https://bugs.freedesktop.org/show_bug.cgi?id=82186
--- Comment #9 from MirceaKitsune sonichedgehog_hyperblast00@yahoo.com --- Argh, I wish I could have found this report earlier! I discovered it by doing a Google search on commit edbbfac6cfc634e697d7f981155a5072c52d77ac which introduced the exact same lockup for my video card. I've been maintaining the following report for years now, about the same bug apparently:
https://bugs.freedesktop.org/show_bug.cgi?id=73528
So from what I understand, setting R600_DEBUG=notiling should prevent fast-clear from freezing the GPU? I will gladly try this for Second Life and other programs that trigger the problem, and see if there are any changes.