System hangs on login immediately after logout

[Carsten Agger]

We're running Ubuntu 12.04.

The bug occurs with a number of PC running a kiosk-like setup with password-free login. The desktop is standard Unity.

Scenario:

* User arrives at PC in library.
* User finds active session and wants to log out to get a fresh session.
* User logs out
* User *immediately* presses button to login
* System hangs.

The "system hanging" is like this: Desktop icons are present, but the launcher is gone, and the top bar with the time and command menus (including the logout menu) is also gone.

The only way out (bar hitting the power button) is to enter CTRL-ALT-DEL, which opens a logout dialog. You can now choose to logout, wait a while and login again.

It *seems* to be caused by the very swift sequence of logout + login.

It's annoying and thus a serious bug, since it's very confusing to transient users, of which we have a lot.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Robert Ancell (robert-ancell)]

Could you please attach /var/log/lightdm/lightdm.log after this occurs? This will show if it is lightdm causing the problem or the session is just not completing logout.

[Launchpad Janitor (janitor)]

[Expired for lightdm (Ubuntu) because there has been no activity for 60 days.]

[Carsten Agger (agger)]

The correct thing to do would probably be to check of the problem can be reproduced in 14.04.