Application: kwin_x11 (5.13.5)

Qt Version: 5.11.1
Frameworks Version: 5.50.0
Operating System: Linux 4.18.0-12-lowlatency x86_64
Distribution: Ubuntu 18.10

-- Information about the crash:
- What I was doing when the application crashed: Changement utilisateur 2 vers utilisateur 1 avec les 2 comptes actifs

The crash can be reproduced sometimes.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f5d66573840 (LWP 2609))]

Thread 8 (Thread 0x7f5d5d3ac700 (LWP 7500)):
#0  0x00007f5d6e33f2eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56511f2b9f64) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f5d6e33f2eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x56511f2b9f10, cond=0x56511f2b9f38) at pthread_cond_wait.c:502
#2  0x00007f5d6e33f2eb in __pthread_cond_wait (cond=0x56511f2b9f38, mutex=0x56511f2b9f10) at pthread_cond_wait.c:655
#3  0x00007f5d6f50943b in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f5d6dea0279 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007f5d6dea04da in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007f5d6f508c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7f5d5f7fe700 (LWP 7499)):
#0  0x00007f5d70b5e7d6 in __GI_ppoll (fds=0x7f5d5000bcb8, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f5d6f6ff141 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f5d6f7005b9 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f5d6f6b016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f5d6f4ff0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f5d6db6a1f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007f5d6f508c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f5d4e02b700 (LWP 3301)):
#0  0x00007f5d6e33f2eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56511ed8e240) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f5d6e33f2eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x56511ed8e1f0, cond=0x56511ed8e218) at pthread_cond_wait.c:502
#2  0x00007f5d6e33f2eb in __pthread_cond_wait (cond=0x56511ed8e218, mutex=0x56511ed8e1f0) at pthread_cond_wait.c:655
#3  0x00007f5d6f50943b in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f5d6dea0279 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007f5d6dea04da in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007f5d6f508c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f5d43fff700 (LWP 2726)):
#0  0x00007f5d6e33f2eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f5d6f11cfb8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f5d6e33f2eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f5d6f11cf68, cond=0x7f5d6f11cf90) at pthread_cond_wait.c:502
#2  0x00007f5d6e33f2eb in __pthread_cond_wait (cond=0x7f5d6f11cf90, mutex=0x7f5d6f11cf68) at pthread_cond_wait.c:655
#3  0x00007f5d6f025e2a in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#4  0x00007f5d6f025e49 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#5  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f5d5effd700 (LWP 2693)):
#0  0x00007f5d70b5e7d6 in __GI_ppoll (fds=0x7f5d54000d28, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f5d6f6ff141 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f5d6f7005b9 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f5d6f6b016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f5d6f4ff0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f5d6db6a1f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007f5d6f508c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f5d5ffff700 (LWP 2682)):
#0  0x00007f5d70b5e7d6 in __GI_ppoll (fds=0x7f5d5800b328, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f5d6f6ff141 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f5d6f7005b9 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f5d6f6b016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f5d6f4ff0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f5d6d64e545 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#6  0x00007f5d6f508c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f5d65741700 (LWP 2645)):
#0  0x00007f5d70b5e6d9 in __GI___poll (fds=0x7f5d65740c78, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f5d70663917 in  () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f5d7066553a in xcb_wait_for_event () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f5d65c23159 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007f5d6f508c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f5d6e339164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007f5d70b6adef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f5d66573840 (LWP 2609)):
[KCrash Handler]
#6  0x00007f5d6f2330b1 in  () at /usr/lib/x86_64-linux-gnu/libkwin4_effect_builtins.so.1
#7  0x00007f5d6f233174 in  () at /usr/lib/x86_64-linux-gnu/libkwin4_effect_builtins.so.1
#8  0x00007f5d6f2346d5 in  () at /usr/lib/x86_64-linux-gnu/libkwin4_effect_builtins.so.1
#9  0x00007f5d6f2350b3 in  () at /usr/lib/x86_64-linux-gnu/libkwin4_effect_builtins.so.1
#10 0x00007f5d708d6163 in KWin::EffectsHandlerImpl::drawWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#11 0x00007f5d6f1a3d29 in  () at /usr/lib/x86_64-linux-gnu/libkwin4_effect_builtins.so.1
#12 0x00007f5d708d6163 in KWin::EffectsHandlerImpl::drawWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#13 0x00007f5d6f297d6c in KWin::Effect::drawWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#14 0x00007f5d708d6163 in KWin::EffectsHandlerImpl::drawWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#15 0x00007f5d6f297d6c in KWin::Effect::drawWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#16 0x00007f5d708d6163 in KWin::EffectsHandlerImpl::drawWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#17 0x00007f5d708c28cc in KWin::Scene::finalPaintWindow(KWin::EffectWindowImpl*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#18 0x00007f5d708d5ffb in KWin::EffectsHandlerImpl::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#19 0x00007f5d6f297bfc in KWin::Effect::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#20 0x00007f5d708d5fa3 in KWin::EffectsHandlerImpl::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#21 0x00007f5d6f297bfc in KWin::Effect::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#22 0x00007f5d708d5fa3 in KWin::EffectsHandlerImpl::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#23 0x00007f5d6f2a466b in KWin::AnimationEffect::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#24 0x00007f5d708d5fa3 in KWin::EffectsHandlerImpl::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#25 0x00007f5d6f2a466b in KWin::AnimationEffect::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#26 0x00007f5d708d5fa3 in KWin::EffectsHandlerImpl::paintWindow(KWin::EffectWindow*, int, QRegion, KWin::WindowPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#27 0x00007f5d708c8cae in KWin::Scene::paintWindow(KWin::Scene::Window*, int, QRegion, KWin::WindowQuadList) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#28 0x00007f5d708c545c in KWin::Scene::paintSimpleScreen(int, QRegion) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#29 0x00007f5d641737d2 in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kwin.scenes/KWinSceneOpenGL.so
#30 0x00007f5d708c8280 in KWin::Scene::finalPaintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#31 0x00007f5d708d5d55 in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#32 0x00007f5d6f297b51 in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#33 0x00007f5d708d5cfd in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#34 0x00007f5d6f297b51 in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#35 0x00007f5d708d5cfd in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#36 0x00007f5d6f297b51 in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#37 0x00007f5d708d5cfd in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#38 0x00007f5d6f297b51 in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.11
#39 0x00007f5d708d5cfd in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#40 0x00007f5d708c7f2e in KWin::Scene::paintScreen(int*, QRegion const&, QRegion const&, QRegion*, QRegion*, QMatrix4x4 const&, QRect const&) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#41 0x00007f5d6417ace6 in KWin::SceneOpenGL::paint(QRegion, QList<KWin::Toplevel*>) () at /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kwin.scenes/KWinSceneOpenGL.so
#42 0x00007f5d708b9caa in KWin::Compositor::performCompositing() () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#43 0x00007f5d6f6daf4b in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#44 0x00007f5d700724a1 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#45 0x00007f5d70079ae0 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#46 0x00007f5d6f6b1499 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#47 0x00007f5d6f702558 in QTimerInfoList::activateTimers() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#48 0x00007f5d6f70070c in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#49 0x00007f5d65cb50ed in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#50 0x00007f5d6f6b016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#51 0x00007f5d6f6b82e2 in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#52 0x00007f5d70c4447b in kdemain () at /usr/lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#53 0x00007f5d70a7409b in __libc_start_main (main=0x56511d43c050, argc=3, argv=0x7ffee27ca9a8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffee27ca998) at ../csu/libc-start.c:308
#54 0x000056511d43c08a in _start ()
[Inferior 1 (process 2609) detached]

Reported using DrKonqi