Bug#504389:

[Tim Richardson]

Notes:
1) from the login window, rebooting and shutdown works as expected.
Splashy is invoked.  

2) after doing /etc/init.d/gdm stop, this process remains gconfd-2
I've ignored this. bt didn't look interesting. 

3) after logging in and rebooting via the gdm System menu, the reboot
stops. Here is a one of those annoying non-developer guesses: It appears
that gdm is waiting for splashy (?), and patch 52 perhaps stops
terminations of gdm that used to happen from the reboot process? For
some reason on intel graphics, splashy is waiting for vt8 to be
activated, but this block doesn't happen on non-intel video hardware
such as virtual machines or nvidia. 

Virtual terminal 1 shows nothing at all, just a blank screen with a
flashing cursor. 
 
One of the virtual terminals shows output from the shutdown.
INIT: Switching to runlevel: 6
INIT: Sending processes the TERM signal [ok]
* Stopping GNOME Display manger gdm [ok]

and no more activity.

(switching to vt8 wakes up splashy and the reboot continues. )

3a) However, after logging in, starting a gnome terminal and doing
sudo reboot
the reboot works correctly


4)  I attached gdb to gdm after logging in. From gdm I restarted via the
System menu, as usual.
Control comes back to gdm at various points; I kept doing "continue"
because I don't know what I am looking for. 
And the restart worked; that is, the terminal was auto switched to vt8
and splashy ran.  Twice it happened, so while using gdb, I can't
reproduce it.