Some more information. I can reproduce the crash always in the following way:
1) Boot the machine. 2) Log in to KDE. Everything works, including 3d effects. 3) Log out of KDE. KDM starts. 4) Log back in -> X crashes, KDM restarts immediately. 5) Log in again -> KDE disables 3d effects and allows logging in. Sometimes if I try to enable effects after 5), I can crash X again. But that does not happen every time. It also might be relevant that I can reproduce the crash on both my desktop machine and my laptop, both of which are running Oneiric and both of which have Intel integrated graphics. I have not seen similar behavior with my work desktop, which has discrete nVidia graphics. uname -a: Linux desktop 3.0.0-13-generic #22-Ubuntu SMP Wed Nov 2 13:27:26 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux lspci graphics information: 00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 12) Intel X driver version: 2:2.15.901-1ubuntu2.1 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/864010 Title: lightdm segfault in libglib after xorg segfault To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/864010/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs