Application: kwin (4.9.1)
KDE Platform Version: 4.9.1
Qt Version: 4.8.2
Operating System: Linux 3.2.0-31-generic x86_64
Distribution: Ubuntu 12.04.1 LTS

-- Information about the crash:
- What I was doing when the application crashed:

Login via NX session. This has not been happening in Kubuntu 11.10 but started happening in Kubuntu 12.04.

- Custom settings of the application:

None

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[KCrash Handler]
#6  mUSABLe (mem=0x1) at malloc.c:4651
#7  __malloc_usable_size (m=0x1) at malloc.c:3379
#8  0x00007fbd31a05563 in ?? () from /usr/lib/nvidia-current/libGL.so.1
#9  0x00007fbd29d8bcc1 in ?? () from /usr/lib/nvidia-current/tls/libnvidia-tls.so.304.51
#10 0x00007fbd333c2819 in XFree () from /usr/lib/x86_64-linux-gnu/libX11.so.6
#11 0x00007fbd32f6a2ee in XRRUpdateConfiguration () from /usr/lib/x86_64-linux-gnu/libXrandr.so.2
#12 0x00007fbd35678c96 in KWin::Workspace::workspaceEvent (this=0xedc7f0, e=0x7fff3d9473b0) at ../../kwin/events.cpp:461
#13 0x00007fbd35669e48 in KWin::Application::x11EventFilter (this=0x7fff3d947680, e=0x7fff3d9473b0) at ../../kwin/main.cpp:362
#14 0x00007fbd3029eaa5 in qt_x11EventFilter (ev=0x7fff3d9473b0) at kernel/qapplication_x11.cpp:441
#15 qt_x11EventFilter (ev=0x7fff3d9473b0) at kernel/qapplication_x11.cpp:429
#16 0x00007fbd302adeb8 in QApplication::x11ProcessEvent (this=0x7fff3d947680, event=0x7fff3d9473b0) at kernel/qapplication_x11.cpp:3444
#17 0x00007fbd302d8aba in QEventDispatcherX11::processEvents (this=0xcedad0, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#18 0x00007fbd30eace42 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#19 0x00007fbd30ead097 in QEventLoop::exec (this=0x7fff3d947600, flags=...) at kernel/qeventloop.cpp:204
#20 0x00007fbd30eb23e7 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1187
#21 0x00007fbd3566c4f3 in kdemain (argc=<optimized out>, argv=<optimized out>) at ../../kwin/main.cpp:545
#22 0x00007fbd3526c76d in __libc_start_main (main=0x400630 <main(int, char**)>, argc=1, ubp_av=0x7fff3d947d78, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff3d947d68) at libc-start.c:226
#23 0x0000000000400661 in _start ()

Possible duplicates by query: bug 307023, bug 300515, bug 298845, bug 293209.

Reported using DrKonqi