Application: kcmshell5 (5.2.2)

Qt Version: 5.4.1
Operating System: Linux 3.19.0-15-generic x86_64
Distribution: Ubuntu 15.04

-- Information about the crash:
- What I was doing when the application crashed:
I had just adjusted the display configuration, specificially I had changed the resolution of my second monitor to 1920x1080.

This worked, but I immediately noticed some screen lag / jankiness.

Suddenly, the lag went away and the Error Alert Dialog appeared, telling me KDE control module crashed.

-- Backtrace:
Application: KDE Control Module (kcmshell5), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f38056b0800 (LWP 1651))]

Thread 2 (Thread 0x7f37ef145700 (LWP 1652)):
#0  0x00007f380518f8dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f37fd87bb72 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f37fd87d64f in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f37f18b1099 in QXcbEventReader::run (this=0x26700f0) at qxcbconnection.cpp:1105
#4  0x00007f3803212b0e in QThreadPrivate::start (arg=0x26700f0) at thread/qthread_unix.cpp:337
#5  0x00007f3802c496aa in start_thread (arg=0x7f37ef145700) at pthread_create.c:333
#6  0x00007f380519aeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f38056b0800 (LWP 1651)):
[KCrash Handler]
#6  0x00007f3802129de4 in QQuickWindow::maybeUpdate() () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007f3802115e28 in QQuickItemPrivate::dirty(QQuickItemPrivate::DirtyType) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#8  0x00007f3802120045 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#9  0x00007f380348273a in QObject::event (this=0x2c712a0, e=<optimized out>) at kernel/qobject.cpp:1245
#10 0x00007f380211eb6b in QQuickItem::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#11 0x00007f380380db2c in QApplicationPrivate::notify_helper (this=0x2646080, receiver=0x2c712a0, e=0x7f37d44ff0a0) at kernel/qapplication.cpp:3720
#12 0x00007f3803813000 in QApplication::notify (this=0x7fff224590d0, receiver=0x2c712a0, e=0x7f37d44ff0a0) at kernel/qapplication.cpp:3503
#13 0x00007f3803450c2b in QCoreApplication::notifyInternal (this=0x7fff224590d0, receiver=0x2c712a0, event=event@entry=0x7f37d44ff0a0) at kernel/qcoreapplication.cpp:935
#14 0x00007f3803452c9b in sendEvent (event=0x7f37d44ff0a0, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:228
#15 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x263e180) at kernel/qcoreapplication.cpp:1552
#16 0x00007f3803453298 in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1410
#17 0x00007f38034a9843 in postEventSourceDispatch (s=0x2698790) at kernel/qeventdispatcher_glib.cpp:271
#18 0x00007f37fd157c3d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007f37fd157f20 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007f37fd157fcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007f38034a9c57 in QEventDispatcherGlib::processEvents (this=0x269d910, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#22 0x00007f380344e3e2 in QEventLoop::exec (this=this@entry=0x7fff22457e50, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#23 0x00007f37ed10c01e in KScreen::ConfigOperation::exec (this=0x2d3d110) at ../../src/configoperation.cpp:107
#24 0x00007f37ed33f33c in KCMKScreen::save (this=0x2aa0ae0) at ../../../kcm/src/kcm_kscreen.cpp:144
#25 0x00007f3804e73077 in KCModuleProxy::save (this=this@entry=0x2745950) at ../../src/kcmoduleproxy.cpp:272
#26 0x00007f3804e702f0 in KCMultiDialogPrivate::apply (this=<optimized out>) at ../../src/kcmultidialog.cpp:323
#27 0x00007f3804e70695 in KCMultiDialog::qt_static_metacall (_o=0x2aa0ae0, _c=46600864, _id=865, _a=0x7f37d43f48a0) at ./moc_kcmultidialog.cpp:112
#28 0x00007f38034819c9 in QMetaObject::activate (sender=sender@entry=0x2788ee0, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=2, argv=argv@entry=0x7fff224582e0) at kernel/qobject.cpp:3716
#29 0x00007f3803482057 in QMetaObject::activate (sender=sender@entry=0x2788ee0, m=m@entry=0x7f3803d47a60 <QAbstractButton::staticMetaObject>, local_signal_index=local_signal_index@entry=2, argv=argv@entry=0x7fff224582e0) at kernel/qobject.cpp:3582
#30 0x00007f3803bbc012 in QAbstractButton::clicked (this=this@entry=0x2788ee0, _t1=false) at .moc/moc_qabstractbutton.cpp:298
#31 0x00007f3803909675 in QAbstractButtonPrivate::emitClicked (this=0x2789430) at widgets/qabstractbutton.cpp:534
#32 0x00007f380390a299 in QAbstractButtonPrivate::click (this=0x2789430) at widgets/qabstractbutton.cpp:527
#33 0x00007f380390a454 in QAbstractButton::mouseReleaseEvent (this=0x2788ee0, e=0x7fff224587a0) at widgets/qabstractbutton.cpp:1132
#34 0x00007f38038511e8 in QWidget::event (this=0x2788ee0, event=0x7fff224587a0) at kernel/qwidget.cpp:9022
#35 0x00007f380380db2c in QApplicationPrivate::notify_helper (this=0x2646080, receiver=0x2788ee0, e=0x7fff224587a0) at kernel/qapplication.cpp:3720
#36 0x00007f38038138eb in QApplication::notify (this=0x7fff224584e0, receiver=0x7fff22458500, e=0x7fff224587a0) at kernel/qapplication.cpp:3280
#37 0x00007f3803450c2b in QCoreApplication::notifyInternal (this=0x7fff224590d0, receiver=receiver@entry=0x2788ee0, event=event@entry=0x7fff224587a0) at kernel/qcoreapplication.cpp:935
#38 0x00007f38038123da in sendSpontaneousEvent (event=0x7fff224587a0, receiver=0x2788ee0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#39 QApplicationPrivate::sendMouseEvent (receiver=0x2788ee0, event=0x7fff224587a0, alienWidget=0x2788ee0, nativeWidget=0x274c970, buttonDown=<optimized out>, lastMouseReceiver=..., spontaneous=true) at kernel/qapplication.cpp:2751
#40 0x00007f3803869cc0 in QWidgetWindow::handleMouseEvent (this=0x28556b0, event=0x7fff22458bb0) at kernel/qwidgetwindow.cpp:543
#41 0x00007f380386be33 in QWidgetWindow::event (this=0x28556b0, event=0x7fff22458bb0) at kernel/qwidgetwindow.cpp:210
#42 0x00007f380380db2c in QApplicationPrivate::notify_helper (this=0x2646080, receiver=0x28556b0, e=0x7fff22458bb0) at kernel/qapplication.cpp:3720
#43 0x00007f3803813000 in QApplication::notify (this=0x7fff224590d0, receiver=0x28556b0, e=0x7fff22458bb0) at kernel/qapplication.cpp:3503
#44 0x00007f3803450c2b in QCoreApplication::notifyInternal (this=0x7fff224590d0, receiver=0x28556b0, event=0x7fff22458bb0) at kernel/qcoreapplication.cpp:935
#45 0x00007f3800d2ff82 in sendSpontaneousEvent (event=<optimized out>, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#46 QGuiApplicationPrivate::processMouseEvent (e=0x27fc8c0) at kernel/qguiapplication.cpp:1774
#47 0x00007f3800d31b45 in QGuiApplicationPrivate::processWindowSystemEvent (e=e@entry=0x27fc8c0) at kernel/qguiapplication.cpp:1576
#48 0x00007f3800d1634f in QWindowSystemInterface::sendWindowSystemEvents (flags=...) at kernel/qwindowsysteminterface.cpp:572
#49 0x00007f37f18db590 in userEventSourceDispatch (source=<optimized out>) at eventdispatchers/qeventdispatcher_glib.cpp:70
#50 0x00007f37fd157c3d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#51 0x00007f37fd157f20 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#52 0x00007f37fd157fcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#53 0x00007f38034a9c57 in QEventDispatcherGlib::processEvents (this=0x269d910, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#54 0x00007f380344e3e2 in QEventLoop::exec (this=this@entry=0x7fff22458f60, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#55 0x00007f3803a0f4b5 in QDialog::exec (this=0x274c970) at dialogs/qdialog.cpp:541
#56 0x00007f38054669cb in kdemain (_argc=<optimized out>, _argv=<optimized out>) at ../../kcmshell/main.cpp:307
#57 0x00007f38050b4a40 in __libc_start_main (main=0x400730 <main(int, char**)>, argc=2, argv=0x7fff22459218, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff22459208) at libc-start.c:289
#58 0x0000000000400769 in _start ()

Reported using DrKonqi