Application: plasma-desktop (0.3)
KDE Platform Version: 4.3.98 (KDE 4.3.98 (KDE 4.4 RC3)) (Compiled from sources)
Qt Version: 4.6.1
Operating System: Linux 2.6.31-zen13-rt20 x86_64
Distribution (Platform): Gentoo Packages

-- Information about the crash:
I tried to use Plasma's widget dashboard. Compiz has a focus bug with it, so the 'native' dialogs appear underneath. I removed several widgets, then tried to select 'download new widgets', but it was stuck 'underneath', so when I cancelled the dashboard, Plasma crashed.

 -- Backtrace:
Application: Plasma Workspace (plasma-desktop), signal: Segmentation fault
Traceback (most recent call last):
  File "/usr/share/gdb/auto-load/usr/lib64/libgobject-2.0.so.0.2200.4-gdb.py", line 9, in <module>
    from gobject import register
  File "/usr/share/glib-2.0/gdb/gobject.py", line 3, in <module>
    import gdb.backtrace
ImportError: No module named backtrace
The current source language is "auto; currently asm".
[Current thread is 1 (Thread 0x7f1fdcd54780 (LWP 8849))]

Thread 3 (Thread 0x7f1fc52f3710 (LWP 8854)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00000039aa9e67e6 in WTF::TCMalloc_PageHeap::scavengerThread (this=<value optimized out>) at ../JavaScriptCore/wtf/FastMalloc.cpp:2299
#2  0x00000039aa9e6809 in WTF::TCMalloc_PageHeap::runScavengerThread (context=<value optimized out>) at ../JavaScriptCore/wtf/FastMalloc.cpp:1433
#3  0x0000003996c07547 in start_thread (arg=<value optimized out>) at pthread_create.c:297
#4  0x00000039964d581d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f1fc337c710 (LWP 21196)):
#0  pthread_cond_timedwait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:211
#1  0x000000399d47b0e7 in QWaitConditionPrivate::wait (this=<value optimized out>, mutex=<value optimized out>, time=<value optimized out>) at thread/qwaitcondition_unix.cpp:85
#2  QWaitCondition::wait (this=<value optimized out>, mutex=<value optimized out>, time=<value optimized out>) at thread/qwaitcondition_unix.cpp:159
#3  0x000000399d470151 in QThreadPoolThread::run (this=<value optimized out>) at concurrent/qthreadpool.cpp:140
#4  0x000000399d47a225 in QThreadPrivate::start (arg=<value optimized out>) at thread/qthread_unix.cpp:248
#5  0x0000003996c07547 in start_thread (arg=<value optimized out>) at pthread_create.c:297
#6  0x00000039964d581d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f1fdcd54780 (LWP 8849)):
[KCrash Handler]
#5  QGraphicsItemPrivate::invalidateGraphicsEffectsRecursively (this=<value optimized out>) at graphicsview/qgraphicsitem.cpp:5033
#6  0x00000039a072f135 in QGraphicsItem::update (this=<value optimized out>, rect=<value optimized out>) at graphicsview/qgraphicsitem.cpp:5285
#7  0x00007f1fcbdf7dbf in QGraphicsItem::update (sipSelf=0x1f9f050, sipArgs=0x182e050, sipKwds=0x0) at /usr/include/qt4/QtGui/qgraphicsitem.h:495
#8  meth_QGraphicsItem_update (sipSelf=0x1f9f050, sipArgs=0x182e050, sipKwds=0x0) at sipQtGuiQGraphicsItem.cpp:2835
#9  0x00007f1fccc85b76 in call_function (f=<value optimized out>, throwflag=<value optimized out>) at Python/ceval.c:3706
#10 PyEval_EvalFrameEx (f=<value optimized out>, throwflag=<value optimized out>) at Python/ceval.c:2389
#11 0x00007f1fccc873c4 in PyEval_EvalCodeEx (co=<value optimized out>, globals=<value optimized out>, locals=<value optimized out>, args=<value optimized out>, argcount=<value optimized out>, 
    kws=<value optimized out>, kwcount=) at Python/ceval.c:2968
#12 0x00007f1fccc1b03f in function_call (func=<value optimized out>, arg=<value optimized out>, kw=<value optimized out>) at Objects/funcobject.c:524
#13 0x00007f1fccbf3fc2 in PyObject_Call (func=<value optimized out>, arg=<value optimized out>, kw=<value optimized out>) at Objects/abstract.c:2492
#14 0x00007f1fccc0643d in instancemethod_call (func=<value optimized out>, arg=<value optimized out>, kw=<value optimized out>) at Objects/classobject.c:2579
#15 0x00007f1fccbf3fc2 in PyObject_Call (func=<value optimized out>, arg=<value optimized out>, kw=<value optimized out>) at Objects/abstract.c:2492
#16 0x00007f1fccc7f9c2 in PyEval_CallObjectWithKeywords (func=<value optimized out>, arg=<value optimized out>, kw=<value optimized out>) at Python/ceval.c:3575
#17 0x00007f1fcc32a6d8 in sip_api_invoke_slot (slot=0x191af40, sigargs=0x182e050) at qtlib.c:191
#18 0x00007f1fcc6c3fd6 in PyQtProxy::invokeSlot (slot=..., qargs=0x7fff53849f00) at qpycore_pyqtproxy.cpp:474
#19 0x00007f1fcc6c40e8 in PyQtProxy::unislot (this=0x191af10, qargs=0x7fff53849f00) at qpycore_pyqtproxy.cpp:416
#20 0x00007f1fcc6c41c5 in PyQtProxy::qt_metacall (this=0x191af10, _c=QMetaObject::InvokeMetaMethod, _id=24264816, _a=0x7fff53849f00) at qpycore_pyqtproxy.cpp:380
#21 0x000000399d584477 in QMetaObject::activate (sender=<value optimized out>, m=<value optimized out>, local_signal_index=<value optimized out>, argv=<value optimized out>)
    at kernel/qobject.cpp:3267
#22 0x00007f1fcc5ed0d3 in sipQTimer::timerEvent (this=0x1f8c740, a0=0x7fff5384a7b0) at sipQtCoreQTimer.cpp:153
#23 0x000000399d580e63 in QObject::event (this=<value optimized out>, e=<value optimized out>) at kernel/qobject.cpp:1204
#24 0x00007f1fcc5ed063 in sipQTimer::event (this=0x1f8c740, a0=0x7fff5384a7b0) at sipQtCoreQTimer.cpp:170
#25 0x00000039a01bbded in QApplicationPrivate::notify_helper (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:4298
#26 0x00000039a01c4e23 in QApplication::notify (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:3702
#27 0x00000039a122a876 in KApplication::notify (this=<value optimized out>, receiver=<value optimized out>, event=<value optimized out>)
    at /var/tmp/portage/kde-base/kdelibs-4.3.98/work/kdelibs-4.3.98/kdeui/kernel/kapplication.cpp:302
#28 0x000000399d570c3b in QCoreApplication::notifyInternal (this=<value optimized out>, receiver=<value optimized out>, event=<value optimized out>) at kernel/qcoreapplication.cpp:704
#29 0x000000399d59ecd4 in QCoreApplication::sendEvent (this=<value optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#30 QTimerInfoList::activateTimers (this=<value optimized out>) at kernel/qeventdispatcher_unix.cpp:603
#31 0x000000399d59b548 in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#32 idleTimerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:231
#33 0x0000003998c3b4ed in g_main_dispatch (context=<value optimized out>) at gmain.c:1960
#34 IA__g_main_context_dispatch (context=<value optimized out>) at gmain.c:2513
#35 0x0000003998c3eea8 in g_main_context_iterate (context=<value optimized out>, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>) at gmain.c:2591
#36 0x0000003998c3efd0 in IA__g_main_context_iteration (context=<value optimized out>, may_block=<value optimized out>) at gmain.c:2654
#37 0x000000399d59b21c in QEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#38 0x00000039a025a37f in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#39 0x000000399d56f532 in QEventLoop::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventloop.cpp:149
#40 0x000000399d56f904 in QEventLoop::exec (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventloop.cpp:201
#41 0x000000399d571dd6 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#42 0x00007f1fddcd9902 in kdemain (argc=<value optimized out>, argv=<value optimized out>)
    at /var/tmp/portage/kde-base/plasma-workspace-4.3.98/work/plasma-workspace-4.3.98/plasma/desktop/shell/main.cpp:112
#43 0x000000399641eba6 in __libc_start_main (main=<value optimized out>, argc=<value optimized out>, ubp_av=<value optimized out>, init=<value optimized out>, fini=<value optimized out>, 
    rtld_fini=<value optimized out>, stack_end=) at libc-start.c:220
#44 0x00000000004007a9 in _start ()

Reported using DrKonqi