Application: kwin (4.11.9)
KDE Platform Version: 4.13.0
Qt Version: 4.8.6
Operating System: Linux 3.13.0-24-generic i686
Distribution: Ubuntu 14.04 LTS

-- Information about the crash:
The system (probably Plasma Desktop) was completely unresponsive, so I hit [Ctrl][Alt]F1 and issued a reboot command.  When the system returned, I noticed none of my applications relaunched.  I started Thunderbird & Firefox successfully, and was opening Konsole windows on various desktops and setting their "special window settings."

I had set this on three Konsole windows when the crash occurred.

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0xb118b980 (LWP 2317))]

Thread 2 (Thread 0xaa48cb40 (LWP 2333)):
#0  0xb77b0424 in __kernel_vsyscall ()
#1  0xb4c85d4b in pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/i386/i686/../i486/pthread_cond_wait.S:187
#2  0xb753f8ec in __pthread_cond_wait (cond=0xb70688d0, mutex=0xb70688b8) at forward.c:149
#3  0xb6f65c92 in ?? () from /usr/lib/i386-linux-gnu/libQtScript.so.4
#4  0xb6f65cdf in ?? () from /usr/lib/i386-linux-gnu/libQtScript.so.4
#5  0xb4c81f70 in start_thread (arg=0xaa48cb40) at pthread_create.c:312
#6  0xb753270e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129

Thread 1 (Thread 0xb118b980 (LWP 2317)):
[KCrash Handler]
#7  contains (t=@0xbf867154: 0x8bc6478, this=0x8c5efac) at ../../include/QtCore/../../src/corelib/tools/qlist.h:882
#8  QActionGroup::addAction (this=0x8c20d40, a=a@entry=0x8bc6478) at kernel/qactiongroup.cpp:180
#9  0xb769f524 in KWin::UserActionsMenu::activityPopupAboutToShow (this=0x83f8988) at ../../kwin/useractions.cpp:723
#10 0xb763ccd0 in KWin::UserActionsMenu::qt_static_metacall (_o=0xb0, _id=-1240527632, _a=0xbf867288, _c=<optimized out>) at moc_useractions.cpp:81
#11 0xb5f9b0f7 in QMetaObject::activate (sender=sender@entry=0x883daf0, m=m@entry=0xb5df2e94 <QMenu::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3539
#12 0xb5930995 in QMenu::aboutToShow (this=this@entry=0x883daf0) at .moc/release-shared/moc_qmenu.cpp:164
#13 0xb59340fb in QMenu::popup (this=0x883daf0, p=..., atAction=atAction@entry=0x0) at widgets/qmenu.cpp:1844
#14 0xb5935a4d in QMenu::internalDelayedPopup (this=this@entry=0x8c0dfb8) at widgets/qmenu.cpp:3057
#15 0xb59377d6 in QMenu::timerEvent (this=0x8c0dfb8, e=0xbf8678c0) at widgets/qmenu.cpp:2917
#16 0xb5f9f55c in QObject::event (this=0x8c0dfb8, e=0xbf8678c0) at kernel/qobject.cpp:1156
#17 0xb54eb452 in QWidget::event (this=this@entry=0x8c0dfb8, event=event@entry=0xbf8678c0) at kernel/qwidget.cpp:8846
#18 0xb593a2af in QMenu::event (this=0x8c0dfb8, e=0xbf8678c0) at widgets/qmenu.cpp:2481
#19 0xb54917f4 in QApplicationPrivate::notify_helper (this=0x8366160, receiver=0x8c0dfb8, e=0xbf8678c0) at kernel/qapplication.cpp:4567
#20 0xb54982d3 in QApplication::notify (this=0xbf868728, receiver=receiver@entry=0x8c0dfb8, e=e@entry=0xbf8678c0) at kernel/qapplication.cpp:4353
#21 0xb6bb60a4 in KApplication::notify (this=this@entry=0xbf868728, receiver=receiver@entry=0x8c0dfb8, event=event@entry=0xbf8678c0) at ../../kdeui/kernel/kapplication.cpp:311
#22 0xb76735f9 in KWin::Application::notify (this=0xbf868728, o=0x8c0dfb8, e=0xbf8678c0) at ../../kwin/main.cpp:431
#23 0xb5f85e4a in QCoreApplication::notifyInternal (this=0xbf868728, receiver=0x8c0dfb8, event=event@entry=0xbf8678c0) at kernel/qcoreapplication.cpp:953
#24 0xb5fb87bb in sendEvent (event=0xbf8678c0, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#25 QTimerInfoList::activateTimers (this=0x8366aac) at kernel/qeventdispatcher_unix.cpp:621
#26 0xb5fb8835 in QEventDispatcherUNIX::activateTimers (this=<optimized out>, this@entry=0x8324eb8) at kernel/qeventdispatcher_unix.cpp:878
#27 0xb5fb90bc in QEventDispatcherUNIX::processEvents (this=this@entry=0x8324eb8, flags=...) at kernel/qeventdispatcher_unix.cpp:940
#28 0xb554706b in QEventDispatcherX11::processEvents (this=0x8324eb8, flags=...) at kernel/qeventdispatcher_x11.cpp:152
#29 0xb5f84823 in QEventLoop::processEvents (this=this@entry=0xbf867ae8, flags=...) at kernel/qeventloop.cpp:149
#30 0xb5f84b49 in QEventLoop::exec (this=this@entry=0xbf867ae8, flags=...) at kernel/qeventloop.cpp:204
#31 0xb5938e7f in QMenu::exec (this=0x8c0dfb8, p=..., action=action@entry=0x0) at widgets/qmenu.cpp:2125
#32 0xb769ba59 in KWin::UserActionsMenu::show (this=0x83f8988, pos=..., cl=...) at ../../kwin/useractions.cpp:179
#33 0xb769bbac in KWin::Workspace::showWindowMenu (this=0x83f8820, pos=..., cl=0x8c6b4a0) at ../../kwin/useractions.cpp:1827
#34 0xb768de22 in KWin::Bridge::showWindowMenu (this=0x881ca28, p=...) at ../../kwin/bridge.cpp:115
#35 0xb743265a in KDecoration::showWindowMenu (this=0x8b99a50, pos=...) at ../../../kwin/libkdecorations/kdecoration.cpp:222
#36 0xb7439376 in KCommonDecoration::showWindowMenu (this=this@entry=0x8bb5770, pos=...) at ../../../kwin/libkdecorations/kcommondecoration.cpp:1211
#37 0xb7439431 in KCommonDecoration::doShowWindowMenu (this=this@entry=0x8bb5770) at ../../../kwin/libkdecorations/kcommondecoration.cpp:788
#38 0xb743b262 in KCommonDecoration::menuButtonPressed (this=0x8bb5770) at ../../../kwin/libkdecorations/kcommondecoration.cpp:752
#39 0xb743b578 in KCommonDecoration::qt_static_metacall (_o=<optimized out>, _id=<optimized out>, _a=0xbf867d28, _c=<optimized out>) at ./kcommondecoration.moc:102
#40 0xb5f9b0f7 in QMetaObject::activate (sender=sender@entry=0x8c5b338, m=m@entry=0xb5dffac8 <QAbstractButton::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3539
#41 0xb5b8e015 in QAbstractButton::pressed (this=this@entry=0x8c5b338) at .moc/release-shared/moc_qabstractbutton.cpp:206
#42 0xb58a8b61 in QAbstractButtonPrivate::emitPressed (this=this@entry=0x8a03b70) at widgets/qabstractbutton.cpp:562
#43 0xb58a9232 in QAbstractButton::mousePressEvent (this=this@entry=0x8c5b338, e=e@entry=0xbf867e18) at widgets/qabstractbutton.cpp:1098
#44 0xb743d0b4 in KCommonDecorationButton::mousePressEvent (this=this@entry=0x8c5b338, e=e@entry=0xbf868284) at ../../../kwin/libkdecorations/kcommondecoration.cpp:1106
#45 0xadfb11d1 in Oxygen::Button::mousePressEvent (this=0x8c5b338, event=0xbf868284) at ../../../../kwin/clients/oxygen/oxygenbutton.cpp:224
#46 0xb54eb1e3 in QWidget::event (this=this@entry=0x8c5b338, event=event@entry=0xbf868284) at kernel/qwidget.cpp:8372
#47 0xb58aaf42 in QAbstractButton::event (this=0x8c5b338, e=0xbf868284) at widgets/qabstractbutton.cpp:1082
#48 0xb54917f4 in QApplicationPrivate::notify_helper (this=0x8366160, receiver=receiver@entry=0x8c5b338, e=0xbf868284) at kernel/qapplication.cpp:4567
#49 0xb5499ea0 in QApplication::notify (this=0xbf868728, receiver=receiver@entry=0x8c5b338, e=e@entry=0xbf868284) at kernel/qapplication.cpp:4110
#50 0xb6bb60a4 in KApplication::notify (this=this@entry=0xbf868728, receiver=receiver@entry=0x8c5b338, event=event@entry=0xbf868284) at ../../kdeui/kernel/kapplication.cpp:311
#51 0xb76735f9 in KWin::Application::notify (this=0xbf868728, o=0x8c5b338, e=0xbf868284) at ../../kwin/main.cpp:431
#52 0xb5f85e4a in QCoreApplication::notifyInternal (this=0xbf868728, receiver=receiver@entry=0x8c5b338, event=event@entry=0xbf868284) at kernel/qcoreapplication.cpp:953
#53 0xb5497b53 in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#54 QApplicationPrivate::sendMouseEvent (receiver=receiver@entry=0x8c5b338, event=0xbf868284, alienWidget=0x0, nativeWidget=0x8c5b338, buttonDown=buttonDown@entry=0xb5e08ce4 <qt_button_down>, lastMouseReceiver=..., spontaneous=spontaneous@entry=true) at kernel/qapplication.cpp:3178
#55 0xb551b778 in QETWidget::translateMouseEvent (this=0x8c5b338, event=event@entry=0xbf8684ac) at kernel/qapplication_x11.cpp:4634
#56 0xb551aec5 in QApplication::x11ProcessEvent (this=0xbf868728, event=event@entry=0xbf8684ac) at kernel/qapplication_x11.cpp:3627
#57 0xb5546ff5 in QEventDispatcherX11::processEvents (this=0x8324eb8, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#58 0xb5f84823 in QEventLoop::processEvents (this=this@entry=0xbf868628, flags=...) at kernel/qeventloop.cpp:149
#59 0xb5f84b49 in QEventLoop::exec (this=this@entry=0xbf868628, flags=...) at kernel/qeventloop.cpp:204
#60 0xb5f8a8fe in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1225
#61 0xb548fa24 in QApplication::exec () at kernel/qapplication.cpp:3828
#62 0xb767499e in kdemain (argc=1, argv=0xbf868814) at ../../kwin/main.cpp:597
#63 0x0804855b in main (argc=1, argv=0xbf868814) at kwin_dummy.cpp:3

Possible duplicates by query: bug 335244, bug 334539, bug 334152.

Reported using DrKonqi