SUMMARY My PC is basically a laptop with an external display. I left the screen locked for about an hour or so and then returned to my PC. Moved the mouse, screen turns on and I tried to type my password in the lockscreen which had no effect. Disconnected the external display => then typed in the password which worked => immediately reconnected the display cable => plasmashell crashed. I wasn't able to find a bug with a similar backtrace so opened this one. Core was generated by `/usr/bin/plasmashell --no-respawn'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007f172b24a8b9 in QQuickWindowPrivate::queryPointerEventInstance(QQuickPointerDevice*, QEvent::Type) const () from /usr/lib/libQt5Quick.so.5 [Current thread is 1 (Thread 0x7f17248f2f80 (LWP 135607))] (gdb) bt #0 0x00007f172b24a8b9 in QQuickWindowPrivate::queryPointerEventInstance(QQuickPointerDevice*, QEvent::Type) const () at /usr/lib/libQt5Quick.so.5 #1 0x00007f172b24acd9 in QQuickWindow::mouseGrabberItem() const () at /usr/lib/libQt5Quick.so.5 #2 0x00007f172b24e92f in QQuickWindowPrivate::removeGrabber(QQuickItem*, bool, bool) () at /usr/lib/libQt5Quick.so.5 #3 0x00007f172b2319c5 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #4 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #5 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #6 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #7 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #8 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #9 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #10 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #11 0x00007f172b2319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #12 0x00007f172b231b39 in QQuickItemPrivate::setVisible(bool) () at /usr/lib/libQt5Quick.so.5 #13 0x00007f172b23fd43 in QQuickItem::qt_metacall(QMetaObject::Call, int, void**) () at /usr/lib/libQt5Quick.so.5 #14 0x00007f172bbe09ba in PlasmaQuick::AppletQuickItem::qt_metacall(QMetaObject::Call, int, void**) () at /usr/lib/libKF5PlasmaQuick.so.5 #15 0x00007f17200b0b3a in () at /usr/lib/qt/plugins/plasma/scriptengines/plasma_appletscript_declarative.so #16 0x00007f17200bfb39 in () at /usr/lib/qt/plugins/plasma/scriptengines/plasma_appletscript_declarative.so #17 0x00007f172ac3c823 in () at /usr/lib/libQt5Qml.so.5 #18 0x00007f172ab752f2 in QV4::QObjectWrapper::setProperty(QV4::ExecutionEngine*, QObject*, QQmlPropertyData*, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #19 0x00007f172ab75876 in QV4::QObjectWrapper::setQmlProperty(QV4::ExecutionEngine*, QQmlContextData*, QObject*, QV4::String*, QV4::QObjectWrapper::RevisionMode, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #20 0x00007f172ab759d7 in QV4::QObjectWrapper::virtualPut(QV4::Managed*, QV4::PropertyKey, QV4::Value const&, QV4::Value*) () at /usr/lib/libQt5Qml.so.5 #21 0x00007f172ab23a75 in QV4::Lookup::setterFallback(QV4::Lookup*, QV4::ExecutionEngine*, QV4::Value&, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #22 0x00007f172ab8eaff in () at /usr/lib/libQt5Qml.so.5 #23 0x00007f172ab94804 in () at /usr/lib/libQt5Qml.so.5 #24 0x00007f172ab36c36 in QV4::Function::call(QV4::Value const*, QV4::Value const*, int, QV4::ExecutionContext const*) () at /usr/lib/libQt5Qml.so.5 #25 0x00007f172ac971ad in QQmlJavaScriptExpression::evaluate(QV4::CallData*, bool*) () at /usr/lib/libQt5Qml.so.5 #26 0x00007f172ac537f1 in QQmlBoundSignalExpression::evaluate(void**) () at /usr/lib/libQt5Qml.so.5 #27 0x00007f172ac5476c in () at /usr/lib/libQt5Qml.so.5 #28 0x00007f172ac7647f in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () at /usr/lib/libQt5Qml.so.5 #29 0x00007f17296be740 in () at /usr/lib/libQt5Core.so.5 #30 0x00007f172ac31fcb in QQmlVMEMetaObject::metaCall(QObject*, QMetaObject::Call, int, void**) () at /usr/lib/libQt5Qml.so.5 #31 0x00007f172969ea0c in QMetaProperty::write(QObject*, QVariant const&) const () at /usr/lib/libQt5Core.so.5 #32 0x00007f17296baf52 in QObject::setProperty(char const*, QVariant const&) () at /usr/lib/libQt5Core.so.5 #33 0x00007f172bbef1af in () at /usr/lib/libKF5PlasmaQuick.so.5 #34 0x0000556bdbb714b4 in () #35 0x00007f17296bea71 in () at /usr/lib/libQt5Core.so.5 #36 0x00007f17296c0fcf in QTimer::timeout(QTimer::QPrivateSignal) () at /usr/lib/libQt5Core.so.5 #37 0x00007f17296b1b56 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5 #38 0x00007f172a378b5c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5 #39 0x00007f172968df48 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5 #40 0x00007f17296d84b3 in QTimerInfoList::activateTimers() () at /usr/lib/libQt5Core.so.5 #41 0x00007f17296d8af2 in () at /usr/lib/libQt5Core.so.5 --Type <RET> for more, q to quit, c to continue without paging-- #42 0x00007f172843653b in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0 #43 0x00007f1728493219 in () at /usr/lib/libglib-2.0.so.0 #44 0x00007f17284351a2 in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0 #45 0x00007f17296d8c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #46 0x00007f17296866ec in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #47 0x00007f1729691219 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5 #48 0x0000556bdbb46168 in () #49 0x00007f1728e3c790 in () at /usr/lib/libc.so.6 #50 0x00007f1728e3c84a in __libc_start_main () at /usr/lib/libc.so.6 #51 0x0000556bdbb46515 in () SOFTWARE/OS VERSIONS KDE Plasma Version: 5.27.4 KDE Frameworks Version: 5.104.0 Qt Version: 5.15.8
> tried to type my password in the lockscreen which had no effect That sounds like Bug 456210. Let's use this ticket to track the crash. However the backtrace is missing debug symbols for the following stack frames that are relevant to the crash: > #15 0x00007f17200b0b3a in () at /usr/lib/qt/plugins/plasma/scriptengines/plasma_appletscript_declarative.so > #16 0x00007f17200bfb39 in () at /usr/lib/qt/plugins/plasma/scriptengines/plasma_appletscript_declarative.so Can you install debug symbols for Plasma and paste a new backtrace that has symbols for those stack frames? Thanks!
Unfortunately, even with debuginfo installed the symbols for those two are not found #0 __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=11, no_tid=no_tid@entry=0) at pthread_kill.c:44 #1 0x00007ff7c6ea0953 in __pthread_kill_internal (signo=11, threadid=<optimized out>) at pthread_kill.c:78 #2 0x00007ff7c6e51ea8 in __GI_raise (sig=11) at ../sysdeps/posix/raise.c:26 #3 0x00007ff7c976a37c in KCrash::defaultCrashHandler(int) () at /usr/lib/libKF5Crash.so.5 #4 0x00007ff7c6e51f50 in <signal handler called> () at /usr/lib/libc.so.6 #5 0x00007ff7c924a8b9 in QQuickWindowPrivate::queryPointerEventInstance(QQuickPointerDevice*, QEvent::Type) const () at /usr/lib/libQt5Quick.so.5 #6 0x00007ff7c924ad14 in QQuickWindow::mouseGrabberItem() const () at /usr/lib/libQt5Quick.so.5 #7 0x00007ff7c924e92f in QQuickWindowPrivate::removeGrabber(QQuickItem*, bool, bool) () at /usr/lib/libQt5Quick.so.5 #8 0x00007ff7c92319c5 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #9 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #10 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #11 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #12 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #13 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #14 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #15 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #16 0x00007ff7c92319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #17 0x00007ff7c9231b39 in QQuickItemPrivate::setVisible(bool) () at /usr/lib/libQt5Quick.so.5 #18 0x00007ff7c923fd43 in QQuickItem::qt_metacall(QMetaObject::Call, int, void**) () at /usr/lib/libQt5Quick.so.5 #19 0x00007ff7c9b899ba in PlasmaQuick::AppletQuickItem::qt_metacall(QMetaObject::Call, int, void**) () at /usr/lib/libKF5PlasmaQuick.so.5 #20 0x00007ff7bbfddb3a in () at /usr/lib/qt/plugins/plasma/scriptengines/plasma_appletscript_declarative.so #21 0x00007ff7bbfecb39 in () at /usr/lib/qt/plugins/plasma/scriptengines/plasma_appletscript_declarative.so #22 0x00007ff7c8c3c823 in () at /usr/lib/libQt5Qml.so.5 #23 0x00007ff7c8b752f2 in QV4::QObjectWrapper::setProperty(QV4::ExecutionEngine*, QObject*, QQmlPropertyData*, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #24 0x00007ff7c8b75876 in QV4::QObjectWrapper::setQmlProperty(QV4::ExecutionEngine*, QQmlContextData*, QObject*, QV4::String*, QV4::QObjectWrapper::RevisionMode, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #25 0x00007ff7c8b759d7 in QV4::QObjectWrapper::virtualPut(QV4::Managed*, QV4::PropertyKey, QV4::Value const&, QV4::Value*) () at /usr/lib/libQt5Qml.so.5 #26 0x00007ff7c8b23a75 in QV4::Lookup::setterFallback(QV4::Lookup*, QV4::ExecutionEngine*, QV4::Value&, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #27 0x00007ff7c8b8eaff in () at /usr/lib/libQt5Qml.so.5 #28 0x00007ff7c8b94804 in () at /usr/lib/libQt5Qml.so.5 #29 0x00007ff7c8b36c36 in QV4::Function::call(QV4::Value const*, QV4::Value const*, int, QV4::ExecutionContext const*) () at /usr/lib/libQt5Qml.so.5 #30 0x00007ff7c8c971ad in QQmlJavaScriptExpression::evaluate(QV4::CallData*, bool*) () at /usr/lib/libQt5Qml.so.5 #31 0x00007ff7c8c537f1 in QQmlBoundSignalExpression::evaluate(void**) () at /usr/lib/libQt5Qml.so.5 #32 0x00007ff7c8c5476c in () at /usr/lib/libQt5Qml.so.5 #33 0x00007ff7c8c7647f in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () at /usr/lib/libQt5Qml.so.5 #34 0x00007ff7c76be740 in () at /usr/lib/libQt5Core.so.5 #35 0x00007ff7c8c31fcb in QQmlVMEMetaObject::metaCall(QObject*, QMetaObject::Call, int, void**) () at /usr/lib/libQt5Qml.so.5 #36 0x00007ff7c769ea0c in QMetaProperty::write(QObject*, QVariant const&) const () at /usr/lib/libQt5Core.so.5 #37 0x00007ff7c76baf52 in QObject::setProperty(char const*, QVariant const&) () at /usr/lib/libQt5Core.so.5 #38 0x00007ff7c9b981af in () at /usr/lib/libKF5PlasmaQuick.so.5 #39 0x0000557a0c0814b4 in ShellCorona::createWaitingPanels() (this=<optimized out>) at /usr/src/debug/plasma-workspace/plasma-workspace-5.27.4.1/shell/shellcorona.cpp:1488 #40 0x00007ff7c76bea71 in () at /usr/lib/libQt5Core.so.5 #41 0x00007ff7c76c0fcf in QTimer::timeout(QTimer::QPrivateSignal) () at /usr/lib/libQt5Core.so.5 --Type <RET> for more, q to quit, c to continue without paging-- #42 0x00007ff7c76b1b56 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5 #43 0x00007ff7c8378b5c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5 #44 0x00007ff7c768df48 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5 #45 0x00007ff7c76d84b3 in QTimerInfoList::activateTimers() () at /usr/lib/libQt5Core.so.5 #46 0x00007ff7c76d8af2 in () at /usr/lib/libQt5Core.so.5 #47 0x00007ff7c63db53b in g_main_dispatch (context=0x7ff7bc000ee0) at ../glib/glib/gmain.c:3460 #48 g_main_context_dispatch (context=0x7ff7bc000ee0) at ../glib/glib/gmain.c:4200 #49 0x00007ff7c6438219 in g_main_context_iterate.constprop.0 (context=0x7ff7bc000ee0, block=1, dispatch=1, self=<optimized out>) at ../glib/glib/gmain.c:4276 #50 0x00007ff7c63da1a2 in g_main_context_iteration (context=0x7ff7bc000ee0, may_block=1) at ../glib/glib/gmain.c:4343 #51 0x00007ff7c76d8c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #52 0x00007ff7c76866ec in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #53 0x00007ff7c7691219 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5 #54 0x0000557a0c056168 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/plasma-workspace/plasma-workspace-5.27.4.1/shell/main.cpp:235
Are you by any chance using any 3rd-party KWin scripts? I also see we were in ShellCorona::createWaitingPanels() like in Bug 443708, but the part of the backtrace until then isn't the same.
Not really. I have 4 kwin scripts in the settings: - Desktop Change OSD - Minimize All - Syncronize Skip Switcher with Taskbar - Video Wall I have one addon in the plasma task bottom panel: Todolist The crash happened twice today and not on login but just reconnecting the display. I haven't restarted my computer since the first crash and after the crash I started plasma manually so have the debug output which I am attaching to the ticket
Created attachment 158486 [details] Debug output There are quite a few warnings that should ideally not be there. Some look worrisome especially the ones with "binding loop detected" and... QFont::setPointSizeF: Point size <= 0 (0.000000), must be greater than 0 QObject::connect: No such slot DesktopProtocol::_k_slotRedirection(KIO::Job *, QUrl) file:///usr/share/plasma/plasmoids/org.kde.kscreen/contents/ui/main.qml:30:5: Unable to assign [undefined] to bool file:///usr/share/plasma/plasmoids/org.kde.plasma.networkmanagement/contents/ui/main.qml:95: TypeError: Cannot read property 'airplaneModeAvailable' of null file:///usr/share/plasma/plasmoids/org.kde.plasma.kicker/contents/ui/ItemListView.qml:33: TypeError: Value is null and could not be converted to an object kf.coreaddons: Expected a KPluginFactory, got a KIOPluginForMetaData file:///usr/share/plasma/plasmoids/org.kde.plasma.kicker/contents/ui/RunnerResultsList.qml:50:9: Unable to assign [undefined] to int
I think ultimately we need to get debug symbols for plasma_appletscript_declarative.so to make progress on this.
Here you go: #0 0x00007ff739e4a8b9 in QQuickWindowPrivate::queryPointerEventInstance(QQuickPointerDevice*, QEvent::Type) const () at /usr/lib/libQt5Quick.so.5 #1 0x00007ff739e4acd9 in QQuickWindow::mouseGrabberItem() const () at /usr/lib/libQt5Quick.so.5 #2 0x00007ff739e4e92f in QQuickWindowPrivate::removeGrabber(QQuickItem*, bool, bool) () at /usr/lib/libQt5Quick.so.5 #3 0x00007ff739e319c5 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #4 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #5 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #6 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #7 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #8 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #9 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #10 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #11 0x00007ff739e319f8 in QQuickItemPrivate::setEffectiveVisibleRecur(bool) () at /usr/lib/libQt5Quick.so.5 #12 0x00007ff739e31b39 in QQuickItemPrivate::setVisible(bool) () at /usr/lib/libQt5Quick.so.5 #13 0x00007ff739e3fd43 in QQuickItem::qt_metacall(QMetaObject::Call, int, void**) () at /usr/lib/libQt5Quick.so.5 #14 0x00007ff73ade4fcd in PlasmaQuick::AppletQuickItem::qt_metacall(QMetaObject::Call, int, void**) (this=0x56429ff82530, _c=QMetaObject::WriteProperty, _id=12, _a=0x7ffd97cf9050) at KF5PlasmaQuick_autogen/include/moc_appletquickitem.cpp:364 #15 0x00007ff72bfb98fd in AppletInterface::qt_metacall(QMetaObject::Call, int, void**) (this=0x56429ff82530, _c=QMetaObject::WriteProperty, _id=12, _a=0x7ffd97cf9050) at plasma_appletscript_declarative_autogen/include/moc_appletinterface.cpp:887 #16 0x00007ff72bfd12cd in ContainmentInterface::qt_metacall(QMetaObject::Call, int, void**) (this=0x56429ff82530, _c=QMetaObject::WriteProperty, _id=12, _a=0x7ffd97cf9050) at plasma_appletscript_declarative_autogen/include/moc_containmentinterface.cpp:459 #17 0x00007ff73983c823 in () at /usr/lib/libQt5Qml.so.5 #18 0x00007ff7397752f2 in QV4::QObjectWrapper::setProperty(QV4::ExecutionEngine*, QObject*, QQmlPropertyData*, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #19 0x00007ff739775876 in QV4::QObjectWrapper::setQmlProperty(QV4::ExecutionEngine*, QQmlContextData*, QObject*, QV4::String*, QV4::QObjectWrapper::RevisionMode, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #20 0x00007ff7397759d7 in QV4::QObjectWrapper::virtualPut(QV4::Managed*, QV4::PropertyKey, QV4::Value const&, QV4::Value*) () at /usr/lib/libQt5Qml.so.5 #21 0x00007ff739723a75 in QV4::Lookup::setterFallback(QV4::Lookup*, QV4::ExecutionEngine*, QV4::Value&, QV4::Value const&) () at /usr/lib/libQt5Qml.so.5 #22 0x00007ff73978eaff in () at /usr/lib/libQt5Qml.so.5 #23 0x00007ff739794804 in () at /usr/lib/libQt5Qml.so.5 #24 0x00007ff739736c36 in QV4::Function::call(QV4::Value const*, QV4::Value const*, int, QV4::ExecutionContext const*) () at /usr/lib/libQt5Qml.so.5 #25 0x00007ff7398971ad in QQmlJavaScriptExpression::evaluate(QV4::CallData*, bool*) () at /usr/lib/libQt5Qml.so.5 #26 0x00007ff7398537f1 in QQmlBoundSignalExpression::evaluate(void**) () at /usr/lib/libQt5Qml.so.5 #27 0x00007ff73985476c in () at /usr/lib/libQt5Qml.so.5 #28 0x00007ff73987647f in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () at /usr/lib/libQt5Qml.so.5 #29 0x00007ff737abe740 in () at /usr/lib/libQt5Core.so.5 #30 0x00007ff739831fcb in QQmlVMEMetaObject::metaCall(QObject*, QMetaObject::Call, int, void**) () at /usr/lib/libQt5Qml.so.5 #31 0x00007ff737a9ea0c in QMetaProperty::write(QObject*, QVariant const&) const () at /usr/lib/libQt5Core.so.5 #32 0x00007ff737abaf52 in QObject::setProperty(char const*, QVariant const&) () at /usr/lib/libQt5Core.so.5 #33 0x00007ff73ae025b8 in PlasmaQuick::ContainmentViewPrivate::setContainment(Plasma::Containment*) (this=0x5642a0968bd0, cont=0x56429ff74c70) at /home/waqar/kde/src/frameworks/plasma-framework/src/plasmaquick/containmentview.cpp:124 #34 0x00007ff73ae03361 in PlasmaQuick::ContainmentView::setContainment(Plasma::Containment*) (this=0x5642a0f9e500, cont=0x56429ff74c70) at /home/waqar/kde/src/frameworks/plasma-framework/src/plasmaquick/containmentview.cpp:251 #35 0x000056429f2d337a in ShellCorona::createWaitingPanels() (this=0x56429f958880) at /home/waqar/kde/src/plasma/plasma-workspace/shell/shellcorona.cpp:1488 #36 0x000056429f2f93d8 in QtPrivate::FunctorCall<QtPrivate::IndexesList<>, QtPrivate::List<>, void, void (ShellCorona::*)()>::call(void (ShellCorona::*)(), ShellCorona*, void**) (f=(void (ShellCorona::*)(ShellCorona * const)) 0x56429f2d2f40 <ShellCorona::createWaitingPanels()>, o=0x56429f958880, arg=0x7ffd97cfbae0) at /usr/include/qt/QtCore/qobjectdefs_impl.h:152 #37 0x000056429f2f933d in QtPrivate::FunctionPointer<void (ShellCorona::*)()>::call<QtPrivate::List<>, void>(void (ShellCorona::*)(), ShellCorona*, void**) (f=(void (ShellCorona::*)(ShellCorona * const)) 0x56429f2d2f40 <ShellCorona::createWaitingPanels()>, o=0x56429f958880, arg=0x7ffd97cfbae0) at /usr/include/qt/QtCore/qobjectdefs_impl.h:185 --Type <RET> for more, q to quit, c to continue without paging-- #38 0x000056429f2f9282 in QtPrivate::QSlotObject<void (ShellCorona::*)(), QtPrivate::List<>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (which=1, this_=0x56429f981560, r=0x56429f958880, a=0x7ffd97cfbae0, ret=0x0) at /usr/include/qt/QtCore/qobjectdefs_impl.h:418 #39 0x00007ff737abea71 in () at /usr/lib/libQt5Core.so.5 #40 0x00007ff737ac0fcf in QTimer::timeout(QTimer::QPrivateSignal) () at /usr/lib/libQt5Core.so.5 #41 0x00007ff737ab1b56 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5 #42 0x00007ff738978b5c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5 #43 0x00007ff737a8df48 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5 #44 0x00007ff737ad84b3 in QTimerInfoList::activateTimers() () at /usr/lib/libQt5Core.so.5 #45 0x00007ff737ad8af2 in () at /usr/lib/libQt5Core.so.5 #46 0x00007ff736ada53b in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0 #47 0x00007ff736b37219 in () at /usr/lib/libglib-2.0.so.0 #48 0x00007ff736ad91a2 in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0 #49 0x00007ff737ad8c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #50 0x00007ff737a866ec in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #51 0x00007ff737a91219 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5 #52 0x000056429f29febc in main(int, char**) (argc=2, argv=0x7ffd97cfc7e8) at /home/waqar/kde/src/plasma/plasma-workspace/shell/main.cpp:236 This is latest kf5/plasma-5.27 I reproduce by just plugging/unplugging the external display.
Aha, it's Bug 449981. Will re-open it. *** This bug has been marked as a duplicate of bug 449981 ***