[Bug 98162] gpu hangs with unigine heaven on drm-next-4.9-wip

https://bugs.freedesktop.org/show_bug.cgi?id=98162

--- Comment #2 from Christoph Haag haagch@frickel.club --- Created attachment 127334 --> https://bugs.freedesktop.org/attachment.cgi?id=127334&action=edit gpu hang dmesg with counter strike: global offensive

To document this: csgo ran fine, although very slow with stock 4.9-rc1. I did not try for very long, so perhaps it would still have happened after a while.

The performance issue was identified to be caused by 87744ab3832b83ba71b931f86f9cfdb000d07da5

After reverting this commit on 4.9-rc1, I still do not get GPU hangs with unigine heaven, but I start seeing GPU hangs with csgo.

Maybe not the same issue, but it doesn't happen on 4.8.