(In reply to comment #30)
> (In reply to comment #29)
> > Just in case, I went back in time for bisection between v3.11 and v3.10,
> > began at commit 69e0b57a91adca2e3eb56ed4db39ab90f3ae1043 when dpm was
> > implemented on Cayman. I applied patches from bug 68235 so I could run
> > without display hanging. I've been running videos, daily tasks and piglit
> > runs without a crash. I'll move forward and see if I can find something that
> > could help us explain the hangs happening since v3.11.0.
> 
> As I mentioned in bug 68235, with 69e0b57a91adca2e3eb56ed4db39ab90f3ae1043
> the driver did not enable dynamic performance level adjustments since it
> caused hangs. With that commit the GPU always stays in the lowest
> performance level which is why it's stable.  The hangs were fixed by
> 4da18e26e0cc2387597ff57ac33df1bc6369fbed,
> 7a80c2c9a957b1ab056fac235140ebd6c43d9831, and
> 779187f2c3e69b8c06488538e0fd9fd02163359e and dynamic performance levels were
> enabled in commit 7ad8d0687bb5030c3328bc7229a3183ce179ab25.

Yes, I know. I just needed to start with something "solid". If running at the
lowest performances is stable, it gives me a reference. I had time to test
another commit in the branch, but since I'm not at home, I can't say if all the
commits you had identified are in. I'll probably continue tonight.