I think I got some similar bug on Kubuntu 12.04.
It happens randomly.
I found this in /var/kdm.log
Backtrace:
0: /usr/bin/X (xorg_backtrace+0x37) [0xb7749627]
1: /usr/bin/X (0xb75c1000+0x18c3aa) [0xb774d3aa]
2: (vdso) (__kernel_rt_sigreturn+0x0) [0xb759e40c]
3: /usr/lib/dri/fglrx_dri.so (0xb19e0000+0xae36c5) [0xb24c36c5]
Segmentation fault at address (nil)
Caught signal 11 (Segmentation fault). Server aborting
Please consult the The X.Org Foundation support
at http://wiki.x.org
for help.
Please also check the log file at "/var/log/Xorg.0.log" for additional
information.
ddxSigGiveUp: Closing log
Server terminated with error (1). Closing log file.
X.Org X Server 1.11.3
Release Date: 2011-12-16
X Protocol Version 11, Revision 0
Build Operating System: Linux 2.6.42-26-generic i686 Ubuntu
There's also an entry in /var/syslog:
Aug 22 17:42:07 x86 kdm[1153]: X server for display :0 terminated unexpectedly
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which is subscribed to xorg-server in Ubuntu.
https://bugs.launchpad.net/bugs/740785
Title:
Caught signal 11 (Segmentation fault). Server aborting
To manage notifications about this bug go to:
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