kwin crashes on startup after upgrade to 11.2

I upgraded from 11.0 to 11.2 on my Dell Inspiron 6000 with an ATI Mobility M300 graphics card.

I get the crash handler, it says kwin has crashed multiple times, and it asks me to choose another window manager. After choosing Metacity “most” everything works fine, but there are a few anomalys that I wonder if are because kwin is not running.

Here is the available (and insufficient) backtrace.

Application: KWin (kwin), signal: Aborted
[KCrash Handler]
#6  0xffffe424 in __kernel_vsyscall ()
#7  0xb74f00cf in raise () from /lib/libc.so.6
#8  0xb74f19e7 in abort () from /lib/libc.so.6
#9  0xb74e8efe in __assert_fail () from /lib/libc.so.6
#10 0xb6d3b326 in _XRead () from /usr/lib/libX11.so.6
#11 0xb6ca4b39 in ?? () from /usr/X11R6/lib/libGL.so.1
Backtrace stopped: previous frame inner to this frame (corrupt stack?)

I have searched for the debug files related to libGL so I can get more backtrace info to no avail. Any help here?

This began happening immediately after the upgrade. I have recently upgraded my ATI/Catalyst driver to 9.11 and no change.
(although, as a side note which should be another thread, I can’t run the ATI Catalyst Control Center.)

Main thing is what do I need to get further backtrace info?

I tried disabling 3D and did not help.

also…it crashes also when I try and go to Personal Settings >> Look & Feel >> Desktop >> Desktop Effects

and gives these added backtrace info…

Application: System Settings (systemsettings), signal: Aborted
[Current thread is 1 (Thread 0xb563c700 (LWP 5768))]

Thread 2 (Thread 0xaffa1b70 (LWP 9887)):
#0  0xffffe424 in __kernel_vsyscall ()
#1  0xb5ede0c2 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2  0xb63202d4 in pthread_cond_timedwait () from /lib/libc.so.6
#3  0xb64e36dc in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQtCore.so.4
#4  0xb64d8bc2 in ?? () from /usr/lib/libQtCore.so.4
#5  0xb64e2623 in ?? () from /usr/lib/libQtCore.so.4
#6  0xb5ed96e5 in start_thread () from /lib/libpthread.so.0
#7  0xb5ed9600 in ?? () from /lib/libpthread.so.0

Thread 1 (Thread 0xb563c700 (LWP 5768)):
[KCrash Handler]
#6  0xffffe424 in __kernel_vsyscall ()
#7  0xb626b0cf in raise () from /lib/libc.so.6
#8  0xb626c9e7 in abort () from /lib/libc.so.6
#9  0xb6263efe in __assert_fail () from /lib/libc.so.6
#10 0xb5dbe326 in _XRead () from /usr/lib/libX11.so.6
#11 0xaf4fcb39 in ?? () from /usr/X11R6/lib/libGL.so.1
Backtrace stopped: previous frame inner to this frame (corrupt stack?)