Application: kwin_x11 (5.10.5)

Qt Version: 5.7.1
Frameworks Version: 5.37.0
Operating System: Linux 4.10.0-33-generic x86_64
Distribution: Ubuntu 17.04

-- Information about the crash:
- What I was doing when the application crashed:
Logon from SDDM to KDE Plasma session.
Instead of the desktop, the crash window for KWin appeared.
Plasma and KWin (re)started automatically soon after.

The crash does not seem to be reproducible.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
[Current thread is 1 (Thread 0x7f0686a95580 (LWP 2064))]

Thread 7 (Thread 0x7f064f7fe700 (LWP 2464)):
#0  0x00007f067fba0510 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f0682ecc2c4 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007f0682ecc309 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007f067fb9a6da in start_thread (arg=0x7f064f7fe700) at pthread_create.c:456
#4  0x00007f06864ced7f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 6 (Thread 0x7f064ffff700 (LWP 2458)):
#0  0x00007f067fba08b9 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:225
#1  0x00007f0683b4da26 in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f0683b49252 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f0683b4cc38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f067fb9a6da in start_thread (arg=0x7f064ffff700) at pthread_create.c:456
#5  0x00007f06864ced7f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 5 (Thread 0x7f065dded700 (LWP 2206)):
[KCrash Handler]
#6  0x00007f0683cae973 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f0683c4b766 in QLockFile::tryLock(int) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f0685829389 in  () at /usr/lib/x86_64-linux-gnu/libKF5ConfigCore.so.5
#9  0x00007f0685813180 in KConfig::sync() () at /usr/lib/x86_64-linux-gnu/libKF5ConfigCore.so.5
#10 0x00007f0664f54175 in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kwin.platforms/KWinX11Platform.so
#11 0x00007f0683d47afe in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007f0683d54058 in QTimer::timerEvent(QTimerEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007f0683d485f3 in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007f06849f235c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#15 0x00007f06849f9b21 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#16 0x00007f0683d1bc00 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007f0683d6f03e in QTimerInfoList::activateTimers() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007f0683d6cf4a in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x00007f0683d19bea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00007f0683b47f83 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#21 0x00007f0683b4cc38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007f067fb9a6da in start_thread (arg=0x7f065dded700) at pthread_create.c:456
#23 0x00007f06864ced7f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 4 (Thread 0x7f065edee700 (LWP 2199)):
#0  0x00007f06864c2e51 in __GI_ppoll (fds=0x7f0650000ac8, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f0683d6b3e1 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f0683d6ccda in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f0683d19bea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f0683b47f83 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f067e907df5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007f0683b4cc38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f067fb9a6da in start_thread (arg=0x7f065edee700) at pthread_create.c:456
#8  0x00007f06864ced7f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 3 (Thread 0x7f065f5ef700 (LWP 2143)):
#0  0x00007f067fba08b9 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:225
#1  0x00007f0683b4da26 in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f0683b49252 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f0683b4cc38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f067fb9a6da in start_thread (arg=0x7f065f5ef700) at pthread_create.c:456
#5  0x00007f06864ced7f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 2 (Thread 0x7f066ce2d700 (LWP 2070)):
#0  0x00007f06864c2d8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f067b194576 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f067b19468c in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f0683d700bb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f0683d19bea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f0683b47f83 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f067dad65d5 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#7  0x00007f0683b4cc38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f067fb9a6da in start_thread (arg=0x7f066ce2d700) at pthread_create.c:456
#9  0x00007f06864ced7f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 1 (Thread 0x7f0686a95580 (LWP 2064)):
#0  0x00007f067fba0510 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f0683b4daeb in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f0683b4c7de in QThread::wait(unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f0664f53e1e in KWin::X11StandalonePlatform::createOpenGLSafePoint(KWin::Platform::OpenGLSafePoint) () at /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kwin.platforms/KWinX11Platform.so
#4  0x00007f068601df8d in KWin::Compositor::performCompositing() () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#5  0x00007f0683d485f3 in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f06849f235c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#7  0x00007f06849f9b21 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#8  0x00007f0683d1bc00 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f0683d6f03e in QTimerInfoList::activateTimers() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f0683d6cf4a in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007f0667db355d in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#12 0x00007f0683d19bea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007f0683d2233c in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007f0686796112 in kdemain () at /usr/lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#15 0x00007f06863e63f1 in __libc_start_main (main=0x5557bd3917e0, argc=1, argv=0x7fff56618178, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff56618168) at ../csu/libc-start.c:291
#16 0x00005557bd39181a in _start ()

Reported using DrKonqi