https://bugs.freedesktop.org/show_bug.cgi?id=105251
--- Comment #14 from Barry G barry@grussling.com --- Did some more testing and found that I can cause this issue to happen repeatably by using Imagemagick convert to attempt to convert and resize a jpg image.
Doing the same convert and settings the environment variable MAGICK_OCL_DEVICE=OFF works without lockup.
Some sort of OpenCL thing?