Created attachment 141182 [details]
kmsg trace

I am experiencing consistent, reproducible crashes when running games on my
Radeon R9-285 with amdgpu. My system also has a Ryzen 2700X on an Asus ROG
STRIX X470-F GAMING motherboard (latest firmware as of August 15, 2018). The
system is not overclocked.

Kernel: 4.18.1-arch1-1-ARCH #1 SMP PREEMPT Wed Aug 15 21:11:55 UTC 2018 x86_64
GNU/Linux

1. This occurs on any kernel from 4.15 to 4.18.
2. This DOES NOT occur on the kernel provided by the Arch linux-lts package
(kernel 4.14.63).

TO REPRODUCE: start Quake 3 Arena (or OpenArena), have 2 bots fight each other
and spectate one of them, and simply let the machine run until it crashes.
(Note: it happens in multiple other games but this is the easiest way to
reproduce it.) Sometimes it will happen immediately, sometimes it can run for
2-3 hours before a crash, but it will always crash eventually.

[See the attachment for a kmsg trace.]