https://bugs.freedesktop.org/show_bug.cgi?id=93801
--- Comment #14 from Maxim Sheviakov mrader3940@gmail.com --- (In reply to Michel Dänzer from comment #13)
There's no trace of the driver being involved in the hanging state. Based on that and José's comments, let's assume that this is a game bug.
Damn, that's interesting. I will try to attach gdb to game running with that line in its Steam options and search for anything different.