of the file that contains the "--exec command" that I have to remove in order to be able to stop gdm on a live CD?
I assume I'll just need to delete the characters "--exec". Is this true?