Application: kwin_x11 (5.2.2)

Qt Version: 5.4.1
Operating System: Linux 3.19.0-16-generic x86_64
Distribution: Ubuntu 15.04

-- Information about the crash:
- What I was doing when the application crashed:
* Recently upgraded to Ubuntu 15
* Open laptop lid
* External monitor is plugged in, but video only shows on laptop
* Ran kcm_kscreen
* Video goes to external monitor and kwin crashes

-- 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 0x7f09640cb800 (LWP 25920))]

Thread 3 (Thread 0x7f0946dba700 (LWP 25949)):
#0  0x00007f0963ba5743 in select () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f09623ef101 in qt_safe_select (nfds=16, fdread=fdread@entry=0x7f093c000a78, fdwrite=fdwrite@entry=0x7f093c000d08, fdexcept=fdexcept@entry=0x7f093c000f98, orig_timeout=orig_timeout@entry=0x0) at kernel/qcore_unix.cpp:75
#2  0x00007f09623f0cd2 in select (timeout=0x0, exceptfds=0x7f093c000f98, writefds=0x7f093c000d08, readfds=0x7f093c000a78, nfds=<optimized out>, this=0x7f093c0008c0) at kernel/qeventdispatcher_unix.cpp:320
#3  QEventDispatcherUNIXPrivate::doSelect (this=this@entry=0x7f093c0008e0, flags=..., flags@entry=..., timeout=timeout@entry=0x0) at kernel/qeventdispatcher_unix.cpp:196
#4  0x00007f09623f1275 in QEventDispatcherUNIX::processEvents (this=0x7f093c0008c0, flags=...) at kernel/qeventdispatcher_unix.cpp:607
#5  0x00007f09623983e2 in QEventLoop::exec (this=this@entry=0x7f0946db9da0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#6  0x00007f0962157b44 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503
#7  0x00007f095c00af65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#8  0x00007f096215cb0e in QThreadPrivate::start (arg=0xcb8310) at thread/qthread_unix.cpp:337
#9  0x00007f095b1d76aa in start_thread (arg=0x7f0946dba700) at pthread_create.c:333
#10 0x00007f0963baeeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7f0936485700 (LWP 25970)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f0960f61644 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007f0960f61689 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007f095b1d76aa in start_thread (arg=0x7f0936485700) at pthread_create.c:333
#4  0x00007f0963baeeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f09640cb800 (LWP 25920)):
[KCrash Handler]
#6  QScreen::handle (this=0x0) at kernel/qscreen.cpp:85
#7  0x00007f094ef86545 in QXcbWindow::QXcbWindow (this=0x1ab4ad0, window=0x25a9080) at qxcbwindow.cpp:260
#8  0x00007f094ef735c1 in QXcbIntegration::createPlatformWindow (this=<optimized out>, window=0x25a9080) at qxcbintegration.cpp:194
#9  0x00007f09626ec786 in QWindowPrivate::create (this=0x25a9530, recursive=recursive@entry=false) at kernel/qwindow.cpp:395
#10 0x00007f09626ec97b in QWindow::create (this=this@entry=0x25a9080) at kernel/qwindow.cpp:539
#11 0x00007f09626ecb28 in QWindow::winId (this=0x25a9080) at kernel/qwindow.cpp:558
#12 0x00007f0963788c9f in KWin::AbstractThumbnailItem::findParentEffectWindow (this=0x2702b80) at ../thumbnailitem.cpp:79
#13 0x00007f0963788e69 in KWin::AbstractThumbnailItem::effectWindowAdded (this=0x2702b80) at ../thumbnailitem.cpp:90
#14 0x00007f0963813125 in KWin::AbstractThumbnailItem::qt_static_metacall (_o=0x0, _c=QMetaObject::ResetProperty, _id=28506928, _a=0x7f0963e6cc00 <main_arena>) at moc_thumbnailitem.cpp:130
#15 0x00007f09623cb9c9 in QMetaObject::activate (sender=0x19b8500, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=5, argv=argv@entry=0x7ffe32f367d0) at kernel/qobject.cpp:3716
#16 0x00007f09623cc057 in QMetaObject::activate (sender=<optimized out>, m=m@entry=0x7f0961b89ac0 <KWin::EffectsHandler::staticMetaObject>, local_signal_index=local_signal_index@entry=5, argv=argv@entry=0x7ffe32f367d0) at kernel/qobject.cpp:3582
#17 0x00007f096197afb2 in KWin::EffectsHandler::windowAdded (this=<optimized out>, _t1=0xb4c4a0) at moc_kwineffects.cpp:1195
#18 0x00007f09623cb35a in call (a=0x7ffe32f36910, r=0x19b8500, this=0x2a5ca00) at ../../include/QtCore/../../src/corelib/kernel/qobject_impl.h:124
#19 QMetaObject::activate (sender=sender@entry=0x1abc3c0, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=7, argv=argv@entry=0x7ffe32f36910) at kernel/qobject.cpp:3702
#20 0x00007f09623cc057 in QMetaObject::activate (sender=sender@entry=0x1abc3c0, m=m@entry=0x7f0963a9c2e0 <KWin::Toplevel::staticMetaObject>, local_signal_index=local_signal_index@entry=7, argv=argv@entry=0x7ffe32f36910) at kernel/qobject.cpp:3582
#21 0x00007f096380dfc2 in KWin::Toplevel::windowShown (this=this@entry=0x1abc3c0, _t1=_t1@entry=0x1abc3c0) at moc_toplevel.cpp:656
#22 0x00007f0963754ddf in KWin::Toplevel::setReadyForPainting (this=this@entry=0x1abc3c0) at ../toplevel.cpp:245
#23 0x00007f096370732f in KWin::Client::syncEvent (this=0x1abc3c0, e=<optimized out>) at ../events.cpp:1561
#24 0x00007f096370a301 in KWin::Workspace::workspaceEvent (this=0xb66150, e=0x7f09480056d0) at ../events.cpp:556
#25 0x00007f0962397510 in QAbstractEventDispatcher::filterNativeEvent (this=this@entry=0xb35630, eventType=..., message=message@entry=0x7f09480056d0, result=result@entry=0x7ffe32f36aa8) at kernel/qabstracteventdispatcher.cpp:460
#26 0x00007f094ef7102d in QXcbConnection::handleXcbEvent (this=this@entry=0xb04760, event=event@entry=0x7f09480056d0) at qxcbconnection.cpp:863
#27 0x00007f094ef724bb in QXcbConnection::processXcbEvents (this=0xb04760) at qxcbconnection.cpp:1303
#28 0x00007f09623cc73a in QObject::event (this=0xb04760, e=<optimized out>) at kernel/qobject.cpp:1245
#29 0x00007f0962ca4b2c in QApplicationPrivate::notify_helper (this=0xafda80, receiver=0xb04760, e=0x7f0948006740) at kernel/qapplication.cpp:3720
#30 0x00007f0962caa000 in QApplication::notify (this=0x7ffe32f37190, receiver=0xb04760, e=0x7f0948006740) at kernel/qapplication.cpp:3503
#31 0x00007f096239ac2b in QCoreApplication::notifyInternal (this=0x7ffe32f37190, receiver=0xb04760, event=event@entry=0x7f0948006740) at kernel/qcoreapplication.cpp:935
#32 0x00007f096239cc9b in sendEvent (event=0x7f0948006740, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:228
#33 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0xaee2f0) at kernel/qcoreapplication.cpp:1552
#34 0x00007f09623f1112 in QEventDispatcherUNIX::processEvents (this=0xb35630, flags=flags@entry=...) at kernel/qeventdispatcher_unix.cpp:579
#35 0x00007f094efc896d in QUnixEventDispatcherQPA::processEvents (this=<optimized out>, flags=...) at eventdispatchers/qunixeventdispatcher.cpp:62
#36 0x00007f09623983e2 in QEventLoop::exec (this=this@entry=0x7ffe32f370b0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#37 0x00007f09623a002c in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1188
#38 0x00007f09626df31c in QGuiApplication::exec () at kernel/qguiapplication.cpp:1510
#39 0x00007f0962ca07a5 in QApplication::exec () at kernel/qapplication.cpp:2956
#40 0x00007f0963e768c3 in kdemain (argc=1, argv=0x7ffe32f372e8) at ../main_x11.cpp:294
#41 0x00007f0963ac8a40 in __libc_start_main (main=0x400790 <main(int, char**)>, argc=1, argv=0x7ffe32f372e8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe32f372d8) at libc-start.c:289
#42 0x00000000004007c9 in _start ()

Reported using DrKonqi