(In reply to comment #135)
> (In reply to comment #134)
> > I'd like to test disabling UVD. I'll dig in the kernel to report UVD as
> > disabled for SI for this test. This should narrow where we have to look for
> > this bug.
> 
> Sometimes UVD functions are needed for power management to work correctly,
> so not enabling UVD at all might not be an option either. But I'm not sure
> if that applies to your hardware or not.
> 
> Easiest way to disable UVD otherwise is to just add an "return -1" to the
> beginning of radeon_uvd_init in the kernel module.

Well, when disabling UVD as suggested, I had no hang when viewing movies all
night long. No ring 5 error either.

I did get some Packet0 errors though, which were "stuttering" the display for
short times, but it never crashed.

However, at one point, Xorg just froze (the sound was still playing and the
mouse was moving but nothing  else was responding) but I think it is a
different bug (there is nothing in dmesg, but there is errors in Xorg.0.log).
I'll attach the file in a second. If someone is sure this is a different bug,
let me know so I'll open a new bug for it.

Overall, I'd be tempted to point at UVD for the current bug.