no login possible, xserver crash when pressing login

[Thomas]

Binary package hint: gdm

Once I press the login button, the whole xserver is restarted before I can enter a username. Login is only possible via kdm.
There is always a new xserver started when this happens. The old server remains active with only a cursor visible. I had no problem with gdm prior the latest updates.

Hint: To get kdm started I go to a console and stop gdm there.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: gdm 2.30.2.is.2.30.2-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.35-7.11-generic-pae 2.6.35-rc4
Uname: Linux 2.6.35-7-generic-pae i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Thu Jul 8 20:27:33 2010
ProcEnviron:
 LANGUAGE=en_US:en
 PATH=(custom, user)
 LANG=en_US.utf8
 SHELL=/usr/bin/zsh
SourcePackage: gdm

[Thomas (t-hartwig)]

The logfile of gdm is not very helpful I am afraid.

[Sebastien Bacher (seb128)]

thank you for your bug report, what version did you use before the upgrade? what change did you do to the configuration?

[Thomas (t-hartwig)]

I can not say for sure what version I had before. But I downgraded to version 2.30.0-0ubuntu5 now to test and this version works fine. I did not tune anything in the configuration.

[Sebastien Bacher (seb128)]

could you describe what you do on the user screen? what users are listed and how you select those?

[Thomas (t-hartwig)]

I have the standard gdm greeter with only a login button. Once I press this usually the login field appears to enter a username. But If I press this button now the whole xserver restarts. Sometimes it crashes and a new instance on the same screen 0 is started. Sometimes it is started in a consecutive screen and the old one only remains with a cursor in it.

[Sebastien Bacher (seb128)]

the standard greeter directly list users, are you sure you didn't change the config?

[Thomas (t-hartwig)]

I upgraded from Lucid Lynx some while ago. Don't remember to have forced any special setting. Which configuration is responsible for the user list layout?

[Sebastien Bacher (seb128)]

it seems that could be bug #585574

[Sebastien Bacher (seb128)]

bug #579044 rather

[Thomas (t-hartwig)]

Indeed https://bugs.launchpad.net/bugs/579044 looks extremely similar, however I never did disable user listing nor do I have such setting in my gconf files. But the result seems to be the same. Somehow I do not have a user list and this results in a crash. Further more a have no custom.conf which was removed to fix the issue. But will look deeper into the system now if I can find an old setting somewhere. Please feel free to duplicate my report.

[Thomas (t-hartwig)]

Ok, found the problem. I have an uid of 500 for me. This is for historical reasons to be compatible with any backups. So I had the user list feature already enabled but by default only users with an uid of 1000 and above have been listed in the new gdm. This is why I had only the login button visible (there have been no users with that high uid in my system). However the "old" gdm seemed to go around this and prompted me for a user since it got no valid user when I pressed the login button. The newest release seems to dislike this and simply crashes.

[Sebastien Bacher (seb128)]

duplicate from bug #579044 then