Created attachment 141522 [details]
Logs + trace with patched mesa, plus example code which consistently triggers
crash.

I've been experiencing a random crash which seems a lot like this; the image
freezes, the keyboard stops working, the mouse can still be moved for a second
then also freezes, and the "GPU usage" leds all light and the fans spin up.

Oddly enough, while working on a toy opengl program I seem to have accidentally
found a means of consistently triggering it. I've included the sources in the
tarball; I didn't try and narrow down the exact cause, so please pardon any
extra fluff which is no doubt in there.

I at least captured a trace which contains the string "Buffer list". I also
noticed umr was spitting quite a bit of stuff out to stderr which isn't in the
dump; if you want that too let me know.

Some version numbers:
Radeon RX Vega 64
Linux amd-staging-drm-next 4.19.0-rc1-d0a96214993c
Mesa 18.3.0-devel (git-133e12fb69) (with the si_debug.c patch applied)