Application: kwin_x11 (5.12.6)

Qt Version: 5.9.5
Frameworks Version: 5.44.0
Operating System: Linux 4.15.0-36-generic x86_64
Distribution: Ubuntu 18.04.1 LTS

-- Information about the crash:
I was attempting to save a desktop session from the K-menu / Leave

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin_x11), signal: Aborted
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f625bbc2cc0 (LWP 17543))]

Thread 5 (Thread 0x7f621aa1f700 (LWP 17555)):
#0  0x00007f62545839f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f6257b1afb8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x7f6257b1af68, cond=0x7f6257b1af90) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x7f6257b1af90, mutex=0x7f6257b1af68) at pthread_cond_wait.c:655
#3  0x00007f62578245f4 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#4  0x00007f6257824639 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#5  0x00007f625457d6db in start_thread (arg=0x7f621aa1f700) at pthread_create.c:463
#6  0x00007f625b52388f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f623923b700 (LWP 17552)):
#0  0x00007f625b516cf6 in __GI_ppoll (fds=0x7f6230000d28, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f62589185c1 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f6258919cde in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f62588c19ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f62586e022a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f62530696f5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007f62586e516d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f625457d6db in start_thread (arg=0x7f623923b700) at pthread_create.c:463
#8  0x00007f625b52388f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f623bb68700 (LWP 17549)):
#0  0x00007f625b516cf6 in __GI_ppoll (fds=0x7f623400e7b8, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f62589185c1 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f6258919cde in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f62588c19ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f62586e022a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f6251f42d45 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#6  0x00007f62586e516d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f625457d6db in start_thread (arg=0x7f623bb68700) at pthread_create.c:463
#8  0x00007f625b52388f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f6242237700 (LWP 17547)):
#0  0x00007f625b516bf9 in __GI___poll (fds=0x7f6242236c68, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f625a420747 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f625a42236a in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f62431162a9 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007f62586e516d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f625457d6db in start_thread (arg=0x7f6242237700) at pthread_create.c:463
#6  0x00007f625b52388f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f625bbc2cc0 (LWP 17543)):
[KCrash Handler]
#6  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#7  0x00007f625b442801 in __GI_abort () at abort.c:79
#8  0x00007f62586cffa7 in QMessageLogger::fatal(char const*, ...) const () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f625b02549b in KWin::Workspace::windowTypeToTxt(NET::WindowType) () from /usr/lib/x86_64-linux-gnu/libkwin.so.5
#10 0x00007f625b026b40 in KWin::Workspace::storeClient(KConfigGroup&, int, KWin::Client*) () from /usr/lib/x86_64-linux-gnu/libkwin.so.5
#11 0x00007f625b02a2e8 in KWin::Workspace::storeSession(KConfig*, KWin::SMSavePhase) () from /usr/lib/x86_64-linux-gnu/libkwin.so.5
#12 0x00007f625b02a53d in KWin::Workspace::saveState(QSessionManager&) () from /usr/lib/x86_64-linux-gnu/libkwin.so.5
#13 0x00007f62588f26cf in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007f6258e7b445 in QGuiApplication::saveStateRequest(QSessionManager&) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#15 0x00007f6258e7cf9b in QGuiApplicationPrivate::saveState() () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#16 0x00007f62431470d8 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#17 0x00007f62564fb39e in _SmcProcessMessage () from /usr/lib/x86_64-linux-gnu/libSM.so.6
#18 0x00007f625670f978 in IceProcessMessages () from /usr/lib/x86_64-linux-gnu/libICE.so.6
#19 0x00007f62588f25b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00007f62588fea38 in QSocketNotifier::activated(int, QSocketNotifier::QPrivateSignal) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#21 0x00007f62588fee02 in QSocketNotifier::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007f625964182c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#23 0x00007f62596490f4 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#24 0x00007f62588c39a8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#25 0x00007f6258919988 in QEventDispatcherUNIXPrivate::activateSocketNotifiers() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#26 0x00007f625891a008 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#27 0x00007f62431795cd in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#28 0x00007f62588c19ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#29 0x00007f62588caa84 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#30 0x00007f625b7fbdbb in kdemain () from /usr/lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#31 0x00007f625b423b97 in __libc_start_main (main=0x558b8e550730, argc=3, argv=0x7ffe697a6878, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe697a6868) at ../csu/libc-start.c:310
#32 0x0000558b8e55076a in _start ()

Possible duplicates by query: bug 396297, bug 395743, bug 395712, bug 395282, bug 392092.

Reported using DrKonqi