Application: kwin_x11 (5.3.0)

Qt Version: 5.4.1
Operating System: Linux 3.19.0-18-generic x86_64
Distribution: Ubuntu 15.04

-- Information about the crash:
- What I was doing when the application crashed:
System settings > hardware > Display and Monitor > enabled external monitor and disabled the laptop screen or vice versa

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f5cd5b38800 (LWP 2222))]

Thread 6 (Thread 0x7f5cb45fd700 (LWP 2225)):
#0  0x00007f5cd56068dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f5ccc691ebc in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f5ccc692242 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f5cbcaa4ae6 in ?? () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#4  0x00007f5ccc6b8955 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f5cd4e876aa in start_thread (arg=0x7f5cb45fd700) at pthread_create.c:333
#6  0x00007f5cd5611eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7f5cb3dfc700 (LWP 2226)):
#0  0x00007f5cd560249d in read () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f5ccc6d52f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f5ccc69196c in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f5ccc691e60 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f5ccc691fcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f5ccc692009 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007f5ccc6b8955 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#7  0x00007f5cd4e876aa in start_thread (arg=0x7f5cb3dfc700) at pthread_create.c:333
#8  0x00007f5cd5611eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7f5cb1b93700 (LWP 2250)):
#0  0x00007f5cd3bd6e64 in QMetaObject::activate (sender=sender@entry=0x7f5ca00008c0, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3593
#1  0x00007f5cd3bd7057 in QMetaObject::activate (sender=sender@entry=0x7f5ca00008c0, m=m@entry=0x7f5cd3e000a0 <QAbstractEventDispatcher::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3582
#2  0x00007f5cd3c55cc0 in QAbstractEventDispatcher::aboutToBlock (this=this@entry=0x7f5ca00008c0) at .moc/moc_qabstracteventdispatcher.cpp:134
#3  0x00007f5cd3bfc186 in QEventDispatcherUNIX::processEvents (this=0x7f5ca00008c0, flags=...) at kernel/qeventdispatcher_unix.cpp:587
#4  0x00007f5cd3ba33e2 in QEventLoop::exec (this=this@entry=0x7f5cb1b92da0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#5  0x00007f5cd3962b44 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503
#6  0x00007f5ccd7c5f65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007f5cd3967b0e in QThreadPrivate::start (arg=0x1006f50) at thread/qthread_unix.cpp:337
#8  0x00007f5cd4e876aa in start_thread (arg=0x7f5cb1b93700) at pthread_create.c:333
#9  0x00007f5cd5611eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7f5c99cc0700 (LWP 2256)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f5cd276b644 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007f5cd276b689 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007f5cd4e876aa in start_thread (arg=0x7f5c99cc0700) at pthread_create.c:333
#4  0x00007f5cd5611eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7f5cb27d8700 (LWP 24475)):
#0  0x00007f5cd5608743 in select () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f5cd3bfa101 in qt_safe_select (nfds=20, fdread=fdread@entry=0x7f5c9c019748, fdwrite=fdwrite@entry=0x7f5c9c0199d8, fdexcept=fdexcept@entry=0x7f5c9c019c68, orig_timeout=orig_timeout@entry=0x0) at kernel/qcore_unix.cpp:75
#2  0x00007f5cd3bfbcd2 in select (timeout=0x0, exceptfds=0x7f5c9c019c68, writefds=0x7f5c9c0199d8, readfds=0x7f5c9c019748, nfds=<optimized out>, this=0x7f5c9c0008c0) at kernel/qeventdispatcher_unix.cpp:320
#3  QEventDispatcherUNIXPrivate::doSelect (this=this@entry=0x7f5c9c0195b0, flags=..., flags@entry=..., timeout=timeout@entry=0x0) at kernel/qeventdispatcher_unix.cpp:196
#4  0x00007f5cd3bfc275 in QEventDispatcherUNIX::processEvents (this=0x7f5c9c0008c0, flags=...) at kernel/qeventdispatcher_unix.cpp:607
#5  0x00007f5cd3ba33e2 in QEventLoop::exec (this=this@entry=0x7f5cb27d7da0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#6  0x00007f5cd3962b44 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503
#7  0x00007f5ccd7c5f65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#8  0x00007f5cd3967b0e in QThreadPrivate::start (arg=0x22b6250) at thread/qthread_unix.cpp:337
#9  0x00007f5cd4e876aa in start_thread (arg=0x7f5cb27d8700) at pthread_create.c:333
#10 0x00007f5cd5611eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f5cd5b38800 (LWP 2222)):
[KCrash Handler]
#6  QScreen::handle (this=0x0) at kernel/qscreen.cpp:85
#7  0x00007f5cbfaba545 in QXcbWindow::QXcbWindow (this=0x1ed2d20, window=0x1f04ae0) at qxcbwindow.cpp:260
#8  0x00007f5cbfaa75c1 in QXcbIntegration::createPlatformWindow (this=<optimized out>, window=0x1f04ae0) at qxcbintegration.cpp:194
#9  0x00007f5cd3ef7786 in QWindowPrivate::create (this=0x1f066f0, recursive=recursive@entry=false) at kernel/qwindow.cpp:395
#10 0x00007f5cd3ef797b in QWindow::create (this=this@entry=0x1f04ae0) at kernel/qwindow.cpp:539
#11 0x00007f5cd3ef7b28 in QWindow::winId (this=0x1f04ae0) at kernel/qwindow.cpp:558
#12 0x00007f5cd51d4eff in KWin::AbstractThumbnailItem::findParentEffectWindow (this=0x25b1720) at ../thumbnailitem.cpp:79
#13 0x00007f5cd51d50c9 in KWin::AbstractThumbnailItem::effectWindowAdded (this=0x25b1720) at ../thumbnailitem.cpp:90
#14 0x00007f5cd526b4e5 in KWin::AbstractThumbnailItem::qt_static_metacall (_o=0x0, _c=QMetaObject::ResetProperty, _id=38598368, _a=0x7f5cd58cfc00 <main_arena>) at moc_thumbnailitem.cpp:130
#15 0x00007f5cd3bd69c9 in QMetaObject::activate (sender=0x1d0ba10, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=6, argv=argv@entry=0x7ffed7e72fd0) at kernel/qobject.cpp:3716
#16 0x00007f5cd3bd7057 in QMetaObject::activate (sender=<optimized out>, m=m@entry=0x7f5cd3394ac0 <KWin::EffectsHandler::staticMetaObject>, local_signal_index=local_signal_index@entry=6, argv=argv@entry=0x7ffed7e72fd0) at kernel/qobject.cpp:3582
#17 0x00007f5cd3186242 in KWin::EffectsHandler::windowAdded (this=<optimized out>, _t1=0x24a2fd0) at moc_kwineffects.cpp:1236
#18 0x00007f5cd3bd635a in call (a=0x7ffed7e73110, r=0x1d0ba10, this=0x19aadf0) at ../../include/QtCore/../../src/corelib/kernel/qobject_impl.h:124
#19 QMetaObject::activate (sender=sender@entry=0x1ecdab0, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=7, argv=argv@entry=0x7ffed7e73110) at kernel/qobject.cpp:3702
#20 0x00007f5cd3bd7057 in QMetaObject::activate (sender=sender@entry=0x1ecdab0, m=m@entry=0x7f5cd5505120 <KWin::Toplevel::staticMetaObject>, local_signal_index=local_signal_index@entry=7, argv=argv@entry=0x7ffed7e73110) at kernel/qobject.cpp:3582
#21 0x00007f5cd5266442 in KWin::Toplevel::windowShown (this=this@entry=0x1ecdab0, _t1=_t1@entry=0x1ecdab0) at moc_toplevel.cpp:672
#22 0x00007f5cd519c46f in KWin::Toplevel::setReadyForPainting (this=0x1ecdab0) at ../toplevel.cpp:259
#23 0x00007f5cd3bd635a in call (a=0x7ffed7e731b0, r=0x1ecdab0, this=0x199cea0) at ../../include/QtCore/../../src/corelib/kernel/qobject_impl.h:124
#24 QMetaObject::activate (sender=sender@entry=0x1d6e4f0, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3702
#25 0x00007f5cd3bd7057 in QMetaObject::activate (sender=sender@entry=0x1d6e4f0, m=m@entry=0x7f5cd3e00580 <QTimer::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3582
#26 0x00007f5cd3c56610 in QTimer::timeout (this=this@entry=0x1d6e4f0) at .moc/moc_qtimer.cpp:192
#27 0x00007f5cd3be4918 in QTimer::timerEvent (this=0x1d6e4f0, e=<optimized out>) at kernel/qtimer.cpp:247
#28 0x00007f5cd3bd76f3 in QObject::event (this=0x1d6e4f0, e=<optimized out>) at kernel/qobject.cpp:1267
#29 0x00007f5cd44afb2c in QApplicationPrivate::notify_helper (this=0xc8f8b0, receiver=0x1d6e4f0, e=0x7ffed7e73520) at kernel/qapplication.cpp:3720
#30 0x00007f5cd44b5000 in QApplication::notify (this=0x7ffed7e73760, receiver=0x1d6e4f0, e=0x7ffed7e73520) at kernel/qapplication.cpp:3503
#31 0x00007f5cd3ba5c2b in QCoreApplication::notifyInternal (this=0x7ffed7e73760, receiver=0x1d6e4f0, event=event@entry=0x7ffed7e73520) at kernel/qcoreapplication.cpp:935
#32 0x00007f5cd3bfdae5 in sendEvent (event=0x7ffed7e73520, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:228
#33 QTimerInfoList::activateTimers (this=0xd2e998) at kernel/qtimerinfo_unix.cpp:635
#34 0x00007f5cd3bfb6a0 in QEventDispatcherUNIX::activateTimers (this=this@entry=0xd2d310) at kernel/qeventdispatcher_unix.cpp:549
#35 0x00007f5cd3bfc243 in QEventDispatcherUNIX::processEvents (this=0xd2d310, flags=flags@entry=...) at kernel/qeventdispatcher_unix.cpp:611
#36 0x00007f5cbfafc96d in QUnixEventDispatcherQPA::processEvents (this=<optimized out>, flags=...) at eventdispatchers/qunixeventdispatcher.cpp:62
#37 0x00007f5cd3ba33e2 in QEventLoop::exec (this=this@entry=0x7ffed7e73680, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#38 0x00007f5cd3bab02c in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1188
#39 0x00007f5cd3eea31c in QGuiApplication::exec () at kernel/qguiapplication.cpp:1510
#40 0x00007f5cd44ab7a5 in QApplication::exec () at kernel/qapplication.cpp:2956
#41 0x00007f5cd58da310 in kdemain (argc=1, argv=0x7ffed7e738c8) at ../main_x11.cpp:300
#42 0x00007f5cd552ba40 in __libc_start_main (main=0x400790 <main(int, char**)>, argc=3, argv=0x7ffed7e738c8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffed7e738b8) at libc-start.c:289
#43 0x00000000004007c9 in _start ()

Reported using DrKonqi