Application: kwin (4.4.5 (KDE 4.4.5))
KDE Platform Version: 4.4.5 (KDE 4.4.5)
Qt Version: 4.6.3
Operating System: Linux 2.6.32-5-686 i686
Distribution: Debian GNU/Linux testing (squeeze)

-- Information about the crash:
I use Debian testing.

I was changing between windows, when the screen started to flicker, and all panels disappeared. After some time it all restarted, and everything was back to normal.

I had 2 firefox (iceweasel) windows in one group, and a java application window (Oracle SQL Developer). I was clicking on the window titles of the members of the group, to change to one, and to the other. I think I was trying to move the java window down a bit, to be able to see the firefox window titles.

After the crash, the firefox windows were no longer part of the group, and both were shaded.

 -- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
[KCrash Handler]
#6  KWin::ClientGroup::updateStates (this=0x8824538, main=0x8cc0328, only=0x0) at ../../kwin/clientgroup.cpp:285
#7  0xb76b30a5 in KWin::Client::setGeometry (this=0x8cc0328, x=0, y=0, w=1032, h=735, force=KWin::ForceGeometrySet) at ../../kwin/geometry.cpp:2046
#8  0xb76b4c24 in KWin::Client::setGeometry (this=0x8cc0328) at ../../kwin/client.h:885
#9  KWin::Client::resetMaximize (this=0x8cc0328) at ../../kwin/geometry.cpp:2438
#10 0xb76b9dd0 in KWin::Client::startMoveResize (this=0x8cc0328) at ../../kwin/geometry.cpp:2765
#11 0xb76ba1a0 in KWin::Client::handleMoveResize (this=0x8cc0328, x=387, y=39, x_root=358, y_root=10) at ../../kwin/geometry.cpp:2965
#12 0xb7684658 in KWin::Client::motionNotifyEvent (this=0x8cc0328, w=25983209, x=387, y=39, x_root=358, y_root=10) at ../../kwin/events.cpp:1498
#13 0xb76866b0 in KWin::Client::eventFilter (this=0x8cc0328, o=0x9095178, e=0xbff5ff84) at ../../kwin/events.cpp:1153
#14 0xb5d8476a in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=0x8784108, receiver=0x9095178, event=0xbff5ff84) at kernel/qcoreapplication.cpp:841
#15 0xb606d5a9 in QApplicationPrivate::notify_helper (this=0x8784108, receiver=0x9095178, e=0xbff5ff84) at kernel/qapplication.cpp:4298
#16 0xb6074af7 in QApplication::notify (this=0xbff60778, receiver=0x9095178, e=0xbff5ff84) at kernel/qapplication.cpp:3867
#17 0xb72e9bfa in KApplication::notify (this=0xbff60778, receiver=0x9095178, event=0xbff5ff84) at ../../kdeui/kernel/kapplication.cpp:302
#18 0xb765ef8f in KWin::Application::notify (this=0xbff60778, o=0x9095178, e=0xbff5ff84) at ../../kwin/main.cpp:370
#19 0xb5d854cb in QCoreApplication::notifyInternal (this=0xbff60778, receiver=0x9095178, event=0xbff5ff84) at kernel/qcoreapplication.cpp:726
#20 0xb6073a52 in QCoreApplication::sendEvent (receiver=0x9095178, event=0xbff5ff84, alienWidget=0x0, nativeWidget=0x9095178, buttonDown=0xb69b5998, lastMouseReceiver=..., spontaneous=true)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#21 QApplicationPrivate::sendMouseEvent (receiver=0x9095178, event=0xbff5ff84, alienWidget=0x0, nativeWidget=0x9095178, buttonDown=0xb69b5998, lastMouseReceiver=..., spontaneous=true)
    at kernel/qapplication.cpp:2967
#22 0xb60fed4c in QETWidget::translateMouseEvent (this=0x9095178, event=0xbff603d0) at kernel/qapplication_x11.cpp:4380
#23 0xb60fe253 in QApplication::x11ProcessEvent (this=0xbff60778, event=0xbff603d0) at kernel/qapplication_x11.cpp:3391
#24 0xb612c372 in x11EventSourceDispatch (s=0x8787340, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#25 0xb420e305 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#26 0xb4211fe8 in ?? () from /lib/libglib-2.0.so.0
#27 0xb42121c8 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#28 0xb5db1075 in QEventDispatcherGlib::processEvents (this=0x876e550, flags=...) at kernel/qeventdispatcher_glib.cpp:412
#29 0xb612bed5 in QGuiEventDispatcherGlib::processEvents (this=0x876e550, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#30 0xb5d83ae9 in QEventLoop::processEvents (this=0xbff606c4, flags=) at kernel/qeventloop.cpp:149
#31 0xb5d83f3a in QEventLoop::exec (this=0xbff606c4, flags=...) at kernel/qeventloop.cpp:201
#32 0xb5d8916f in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1003
#33 0xb606d667 in QApplication::exec () at kernel/qapplication.cpp:3581
#34 0xb7660aa0 in kdemain (argc=3, argv=0xbff60984) at ../../kwin/main.cpp:526
#35 0x0804860b in main (argc=3, argv=0xbff60984) at kwin_dummy.cpp:3

Possible duplicates by query: bug 238279.

Reported using DrKonqi