Application: kwin_x11 (5.9.4)

Qt Version: 5.7.1
Frameworks Version: 5.31.0
Operating System: Linux 4.10.0-20-generic x86_64
Distribution: Ubuntu 17.04

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

Setting up a virtual machine using Oracle Virtual Box version 5.1.18 (Just closed the virtual machine Settings window by clicking OK). The error reproduces constantly whenever I do the same thing.

- Unusual behavior I noticed:

This error also happens when I'm using Gwenview, sometimes  when I start it, other times when I move or resize the window, but it's not constant. The whole desktop restarts, and the windows move around a bit when it starts again.

The crash can be reproduced every time.

-- 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 0x7fa5f76f5980 (LWP 1808))]

Thread 6 (Thread 0x7fa5cacb9700 (LWP 2258)):
#0  0x00007fa5f0828510 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007fa5f47cab4b in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa5efc59495 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#3  0x00007fa5efc59d8a in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#4  0x00007fa5f47c9c98 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa5f08226da in start_thread (arg=0x7fa5cacb9700) at pthread_create.c:456
#6  0x00007fa5f712e17f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 5 (Thread 0x7fa5bb5ef700 (LWP 1968)):
#0  0x00007fa5f7122251 in __GI_ppoll (fds=0x7fa5b4000ae8, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007fa5f49e9251 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa5f49eab4a in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa5f499788a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa5f47c4fe3 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa5ef58fdf5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007fa5f47c9c98 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fa5f08226da in start_thread (arg=0x7fa5bb5ef700) at pthread_create.c:456
#8  0x00007fa5f712e17f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 4 (Thread 0x7fa5ba604700 (LWP 1914)):
#0  0x00007fa5f0828510 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007fa5f3b532c4 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007fa5f3b53309 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007fa5f08226da in start_thread (arg=0x7fa5ba604700) at pthread_create.c:456
#4  0x00007fa5f712e17f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 3 (Thread 0x7fa5c97f3700 (LWP 1906)):
#0  0x00007fa5f7122251 in __GI_ppoll (fds=0x7fa5c0000ae8, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007fa5f49e9251 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa5f49eab4a in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa5f499788a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa5f47c4fe3 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa5ef58fdf5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007fa5f47c9c98 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fa5f08226da in start_thread (arg=0x7fa5c97f3700) at pthread_create.c:456
#8  0x00007fa5f712e17f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 2 (Thread 0x7fa5db833700 (LWP 1821)):
#0  0x00007fa5f712218d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fa5ebd4c576 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fa5ebd4c68c in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fa5f49edf2b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa5f499788a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa5f47c4fe3 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fa5ee7685c5 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#7  0x00007fa5f47c9c98 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fa5f08226da in start_thread (arg=0x7fa5db833700) at pthread_create.c:456
#9  0x00007fa5f712e17f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105

Thread 1 (Thread 0x7fa5f76f5980 (LWP 1808)):
[KCrash Handler]
#6  0xfffffffffd004000 in  ()
#7  0x00007fa5f49cb6e0 in QObject::connect(QObject const*, char const*, QObject const*, char const*, Qt::ConnectionType) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fa5f3b94037 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#9  0x00007fa5f3b940ff in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#10 0x00007fa5f3b94382 in QScriptEngine::newQObject(QObject*, QScriptEngine::ValueOwnership, QFlags<QScriptEngine::QObjectWrapOption> const&) () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#11 0x00007fa5f6d0a95f in  () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#12 0x00007fa5f3b945e5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#13 0x00007fa5f3bbbbf6 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#14 0x00007fa5f3bc3ba1 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#15 0x00007fa5f49c5644 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007fa5f4184e28 in KWin::EffectsHandler::desktopPresenceChanged(KWin::EffectWindow*, int, int) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.10
#17 0x00007fa5f41867f1 in  () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.10
#18 0x00007fa5f49c6359 in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x00007fa5f567135c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#20 0x00007fa5f5678b11 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#21 0x00007fa5f49998a0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007fa5f499c02d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#23 0x00007fa5f49ea977 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#24 0x00007fa5da9079fd in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#25 0x00007fa5f499788a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#26 0x00007fa5f499fffc in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#27 0x00007fa5f73f6112 in kdemain () at /usr/lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#28 0x00007fa5f70463f1 in __libc_start_main (main=0x558022ee67e0, argc=1, argv=0x7ffdc0eb0d18, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffdc0eb0d08) at ../csu/libc-start.c:291
#29 0x0000558022ee681a in _start ()

Reported using DrKonqi