Application: kwin_x11 (5.3.2) Qt Version: 5.5.0 Operating System: Linux 4.1.4-1-ARCH x86_64 Distribution (Platform): Archlinux Packages -- Information about the crash: locked screen, pressed a key to get to the unlock screen -> error The crash can be reproduced sometimes. -- Backtrace: Application: KWin (kwin_x11), signal: Segmentation fault Using host libthread_db library "/usr/lib/libthread_db.so.1". [Current thread is 1 (Thread 0x7f12a2bfb840 (LWP 27135))] Thread 3 (Thread 0x7f1281cee700 (LWP 27151)): #0 0x00007f12a2629e23 in select () from /usr/lib/libc.so.6 #1 0x00007f12a03e491f in qt_safe_select(int, fd_set*, fd_set*, fd_set*, timespec const*) () from /usr/lib/libQt5Core.so.5 #2 0x00007f12a03e63f7 in QEventDispatcherUNIXPrivate::doSelect(QFlags<QEventLoop::ProcessEventsFlag>, timespec*) () from /usr/lib/libQt5Core.so.5 #3 0x00007f12a03e68fe in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5 #4 0x00007f12a039026a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5 #5 0x00007f12a01acaf4 in QThread::exec() () from /usr/lib/libQt5Core.so.5 #6 0x00007f129a6f0345 in ?? () from /usr/lib/libQt5Qml.so.5 #7 0x00007f12a01b1a9e in ?? () from /usr/lib/libQt5Core.so.5 #8 0x00007f12a1e9f4a4 in start_thread () from /usr/lib/libpthread.so.0 #9 0x00007f12a263112d in clone () from /usr/lib/libc.so.6 Thread 2 (Thread 0x7f127aef2700 (LWP 27161)): #0 0x00007f12a1ea507f in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0 #1 0x00007f129f108564 in ?? () from /usr/lib/libQt5Script.so.5 #2 0x00007f129f1085a9 in ?? () from /usr/lib/libQt5Script.so.5 #3 0x00007f12a1e9f4a4 in start_thread () from /usr/lib/libpthread.so.0 #4 0x00007f12a263112d in clone () from /usr/lib/libc.so.6 Thread 1 (Thread 0x7f12a2bfb840 (LWP 27135)): [KCrash Handler] #5 0x00007f1289c9847e in QXcbScreen::mapToNative(QRect const&) const () from /usr/lib/libQt5XcbQpa.so.5 #6 0x00007f1289c9d683 in QXcbWindow::mapToNative(QRect const&, QXcbScreen const*) const () from /usr/lib/libQt5XcbQpa.so.5 #7 0x00007f1289c9ee7b in QXcbWindow::propagateSizeHints() () from /usr/lib/libQt5XcbQpa.so.5 #8 0x00007f1289ca3cec in QXcbWindow::setGeometry(QRect const&) () from /usr/lib/libQt5XcbQpa.so.5 #9 0x00007f12a08f7bfc in QWindow::setX(int) () from /usr/lib/libQt5Gui.so.5 #10 0x00007f12a08fa548 in ?? () from /usr/lib/libQt5Gui.so.5 #11 0x00007f12a08fafbb in QWindow::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libQt5Gui.so.5 #12 0x00007f129abf5025 in QQuickWindow::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libQt5Quick.so.5 #13 0x00007f11ed2d49b5 in PlasmaQuick::Dialog::qt_metacall (this=0x1eca360, _c=QMetaObject::WriteProperty, _id=<optimized out>, _a=0x7ffc31d8bed0) at /home/fwolfsjaeger/debug/extra/plasma-framework/src/build/src/plasmaquick/moc_dialog.cpp:374 #14 0x00007f129a66e69d in QQmlPropertyPrivate::writeBinding(QObject*, QQmlPropertyData const&, QQmlContextData*, QQmlJavaScriptExpression*, QV4::Value const&, bool, QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/libQt5Qml.so.5 #15 0x00007f129a6dc86f in QQmlBinding::update(QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/libQt5Qml.so.5 #16 0x00007f129a6dcc9e in QQmlBinding::expressionChanged(QQmlJavaScriptExpression*) () from /usr/lib/libQt5Qml.so.5 #17 0x00007f129a6b8c77 in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () from /usr/lib/libQt5Qml.so.5 #18 0x00007f129a6b8c3e in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () from /usr/lib/libQt5Qml.so.5 #19 0x00007f129a6b8c3e in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () from /usr/lib/libQt5Qml.so.5 #20 0x00007f129a65b8bc in QQmlData::signalEmitted(QAbstractDeclarativeData*, QObject*, int, void**) () from /usr/lib/libQt5Qml.so.5 #21 0x00007f12a03c08f0 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQt5Core.so.5 #22 0x00007f12a03c0e77 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQt5Core.so.5 #23 0x00007f12a22a71f3 in ?? () from /usr/lib/libkwin.so.5 #24 0x00007f12a03c0fea in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQt5Core.so.5 #25 0x00007f12a03cdf38 in QTimer::timerEvent(QTimerEvent*) () from /usr/lib/libQt5Core.so.5 #26 0x00007f12a03c1e63 in QObject::event(QEvent*) () from /usr/lib/libQt5Core.so.5 #27 0x00007f12a10cc00c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5 #28 0x00007f12a10d14e6 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5 #29 0x00007f12a039289b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5 #30 0x00007f12a03e805d in QTimerInfoList::activateTimers() () from /usr/lib/libQt5Core.so.5 #31 0x00007f12a03e6876 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5 #32 0x00007f1289cee01d in ?? () from /usr/lib/libQt5XcbQpa.so.5 #33 0x00007f12a039026a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5 #34 0x00007f12a039820c in QCoreApplication::exec() () from /usr/lib/libQt5Core.so.5 #35 0x00007f12a28f15ef in kdemain () from /usr/lib/libkdeinit5_kwin_x11.so #36 0x00007f12a2568610 in __libc_start_main () from /usr/lib/libc.so.6 #37 0x00000000004007b9 in _start () Reported using DrKonqi
I'm sorry but this backtrace lacks debug symbols, so it's impossible to say where and why it crashed, which is a requirement for fixing it.
It's not so easy to get debug symbols in Arch, I had to recompile some packages to get at least that much. Almost every time when I'd like to get to the unlock screen (SDDM) kdeinit5 (package kinit) crashes, which can then only be resolved by killing the SDDM process. Sometimes some other processes, like plasma, crash as well. It's really annoying, if you can tell me how to get some proper debug information, I'd gladly provide you with those ;)
I bet everyones every arms that the QXcbScreen is 0x0. run "kcmshell5 kded" and stop & disable the kscreen daemon. In case this is because your display turns off and kscreen unregisters it, that should prevent the crashes.
Thanks for the tip, the kscreen daemon's deactivated now, I'll let you know if this "solves" my problem.
(In reply to Thomas Lübking from comment #3) > I bet everyones every arms that the QXcbScreen is 0x0. > > run "kcmshell5 kded" and stop & disable the kscreen daemon. In case this is > because your display turns off and kscreen unregisters it, that should > prevent the crashes. Thanks a lot, my problem's solved, it no longer crashes and I get to the lock screen! I do have some other issues though were I weren't able to add debug symbols yet. It's about some screen flickering, issues with the plasma 5 taskbar, etc. Since I don't have any useful debug output I can't create a proper error message though, so may I contact anyone directly to get some hints on how to figure those out?
Screen flicker may have various causes. Relevant information are - only with enabled compositor? - limited to some area (thr taskbar) or across the entire screen - used graphics hardware/drivers and in case of "compositing only issue", the output of qdbus org.kde.KWin /KWin supportInformation *** This bug has been marked as a duplicate of bug 341497 ***
Created attachment 94037 [details] qdbus org.kde.KWin /KWin supportInformation
Created attachment 94038 [details] lshw -c video
Created attachment 94039 [details] modinfo i915
(In reply to Thomas Lübking from comment #6) > Screen flicker may have various causes. > > Relevant information are > - only with enabled compositor? > - limited to some area (thr taskbar) or across the entire screen > - used graphics hardware/drivers and in case of "compositing only issue", > the output of > qdbus org.kde.KWin /KWin supportInformation > > *** This bug has been marked as a duplicate of bug 341497 *** It's hard to describe, some of the shell output that's printed before the display manager is started is shimmering / flickering through. It's only visible on dark backgrounds and happens on 2 areas across the entire screens. Though sometimes isn't there at all, I haven't figured out the cause yet. I can try starting with the compositor disabled, if I disable it afterwards using Alt+Shift+F12 it has no effect. Graphics hardware/info and qdbus /KWin supportInformation is attached ... I should probably create a new bug, if so, could you please tell me the product to select?
> if I disable it afterwards using Alt+Shift+F12 it has no effect. iow not the compositor but the panel (an opengl context as well) flickers. Check uxa acceleration first https://wiki.archlinux.org/index.php/Intel_graphics#SNA_issues
(In reply to Thomas Lübking from comment #11) > > if I disable it afterwards using Alt+Shift+F12 it has no effect. > iow not the compositor but the panel (an opengl context as well) flickers. > > Check uxa acceleration first > https://wiki.archlinux.org/index.php/Intel_graphics#SNA_issues I've already tried switching from UXA to SNA like that, sadly it doesn't help.
(In reply to Florian Wolfsjäger from comment #12) > (In reply to Thomas Lübking from comment #11) > > > if I disable it afterwards using Alt+Shift+F12 it has no effect. > > iow not the compositor but the panel (an opengl context as well) flickers. > > > > Check uxa acceleration first > > https://wiki.archlinux.org/index.php/Intel_graphics#SNA_issues > > I've already tried switching from UXA to SNA like that, sadly it doesn't > help. The other way around, to UXA, sorry.