Application: plasma-desktop (0.4)
KDE Platform Version: 4.5.95 (4.6 RC2)
Qt Version: 4.7.1
Operating System: Linux 2.6.37-12-generic x86_64
Distribution: Ubuntu natty (development branch)

-- Information about the crash:
When I try to add a task manager widget to either the desktop or the bottom panel, plasma crahes.

I've tried both the stock "task manager" widget as well as the "smooth tasks" widget (for its crash the backtrace was generated).

The crash can be reproduced every time.

-- Backtrace:
Application: Plasma Desktop Shell (plasma-desktop), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f26d5bfd7a0 (LWP 6072))]

Thread 3 (Thread 0x7f26b54a0700 (LWP 6073)):
#0  0x00007f26ca82140e in __pthread_mutex_lock (mutex=0x1835c38) at pthread_mutex_lock.c:62
#1  0x00007f26c9f1db70 in g_main_context_dispatch (context=0x1835c30) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3009
#2  0x00007f26c9f1e4f8 in g_main_context_iterate (context=0x1835c30, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3091
#3  0x00007f26c9f1e789 in g_main_context_iteration (context=0x1835c30, may_block=1) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3154
#4  0x00007f26d2937a26 in QEventDispatcherGlib::processEvents (this=0x1835230, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:417
#5  0x00007f26d290bed2 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007f26d290c10c in QEventLoop::exec (this=0x7f26b549fdb0, flags=...) at kernel/qeventloop.cpp:201
#7  0x00007f26d2823214 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:490
#8  0x00007f26d28ee3df in QInotifyFileSystemWatcherEngine::run (this=0x1826430) at io/qfilesystemwatcher_inotify.cpp:248
#9  0x00007f26d28259ce in QThreadPrivate::start (arg=0x1826430) at thread/qthread_unix.cpp:285
#10 0x00007f26ca81ed8c in start_thread (arg=0x7f26b54a0700) at pthread_create.c:304
#11 0x00007f26d551161d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#12 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f26b4c9f700 (LWP 6074)):
#0  0x00007f26d55044b3 in __poll (fds=<value optimized out>, nfds=<value optimized out>, timeout=<value optimized out>) at ../sysdeps/unix/sysv/linux/poll.c:87
#1  0x00007f26c9f1e260 in g_main_context_poll (context=0x1840b40, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3404
#2  g_main_context_iterate (context=0x1840b40, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3086
#3  0x00007f26c9f1e789 in g_main_context_iteration (context=0x1840b40, may_block=1) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3154
#4  0x00007f26d2937a26 in QEventDispatcherGlib::processEvents (this=0x1839af0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:417
#5  0x00007f26d290bed2 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007f26d290c10c in QEventLoop::exec (this=0x7f26b4c9edc0, flags=...) at kernel/qeventloop.cpp:201
#7  0x00007f26d2823214 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:490
#8  0x00007f26c826013c in Herqq::Upnp::HControlPointThread::run() () from /usr/lib/libHUpnp.so.0
#9  0x00007f26d28259ce in QThreadPrivate::start (arg=0x183a5e0) at thread/qthread_unix.cpp:285
#10 0x00007f26ca81ed8c in start_thread (arg=0x7f26b4c9f700) at pthread_create.c:304
#11 0x00007f26d551161d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#12 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f26d5bfd7a0 (LWP 6072)):
[KCrash Handler]
#6  0x00007f26d1aeb1d0 in vtable for __cxxabiv1::__si_class_type_info () from /usr/lib/libstdc++.so.6
#7  0x00007f26d227c5fe in QGraphicsItem::dragLeaveEvent (this=0x22c79c0, event=0x1) at graphicsview/qgraphicsitem.cpp:6836
#8  0x00007f26d1d10471 in focusNextChild (this=0x2319210, enable=false) at ../../include/QtGui/../../src/gui/kernel/qwidget.h:710
#9  QWidgetPrivate::setEnabled_helper (this=0x2319210, enable=false) at kernel/qwidget.cpp:3245
#10 0x00007f26d22a73dc in QGraphicsProxyWidget::itemChange (this=0x23134b0, change=<value optimized out>, value=<value optimized out>) at graphicsview/qgraphicsproxywidget.cpp:818
#11 0x00007f26d2294ef5 in QGraphicsItemPrivate::setEnabledHelper (this=0x2317090, newEnabled=false, explicitly=<value optimized out>, update=<value optimized out>) at graphicsview/qgraphicsitem.cpp:2522
#12 0x00007f26d510d723 in syncToAction (this=0x23134b0, _c=<value optimized out>, _id=10, _a=0x7ffff3694950) at ../../plasma/private/actionwidgetinterface_p.h:60
#13 clearAction (this=0x23134b0, _c=<value optimized out>, _id=10, _a=0x7ffff3694950) at ../../plasma/private/actionwidgetinterface_p.h:51
#14 Plasma::PushButton::qt_metacall (this=0x23134b0, _c=<value optimized out>, _id=10, _a=0x7ffff3694950) at ./pushbutton.moc:115
#15 0x00007f26d43d7a30 in CategoriesWidget::qt_metacall (this=0x23134b0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7ffff3694950) at moc_appletsfiltering.cpp:74
#16 0x00007f26d2921bb8 in QMetaObject::activate (sender=0x202a330, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x7ffff3694950) at kernel/qobject.cpp:3280
#17 0x00007f26d29220cf in QObject::destroyed (this=<value optimized out>, _t1=0x202a330) at .moc/release-shared/moc_qobject.cpp:149
#18 0x00007f26d29237b7 in QObject::~QObject (this=0x202a330, __in_chrg=<value optimized out>) at kernel/qobject.cpp:842
#19 0x00007f26d1cb616b in QAction::~QAction (this=0x202a330, __in_chrg=<value optimized out>) at kernel/qaction.cpp:652
#20 0x00007f26d1cb61b9 in QAction::~QAction (this=0x202a330, __in_chrg=<value optimized out>) at kernel/qaction.cpp:676
#21 0x00007f26d291f1e4 in QObjectPrivate::deleteChildren (this=0x2324700) at kernel/qobject.cpp:1957
#22 0x00007f26d1d09cf2 in QWidget::~QWidget (this=0x2325c70, __in_chrg=<value optimized out>) at kernel/qwidget.cpp:1600
#23 0x00007f26d20f9959 in QMenu::~QMenu (this=0x2325c70, __in_chrg=<value optimized out>) at widgets/qmenu.cpp:1405
#24 0x00007f26d43f8286 in CategoriesWidget::~CategoriesWidget (this=0x23134b0, __in_chrg=<value optimized out>) at ../../../libs/plasmagenericshell/widgetsexplorer/appletsfiltering.cpp:62
#25 0x00007f26d43f82b9 in CategoriesWidget::~CategoriesWidget (this=0x23134b0, __in_chrg=<value optimized out>) at ../../../libs/plasmagenericshell/widgetsexplorer/appletsfiltering.cpp:63
#26 0x00007f26d229642c in QGraphicsItem::~QGraphicsItem (this=0x22c79d0, __in_chrg=<value optimized out>) at graphicsview/qgraphicsitem.cpp:1481
#27 0x00007f26d22e5f58 in ~QGraphicsObject (this=0x22c79c0, __in_chrg=<value optimized out>) at ../../include/QtGui/../../src/gui/graphicsview/qgraphicsitem.h:547
#28 QGraphicsWidget::~QGraphicsWidget (this=0x22c79c0, __in_chrg=<value optimized out>) at graphicsview/qgraphicswidget.cpp:232
#29 0x00007f26d43f9489 in FilteringWidget::~FilteringWidget (this=0x22c79c0, __in_chrg=<value optimized out>) at ../../../libs/plasmagenericshell/widgetsexplorer/appletsfiltering.cpp:154
#30 0x00007f26d229642c in QGraphicsItem::~QGraphicsItem (this=0x2118210, __in_chrg=<value optimized out>) at graphicsview/qgraphicsitem.cpp:1481
#31 0x00007f26d22e5f58 in ~QGraphicsObject (this=0x2118200, __in_chrg=<value optimized out>) at ../../include/QtGui/../../src/gui/graphicsview/qgraphicsitem.h:547
#32 QGraphicsWidget::~QGraphicsWidget (this=0x2118200, __in_chrg=<value optimized out>) at graphicsview/qgraphicswidget.cpp:232
#33 0x00007f26d43fe439 in Plasma::WidgetExplorer::~WidgetExplorer (this=0x2118200, __in_chrg=<value optimized out>) at ../../../libs/plasmagenericshell/widgetsexplorer/widgetexplorer.cpp:282
#34 0x00007f26d57e3ac1 in ControllerWindow::~ControllerWindow (this=0x1f376e0, __in_chrg=<value optimized out>) at ../../../../plasma/desktop/shell/controllerwindow.cpp:113
#35 0x00007f26d57f67b9 in PanelController::~PanelController (this=0x1f376e0, __in_chrg=<value optimized out>) at ../../../../plasma/desktop/shell/panelcontroller.cpp:240
#36 0x00007f26d2920a78 in QObject::event (this=0x1f376e0, e=<value optimized out>) at kernel/qobject.cpp:1202
#37 0x00007f26d1d0e48d in QWidget::event (this=0x1f376e0, event=0x26ed8d0) at kernel/qwidget.cpp:8659
#38 0x00007f26d1cbdb24 in QApplicationPrivate::notify_helper (this=0x13b0e80, receiver=0x1f376e0, e=0x26ed8d0) at kernel/qapplication.cpp:4445
#39 0x00007f26d1cc245a in QApplication::notify (this=<value optimized out>, receiver=0x1f376e0, e=0x26ed8d0) at kernel/qapplication.cpp:4324
#40 0x00007f26d35c36d6 in KApplication::notify (this=0x139a230, receiver=0x1f376e0, event=0x26ed8d0) at ../../kdeui/kernel/kapplication.cpp:311
#41 0x00007f26d290caec in QCoreApplication::notifyInternal (this=0x139a230, receiver=0x1f376e0, event=0x26ed8d0) at kernel/qcoreapplication.cpp:732
#42 0x00007f26d2910275 in sendEvent (receiver=0x0, event_type=0, data=0x134f7d0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#43 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x134f7d0) at kernel/qcoreapplication.cpp:1373
#44 0x00007f26d2937833 in sendPostedEvents (s=0x13b36a0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:220
#45 postEventSourceDispatch (s=0x13b36a0) at kernel/qeventdispatcher_glib.cpp:277
#46 0x00007f26c9f1dd0d in g_main_dispatch (context=0x13b35b0) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:2440
#47 g_main_context_dispatch (context=0x13b35b0) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3013
#48 0x00007f26c9f1e4f8 in g_main_context_iterate (context=0x13b35b0, block=<value optimized out>, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3091
#49 0x00007f26c9f1e789 in g_main_context_iteration (context=0x13b35b0, may_block=1) at /build/buildd/glib2.0-2.27.90/glib/gmain.c:3154
#50 0x00007f26d29379cf in QEventDispatcherGlib::processEvents (this=0x13b0c70, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:415
#51 0x00007f26d1d63a9e in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#52 0x00007f26d290bed2 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#53 0x00007f26d290c10c in QEventLoop::exec (this=0x7ffff3695950, flags=...) at kernel/qeventloop.cpp:201
#54 0x00007f26d291051b in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1009
#55 0x00007f26d57f25d7 in kdemain (argc=1, argv=0x7ffff3695d18) at ../../../../plasma/desktop/shell/main.cpp:118
#56 0x00007f26d544fd1e in __libc_start_main (main=0x400740 <main(int, char**)>, argc=1, ubp_av=0x7ffff3695d18, init=<value optimized out>, fini=<value optimized out>, rtld_fini=<value optimized out>, stack_end=0x7ffff3695d08) at libc-start.c:226
#57 0x0000000000400669 in _start ()

Possible duplicates by query: bug 262494, bug 262302.

Reported using DrKonqi