Created attachment 119583 [details]
Partial dmesg log where the GPU tries to reset itself and fails

I'm experiencing some random lockups whilst playing TF2.

There doesn't seem to be any particular cause, and they happen after a random
period of time (but still fairly often). There don't seem to be any
accompanying symptoms.

I've attached a relevant log, and the versions of relevant packages and other
info are listed below. Please let me know if I've missed anything, or if any
additional logs or dumps would be useful.

GPU - Radeon HD 4670
Mesa 11.0.4
LLVM 3.7.0-r2
libdrm 2.4.65
Linux kernel 4.3.0-gentoo