Application: kwin_x11 (5.11.5)

Qt Version: 5.9.1
Frameworks Version: 5.41.0
Operating System: Linux 4.13.0-32-generic x86_64
Distribution: Ubuntu 17.10

-- Information about the crash:
- What I was doing when the application crashed:

browsing in google chrome, and hit alt-tab to switch to another application.

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 0x7f1b8596b940 (LWP 1412))]

Thread 5 (Thread 0x7f1b5292e700 (LWP 17957)):
#0  0x00007f1b8291ab25 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#1  0x00007f1b828c2e3a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f1b826e23ca in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f1b826e729d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f1b7e3017fc in start_thread (arg=0x7f1b5292e700) at pthread_create.c:465
#5  0x00007f1b85304b5f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f1b535ef700 (LWP 1565)):
#0  0x00007f1b7e308072 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f1b81b5afb8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f1b7e308072 in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f1b81b5af68, cond=0x7f1b81b5af90) at pthread_cond_wait.c:502
#2  0x00007f1b7e308072 in __pthread_cond_wait (cond=0x7f1b81b5af90, mutex=0x7f1b81b5af68) at pthread_cond_wait.c:655
#3  0x00007f1b81866bd4 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#4  0x00007f1b81866c19 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#5  0x00007f1b7e3017fc in start_thread (arg=0x7f1b535ef700) at pthread_create.c:465
#6  0x00007f1b85304b5f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f1b61b01700 (LWP 1523)):
#0  0x00007f1b852f8a4b in __GI_ppoll (fds=0x7f1b58000d38, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f1b82919151 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f1b8291a86e in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f1b828c2e3a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f1b826e23ca in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f1b7ce09f45 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007f1b826e729d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f1b7e3017fc in start_thread (arg=0x7f1b61b01700) at pthread_create.c:465
#8  0x00007f1b85304b5f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f1b63b68700 (LWP 1427)):
#0  0x00007f1b8291a7b5 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#1  0x00007f1b828c2e3a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f1b826e23ca in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f1b7bfcae45 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#4  0x00007f1b826e729d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f1b7e3017fc in start_thread (arg=0x7f1b63b68700) at pthread_create.c:465
#6  0x00007f1b85304b5f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f1b8596b940 (LWP 1412)):
[KCrash Handler]
#6  0x00007f1b74794bd0 in  () at /usr/lib/nvidia-384/libnvidia-glcore.so.384.111
#7  0x00007f1b7485b063 in  () at /usr/lib/nvidia-384/libnvidia-glcore.so.384.111
#8  0x00007f1b7485f864 in  () at /usr/lib/nvidia-384/libnvidia-glcore.so.384.111
#9  0x00007f1b74868a84 in  () at /usr/lib/nvidia-384/libnvidia-glcore.so.384.111
#10 0x00007f1b74427a5e in  () at /usr/lib/nvidia-384/libnvidia-glcore.so.384.111
#11 0x00007f1b7d4b231f in QSGBatchRenderer::Renderer::renderMergedBatch(QSGBatchRenderer::Batch const*) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#12 0x00007f1b7d4b3555 in QSGBatchRenderer::Renderer::renderBatches() () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#13 0x00007f1b7d4b8cac in QSGBatchRenderer::Renderer::render() () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#14 0x00007f1b7d4a966d in QSGRenderer::renderScene(QSGBindable const&) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#15 0x00007f1b7d4a9b2b in QSGRenderer::renderScene(unsigned int) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#16 0x00007f1b7d4e3f50 in QSGDefaultRenderContext::renderNextFrame(QSGRenderer*, unsigned int) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#17 0x00007f1b7d5409b8 in QQuickWindowPrivate::renderSceneGraph(QSize const&) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#18 0x00007f1b7d4d6399 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#19 0x00007f1b7d54ad66 in QQuickWindow::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#20 0x00007f1b51297be3 in PlasmaQuick::Dialog::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libKF5PlasmaQuick.so.5
#21 0x00007f1b8363f46c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#22 0x00007f1b83646d34 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#23 0x00007f1b828c4de8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#24 0x00007f1b82e8fb01 in QWindowPrivate::deliverUpdateRequest() () at /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#25 0x00007f1b82e90019 in QWindow::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#26 0x00007f1b7d54ad05 in QQuickWindow::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#27 0x00007f1b51297be3 in PlasmaQuick::Dialog::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libKF5PlasmaQuick.so.5
#28 0x00007f1b8363f46c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#29 0x00007f1b83646d34 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#30 0x00007f1b828c4de8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#31 0x00007f1b8291c91e in QTimerInfoList::activateTimers() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#32 0x00007f1b8291aad2 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#33 0x00007f1b6b18d9ad in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#34 0x00007f1b828c2e3a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#35 0x00007f1b828cbda4 in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#36 0x00007f1b855d8db6 in kdemain () at /usr/lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#37 0x00007f1b852111c1 in __libc_start_main (main=0x55b6501d87b0, argc=1, argv=0x7ffdc595f668, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffdc595f658) at ../csu/libc-start.c:308
#38 0x000055b6501d87ea in _start ()

Reported using DrKonqi