Created attachment 133806 [details]
Backtrace of the kwin crash

I use an AMD RX560 with Mesa 17.1.7 and Plasma 5.10.5 (ArchLinux).

When I use the "thumbnails" Alt+Tab style for kwin, sooner or later kwin will
segfault while alt+tabbing.
Without windows thumbnails, everything works ok.

I reported this bug on the KDE bugtracker already :
https://bugs.kde.org/show_bug.cgi?id=383058

But the crash seems to come from the driver.
It happened with previous Mesa 17.1 versions too.

See the backtrace in attachment.