Comment # 2 on bug 930357 from Dominique Leuenberger

My next one to tackle...

After studying the journal of failed and successful boots, it becomes apparent
that in failed state:

- starting service gdm... done
happens WAY after X already died on us.. which means: 'something' else (which
does not know about logind!) started X for us beforehand, resulting in the
permission denied error.

The log also shows "Started X Display Manager", which indicates xdm.service has
been started up.