Created attachment 133658 [details]
Generated by crash reporter. Wouldn't let me login though, so saved.

Application: kwin_x11 (5.19.5)

Qt Version: 5.14.2
Frameworks Version: 5.74.0
Operating System: Linux 5.8.0-29-generic x86_64
Windowing system: X11
Distribution: Ubuntu 20.10

-- Information about the crash:
<In detail, tell us what you were doing  when the application crashed.>

Running an AMD Ryzen 5 3400G APU, using amdgpu driver. Trying to get OpenCL working so I can run distributed.net RC5-72. Have a half install of amdgpu-pro, but install didn't work. Something about dkms not able to build. However, it installed enough so that dnetc runs. That was running in the background while watching a Twitch stream, went to type in chat and then kwin crashed and came back. Screens blanked for a second. Able to type in Twitch chat ok now. Firefox v83 with WebRender enabled.

So driver running is amdgpu, not amdgpu-pro. But parts of amdgpu-pro's OpenCL bits are installed. Enough that dnetc runs.

The crash does not seem to be reproducible.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault

[KCrash Handler]
#4  0x00007fd8b7892747 in QTimerInfoList::unregisterTimer(int) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fd8b783997a in QBasicTimer::stop() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fd8b8b81b89 in KWin::Compositor::performCompositing() () from /usr/lib/x86_64-linux-gnu/libkwin.so.5
#7  0x00007fd8b786858f in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fd8b82f2013 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#9  0x00007fd8b783c1ca in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007fd8b7892b73 in QTimerInfoList::activateTimers() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007fd8b7890fd7 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007fd8b12f0732 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#13 0x00007fd8b783aa4b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007fd8b7842fc6 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x000055fc5ccffa6d in ?? ()
#16 0x00007fd8b71c2cb2 in __libc_start_main (main=0x55fc5ccff6a0, argc=1, argv=0x7ffcc19ab288, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffcc19ab278) at ../csu/libc-start.c:314
#17 0x000055fc5ccfff8e in _start ()
[Inferior 1 (process 1660) detached]