Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.2 (KDE 4.3.2)
Qt Version: 4.5.2
Operating System: Linux 2.6.31-17-generic i686
Distribution: Ubuntu 9.10

What I was doing when the application crashed:
I had added several of the System Monitor* applets to my panel. I had added the "System Monitor" (subtitle - "System monitoring applet") and was interacting with it. Suddenly the screen went black and then I got the message that KDE had crashed.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0xb7785700 (LWP 30183))]

Thread 2 (Thread 0xac66fb70 (LWP 30184)):
#0  0x00591422 in __kernel_vsyscall ()
#1  0x00135e15 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0x008b387d in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0x0029be67 in QWaitConditionPrivate::wait (this=0x94105e8, mutex=0x94105e4, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#4  QWaitCondition::wait (this=0x94105e8, mutex=0x94105e4, time=4294967295) at thread/qwaitcondition_unix.cpp:159
#5  0x041ea922 in QHostInfoAgent::run (this=0x94105d8) at kernel/qhostinfo.cpp:260
#6  0x0029ae32 in QThreadPrivate::start (arg=0x94105d8) at thread/qthread_unix.cpp:188
#7  0x0013180e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#8  0x008a68de in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb7785700 (LWP 30183)):
[KCrash Handler]
#6  Plasma::Containment::containmentType (this=0xac314c0) at ../../plasma/containment.cpp:418
#7  0x07ea23c3 in ?? () from /usr/lib/kde4/plasma_applet_system-monitor.so
#8  0x07ea2d6d in ?? () from /usr/lib/kde4/plasma_applet_system-monitor.so
#9  0x07ea2ea8 in ?? () from /usr/lib/kde4/plasma_applet_system-monitor.so
#10 0x003a1263 in QMetaObject::activate (sender=0xac1b980, from_signal_index=8, to_signal_index=8, argv=0xbff0a808) at kernel/qobject.cpp:3113
#11 0x003a1ec2 in QMetaObject::activate (sender=0xac1b980, m=0x78c563c, local_signal_index=1, argv=0xbff0a808) at kernel/qobject.cpp:3187
#12 0x0780a6a9 in Plasma::PushButton::toggled (this=0xac1b980, _t1=false) at ./pushbutton.moc:140
#13 0x0780bf20 in Plasma::PushButton::qt_metacall (this=0xac1b980, _c=QMetaObject::InvokeMetaMethod, _id=1, _a=0xbff0a998) at ./pushbutton.moc:85
#14 0x07ea4d4a in MonitorButton::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/kde4/plasma_applet_system-monitor.so
#15 0x003a1263 in QMetaObject::activate (sender=0xac1b4c8, from_signal_index=31, to_signal_index=31, argv=0xbff0a998) at kernel/qobject.cpp:3113
#16 0x003a1ec2 in QMetaObject::activate (sender=0xac1b4c8, m=0x2c130a4, local_signal_index=4, argv=0xbff0a998) at kernel/qobject.cpp:3187
#17 0x02a2cbe9 in QAbstractButton::toggled (this=0xac1b4c8, _t1=false) at .moc/release-shared/moc_qabstractbutton.cpp:207
#18 0x027574f4 in QAbstractButton::setChecked (this=0xac1b4c8, checked=false) at widgets/qabstractbutton.cpp:763
#19 0x02757680 in QAbstractButton::nextCheckState (this=0xac1b4c8) at widgets/qabstractbutton.cpp:1017
#20 0x02757163 in QAbstractButtonPrivate::click (this=0xa993910) at widgets/qabstractbutton.cpp:525
#21 0x02757431 in QAbstractButton::mouseReleaseEvent (this=0xac1b4c8, e=0xac59e98) at widgets/qabstractbutton.cpp:1115
#22 0x023f5012 in QWidget::event (this=0xac1b4c8, event=0xac59e98) at kernel/qwidget.cpp:7549
#23 0x027553ee in QAbstractButton::event (this=0xac1b4c8, e=0x0) at widgets/qabstractbutton.cpp:1077
#24 0x027ff66d in QPushButton::event (this=0xac1b4c8, e=0xac59e98) at widgets/qpushbutton.cpp:662
#25 0x0239ff54 in QApplicationPrivate::notify_helper (this=0x8e56128, receiver=0xac1b4c8, e=0xac59e98) at kernel/qapplication.cpp:4056
#26 0x023a8033 in QApplication::notify (this=0x8e2f2b0, receiver=0xac1b4c8, e=0xac59e98) at kernel/qapplication.cpp:3758
#27 0x00fb7bfa in KApplication::notify (this=0x8e2f2b0, receiver=0xac1b4c8, event=0xac59e98) at ../../kdeui/kernel/kapplication.cpp:302
#28 0x0038b6cb in QCoreApplication::notifyInternal (this=0x8e2f2b0, receiver=0xac1b4c8, event=0xac59e98) at kernel/qcoreapplication.cpp:610
#29 0x023a6f6e in QCoreApplication::sendSpontaneousEvent (receiver=0xac1b4c8, event=0xac59e98, alienWidget=0x0, nativeWidget=0xac1b4c8, buttonDown=0xbff0b01c, lastMouseReceiver=...)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#30 QApplicationPrivate::sendMouseEvent (receiver=0xac1b4c8, event=0xac59e98, alienWidget=0x0, nativeWidget=0xac1b4c8, buttonDown=0xbff0b01c, lastMouseReceiver=...) at kernel/qapplication.cpp:2924
#31 0x02a0d1b5 in QGraphicsProxyWidgetPrivate::sendWidgetMouseEvent (this=0xa341920, event=0xbff0b69c) at graphicsview/qgraphicsproxywidget.cpp:278
#32 0x029ab8bc in QGraphicsItem::sceneEvent (this=0xac1b988, event=0xbff0b69c) at graphicsview/qgraphicsitem.cpp:5030
#33 0x029f89ef in QGraphicsWidget::sceneEvent (this=0xac1b980, event=0xbff0b69c) at graphicsview/qgraphicswidget.cpp:1110
#34 0x029cde14 in QGraphicsScenePrivate::sendEvent (this=0x8f2c310, item=0xac1b988, event=0xbff0b69c) at graphicsview/qgraphicsscene.cpp:1159
#35 0x029cf443 in QGraphicsScenePrivate::sendMouseEvent (this=0x8f2c310, mouseEvent=0xbff0b69c) at graphicsview/qgraphicsscene.cpp:1230
#36 0x029da344 in QGraphicsScene::mouseReleaseEvent (this=0x8f1b090, mouseEvent=0xbff0b69c) at graphicsview/qgraphicsscene.cpp:4445
#37 0x029dbf87 in QGraphicsScene::event (this=0x8f1b090, event=0xbff0b69c) at graphicsview/qgraphicsscene.cpp:3808
#38 0x0239ff54 in QApplicationPrivate::notify_helper (this=0x8e56128, receiver=0x8f1b090, e=0xbff0b69c) at kernel/qapplication.cpp:4056
#39 0x023a767c in QApplication::notify (this=0x8e2f2b0, receiver=0x8f1b090, e=0xbff0b69c) at kernel/qapplication.cpp:3603
#40 0x00fb7bfa in KApplication::notify (this=0x8e2f2b0, receiver=0x8f1b090, event=0xbff0b69c) at ../../kdeui/kernel/kapplication.cpp:302
#41 0x0038b6cb in QCoreApplication::notifyInternal (this=0x8e2f2b0, receiver=0x8f1b090, event=0xbff0b69c) at kernel/qcoreapplication.cpp:610
#42 0x029edb1e in QCoreApplication::sendEvent (this=0x9665ef8, event=0xbff0bcc0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#43 QGraphicsView::mouseReleaseEvent (this=0x9665ef8, event=0xbff0bcc0) at graphicsview/qgraphicsview.cpp:3382
#44 0x023f5012 in QWidget::event (this=0x9665ef8, event=0xbff0bcc0) at kernel/qwidget.cpp:7549
#45 0x027a4633 in QFrame::event (this=0x9665ef8, e=0xbff0bcc0) at widgets/qframe.cpp:559
#46 0x02843494 in QAbstractScrollArea::viewportEvent (this=0x6, e=0x0) at widgets/qabstractscrollarea.cpp:962
#47 0x029ed51f in QGraphicsView::viewportEvent (this=0x9665ef8, event=0xbff0bcc0) at graphicsview/qgraphicsview.cpp:2919
#48 0x02845a95 in QAbstractScrollAreaPrivate::viewportEvent (this=0x9d93ef8, o=0xab947a8, e=0xbff0bcc0) at widgets/qabstractscrollarea_p.h:100
#49 QAbstractScrollAreaFilter::eventFilter (this=0x9d93ef8, o=0xab947a8, e=0xbff0bcc0) at widgets/qabstractscrollarea_p.h:111
#50 0x0038a83a in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=0x8e56128, receiver=0xab947a8, event=0xbff0bcc0) at kernel/qcoreapplication.cpp:726
#51 0x0239ff2c in QApplicationPrivate::notify_helper (this=0x8e56128, receiver=0xab947a8, e=0xbff0bcc0) at kernel/qapplication.cpp:4052
#52 0x023a8033 in QApplication::notify (this=0x8e2f2b0, receiver=0xab947a8, e=0xbff0bcc0) at kernel/qapplication.cpp:3758
#53 0x00fb7bfa in KApplication::notify (this=0x8e2f2b0, receiver=0xab947a8, event=0xbff0bcc0) at ../../kdeui/kernel/kapplication.cpp:302
#54 0x0038b6cb in QCoreApplication::notifyInternal (this=0x8e2f2b0, receiver=0xab947a8, event=0xbff0bcc0) at kernel/qcoreapplication.cpp:610
#55 0x023a6f6e in QCoreApplication::sendSpontaneousEvent (receiver=0xab947a8, event=0xbff0bcc0, alienWidget=0xab947a8, nativeWidget=0xab85be8, buttonDown=0x2c1aaa0, lastMouseReceiver=...)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#56 QApplicationPrivate::sendMouseEvent (receiver=0xab947a8, event=0xbff0bcc0, alienWidget=0xab947a8, nativeWidget=0xab85be8, buttonDown=0x2c1aaa0, lastMouseReceiver=...)
    at kernel/qapplication.cpp:2924
#57 0x024157c0 in QETWidget::translateMouseEvent (this=0xab85be8, event=0xbff0d30c) at kernel/qapplication_x11.cpp:4409
#58 0x02414c4b in QApplication::x11ProcessEvent (this=0x8e2f2b0, event=0xbff0d30c) at kernel/qapplication_x11.cpp:3428
#59 0x02441502 in x11EventSourceDispatch (s=0x8e58d68, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#60 0x001b4e88 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#61 0x001b8730 in ?? () from /lib/libglib-2.0.so.0
#62 0x001b8863 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#63 0x003b602c in QEventDispatcherGlib::processEvents (this=0x8e55f18, flags=...) at kernel/qeventdispatcher_glib.cpp:327
#64 0x02440be5 in QGuiEventDispatcherGlib::processEvents (this=0x8e55f18, flags=...) at kernel/qguieventdispatcher_glib.cpp:202
#65 0x00389c79 in QEventLoop::processEvents (this=0xbff0d604, flags=) at kernel/qeventloop.cpp:149
#66 0x0038a0ca in QEventLoop::exec (this=0xbff0d604, flags=...) at kernel/qeventloop.cpp:201
#67 0x0038c53f in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#68 0x0239fdd7 in QApplication::exec () at kernel/qapplication.cpp:3525
#69 0x013d280d in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#70 0x0804dde1 in launch (argc=<value optimized out>, _name=<value optimized out>, args=<value optimized out>, cwd=0x0, envc=0, envs=0x8e18558 "", reset_env=false, tty=0x0, avoid_loops=false, 
    startup_id_str=0x80511a5 "0") at ../../kinit/kinit.cpp:677
#71 0x0804ea35 in handle_launcher_request (sock=<value optimized out>, who=<value optimized out>) at ../../kinit/kinit.cpp:1169
#72 0x0804eeac in handle_requests (waitForPid=<value optimized out>) at ../../kinit/kinit.cpp:1362
#73 0x0804fbaf in main (argc=2, argv=0xbff0de64, envp=0xbff0de70) at ../../kinit/kinit.cpp:1793

Reported using DrKonqi