Bug 381076

Application: kwin_x11 (5.10.1)

Qt Version: 5.9.0
Frameworks Version: 5.34.0
Operating System: Linux 4.11.3-2-zen x86_64
Distribution (Platform): Archlinux Packages

-- Information about the crash:
- What I was doing when the application crashed:
I pressed Alt+Tab to show the Window changer and it hung and crashed.

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 0x7f8792a88840 (LWP 5001))]

Thread 11 (Thread 0x7f8753507700 (LWP 5026)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f878e9c3ac4 in  () at /usr/lib/libQt5Script.so.5
#2  0x00007f878e9c3b09 in  () at /usr/lib/libQt5Script.so.5
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 10 (Thread 0x7f8754509700 (LWP 5024)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f875f4d971b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#2  0x00007f875f4d9447 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 9 (Thread 0x7f8754d0a700 (LWP 5023)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f875f4d971b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#2  0x00007f875f4d9447 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 8 (Thread 0x7f875cb81700 (LWP 5022)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f875f4d971b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#2  0x00007f875f4d9447 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 7 (Thread 0x7f875d382700 (LWP 5021)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f875f4d971b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#2  0x00007f875f4d9447 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 6 (Thread 0x7f875dd8a700 (LWP 5020)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f875f4d971b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#2  0x00007f875f4d9447 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 5 (Thread 0x7f875e6d2700 (LWP 5019)):
#0  0x00007f878b60039d in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f875f4d971b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#2  0x00007f875f4d9447 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#3  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 4 (Thread 0x7f876b64f700 (LWP 5017)):
#0  0x00007f87924be396 in ppoll () at /usr/lib/libc.so.6
#1  0x00007f878faac471 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#2  0x00007f878faadb5e in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007f878fa5721a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007f878f87940a in QThread::exec() () at /usr/lib/libQt5Core.so.5
#5  0x00007f878a30a645 in  () at /usr/lib/libQt5Qml.so.5
#6  0x00007f878f87dcbd in  () at /usr/lib/libQt5Core.so.5
#7  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 3 (Thread 0x7f8772a92700 (LWP 5005)):
#0  0x00007f87924be396 in ppoll () at /usr/lib/libc.so.6
#1  0x00007f878faac471 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#2  0x00007f878faadb5e in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007f878fa5721a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007f878f87940a in QThread::exec() () at /usr/lib/libQt5Core.so.5
#5  0x00007f87894a0d45 in  () at /usr/lib/libQt5DBus.so.5
#6  0x00007f878f87dcbd in  () at /usr/lib/libQt5Core.so.5
#7  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 2 (Thread 0x7f8778d4a700 (LWP 5003)):
#0  0x00007f87924be2bd in poll () at /usr/lib/libc.so.6
#1  0x00007f879158f8e0 in  () at /usr/lib/libxcb.so.1
#2  0x00007f8791591679 in xcb_wait_for_event () at /usr/lib/libxcb.so.1
#3  0x00007f8779e44d49 in  () at /usr/lib/libQt5XcbQpa.so.5
#4  0x00007f878f87dcbd in  () at /usr/lib/libQt5Core.so.5
#5  0x00007f878b5fa297 in start_thread () at /usr/lib/libpthread.so.0
#6  0x00007f87924c825f in clone () at /usr/lib/libc.so.6

Thread 1 (Thread 0x7f8792a88840 (LWP 5001)):
[KCrash Handler]
#6  0x00007f875f89968b in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#7  0x00007f875f608f25 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#8  0x00007f875f3e4940 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#9  0x00007f875f3a4b30 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#10 0x00007f875f3a4fb9 in  () at /usr/lib/xorg/modules/dri/radeonsi_dri.so
#11 0x00007f878a9c027f in QSGBatchRenderer::Renderer::renderMergedBatch(QSGBatchRenderer::Batch const*) () at /usr/lib/libQt5Quick.so.5
#12 0x00007f878a9c14c5 in QSGBatchRenderer::Renderer::renderBatches() () at /usr/lib/libQt5Quick.so.5
#13 0x00007f878a9c6c24 in QSGBatchRenderer::Renderer::render() () at /usr/lib/libQt5Quick.so.5
#14 0x00007f878a9b75cd in QSGRenderer::renderScene(QSGBindable const&) () at /usr/lib/libQt5Quick.so.5
#15 0x00007f878a9b7a8b in QSGRenderer::renderScene(unsigned int) () at /usr/lib/libQt5Quick.so.5
#16 0x00007f878a9f1d40 in QSGDefaultRenderContext::renderNextFrame(QSGRenderer*, unsigned int) () at /usr/lib/libQt5Quick.so.5
#17 0x00007f878aa4e868 in QQuickWindowPrivate::renderSceneGraph(QSize const&) () at /usr/lib/libQt5Quick.so.5
#18 0x00007f878a9e4139 in  () at /usr/lib/libQt5Quick.so.5
#19 0x00007f878aa58ad6 in QQuickWindow::event(QEvent*) () at /usr/lib/libQt5Quick.so.5
#20 0x00007f873a9227ab in PlasmaQuick::Dialog::event(QEvent*) () at /usr/lib/libKF5PlasmaQuick.so.5
#21 0x00007f879078746c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#22 0x00007f879078ecf4 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#23 0x00007f878fa58b98 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#24 0x00007f878ffce751 in QWindowPrivate::deliverUpdateRequest() () at /usr/lib/libQt5Gui.so.5
#25 0x00007f878ffcec69 in QWindow::event(QEvent*) () at /usr/lib/libQt5Gui.so.5
#26 0x00007f878aa58a75 in QQuickWindow::event(QEvent*) () at /usr/lib/libQt5Quick.so.5
#27 0x00007f873a9227ab in PlasmaQuick::Dialog::event(QEvent*) () at /usr/lib/libKF5PlasmaQuick.so.5
#28 0x00007f879078746c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#29 0x00007f879078ecf4 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#30 0x00007f878fa58b98 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#31 0x00007f878faafbae in QTimerInfoList::activateTimers() () at /usr/lib/libQt5Core.so.5
#32 0x00007f878faaddc2 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#33 0x00007f8779ea75bd in  () at /usr/lib/libQt5XcbQpa.so.5
#34 0x00007f878fa5721a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#35 0x00007f878fa5fa74 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5
#36 0x00007f879278bfd5 in kdemain () at /usr/lib/libkdeinit5_kwin_x11.so
#37 0x00007f87923fb43a in __libc_start_main () at /usr/lib/libc.so.6
#38 0x000000000040069a in _start ()

Reported using DrKonqi