Application: kwin_x11 (5.11.5)

Qt Version: 5.10.0
Frameworks Version: 5.42.0
Operating System: Linux 4.14.14-1-ARCH x86_64
Distribution (Platform): Archlinux Packages

-- Information about the crash:
- What I was doing when the application crashed:
cycling the list of windows using ALT+TAB. the task switcher displays the window's  thumbnails to choose in a side-pop out. 

currently using vanilla archlinux updated as of 24/01/2018

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f3b6ec7d840 (LWP 2870))]

Thread 14 (Thread 0x7f3b46adb700 (LWP 2895)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 13 (Thread 0x7f3b21ffb700 (LWP 2893)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b6aac5f77 in  () at /usr/lib/libQt5Script.so.5
#2  0x00007f3b6aac5fb9 in  () at /usr/lib/libQt5Script.so.5
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 12 (Thread 0x7f3b22ffd700 (LWP 2891)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 11 (Thread 0x7f3b237fe700 (LWP 2890)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 10 (Thread 0x7f3b23fff700 (LWP 2889)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 9 (Thread 0x7f3b38ba4700 (LWP 2888)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 8 (Thread 0x7f3b393a5700 (LWP 2887)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 7 (Thread 0x7f3b39ba6700 (LWP 2886)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 6 (Thread 0x7f3b3a3a7700 (LWP 2885)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 5 (Thread 0x7f3b3acef700 (LWP 2884)):
#0  0x00007f3b674c539d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f3b443e6fbc in  () at /usr/lib/dri/radeonsi_dri.so
#2  0x00007f3b443e6ec8 in  () at /usr/lib/dri/radeonsi_dri.so
#3  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 4 (Thread 0x7f3b47d1c700 (LWP 2880)):
#0  0x00007f3b6e60ba16 in ppoll () at /usr/lib/libc.so.6
#1  0x00007f3b6bbc46f3 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#2  0x00007f3b6bbc5e8f in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007f3b6bb6ad0b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007f3b6b97a78e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#5  0x00007f3b65f7ba19 in  () at /usr/lib/libQt5Qml.so.5
#6  0x00007f3b6b97fb2d in  () at /usr/lib/libQt5Core.so.5
#7  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 3 (Thread 0x7f3b4e93f700 (LWP 2877)):
#0  0x00007f3b6e60ba16 in ppoll () at /usr/lib/libc.so.6
#1  0x00007f3b6bbc46f3 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#2  0x00007f3b6bbc5e8f in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007f3b6bb6ad0b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007f3b6b97a78e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#5  0x00007f3b650dc416 in  () at /usr/lib/libQt5DBus.so.5
#6  0x00007f3b6b97fb2d in  () at /usr/lib/libQt5Core.so.5
#7  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 2 (Thread 0x7f3b5502f700 (LWP 2875)):
#0  0x00007f3b6e60b91b in poll () at /usr/lib/libc.so.6
#1  0x00007f3b6d6fc8e0 in  () at /usr/lib/libxcb.so.1
#2  0x00007f3b6d6fe679 in xcb_wait_for_event () at /usr/lib/libxcb.so.1
#3  0x00007f3b5613d7aa in  () at /usr/lib/libQt5XcbQpa.so.5
#4  0x00007f3b6b97fb2d in  () at /usr/lib/libQt5Core.so.5
#5  0x00007f3b674bf08c in start_thread () at /usr/lib/libpthread.so.0
#6  0x00007f3b6e615e1f in clone () at /usr/lib/libc.so.6

Thread 1 (Thread 0x7f3b6ec7d840 (LWP 2870)):
[KCrash Handler]
#5  0x00007f3b447c5a00 in  () at /usr/lib/dri/radeonsi_dri.so
#6  0x00007f3b44522573 in  () at /usr/lib/dri/radeonsi_dri.so
#7  0x00007f3b4452061f in  () at /usr/lib/dri/radeonsi_dri.so
#8  0x00007f3b44522f43 in  () at /usr/lib/dri/radeonsi_dri.so
#9  0x00007f3b442fb958 in  () at /usr/lib/dri/radeonsi_dri.so
#10 0x00007f3b442fd42a in  () at /usr/lib/dri/radeonsi_dri.so
#11 0x00007f3b4427e6f3 in  () at /usr/lib/dri/radeonsi_dri.so
#12 0x00007f3b442801b0 in  () at /usr/lib/dri/radeonsi_dri.so
#13 0x00007f3b6665059e in QSGPlainTexture::bind() () at /usr/lib/libQt5Quick.so.5
#14 0x00007f3b6667740d in QSGPainterTexture::bind() () at /usr/lib/libQt5Quick.so.5
#15 0x00007f3b66651962 in QSGOpaqueTextureMaterialShader::updateState(QSGMaterialShader::RenderState const&, QSGMaterial*, QSGMaterial*) () at /usr/lib/libQt5Quick.so.5
#16 0x00007f3b6664157c in QSGBatchRenderer::Renderer::renderMergedBatch(QSGBatchRenderer::Batch const*) () at /usr/lib/libQt5Quick.so.5
#17 0x00007f3b66642966 in QSGBatchRenderer::Renderer::renderBatches() () at /usr/lib/libQt5Quick.so.5
#18 0x00007f3b666481de in QSGBatchRenderer::Renderer::render() () at /usr/lib/libQt5Quick.so.5
#19 0x00007f3b66638632 in QSGRenderer::renderScene(QSGBindable const&) () at /usr/lib/libQt5Quick.so.5
#20 0x00007f3b66638afc in QSGRenderer::renderScene(unsigned int) () at /usr/lib/libQt5Quick.so.5
#21 0x00007f3b66672c60 in QSGDefaultRenderContext::renderNextFrame(QSGRenderer*, unsigned int) () at /usr/lib/libQt5Quick.so.5
#22 0x00007f3b666d7110 in QQuickWindowPrivate::renderSceneGraph(QSize const&) () at /usr/lib/libQt5Quick.so.5
#23 0x00007f3b66664fb8 in  () at /usr/lib/libQt5Quick.so.5
#24 0x00007f3b666e2686 in QQuickWindow::event(QEvent*) () at /usr/lib/libQt5Quick.so.5
#25 0x00007f3b153eec64 in PlasmaQuick::Dialog::event(QEvent*) () at /usr/lib/libKF5PlasmaQuick.so.5
#26 0x00007f3b6c8e9e3c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#27 0x00007f3b6c8f1816 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#28 0x00007f3b6bb6c6c0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#29 0x00007f3b6c0eb7f3 in QWindowPrivate::deliverUpdateRequest() () at /usr/lib/libQt5Gui.so.5
#30 0x00007f3b6c0ebd2b in QWindow::event(QEvent*) () at /usr/lib/libQt5Gui.so.5
#31 0x00007f3b666e2626 in QQuickWindow::event(QEvent*) () at /usr/lib/libQt5Quick.so.5
#32 0x00007f3b153eec64 in PlasmaQuick::Dialog::event(QEvent*) () at /usr/lib/libKF5PlasmaQuick.so.5
#33 0x00007f3b6c8e9e3c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#34 0x00007f3b6c8f1816 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#35 0x00007f3b6bb6c6c0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#36 0x00007f3b6bbc7fb8 in QTimerInfoList::activateTimers() () at /usr/lib/libQt5Core.so.5
#37 0x00007f3b6bbc60f4 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#38 0x00007f3b561c558e in  () at /usr/lib/libQt5XcbQpa.so.5
#39 0x00007f3b6bb6ad0b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#40 0x00007f3b6bb73ff8 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5
#41 0x00007f3b6e8e06e3 in kdemain () at /usr/lib/libkdeinit5_kwin_x11.so
#42 0x00007f3b6e540f4a in __libc_start_main () at /usr/lib/libc.so.6
#43 0x00005556d00a77aa in _start ()

Reported using DrKonqi