(In reply to L.S.S. from comment #188)
> Not sure where the problem might be.
> 
> After installing 5.4-rc5, in addition to amdgpu-pro-libgl (and other
> amdgpu-pro related stuffs), I stopped encountering those dreaded "ring sdma0
> timeout" freezes when using Nemo. I think amdgpu-pro stuffs might be what
> "fixed" it.
> 
> I'll test this for the time being. I cannot be confident that it would be
> completely fixed this way, but at least the situation has been improved to
> the point that Nemo is now usable again.

As I said in comment #149
(https://bugs.freedesktop.org/show_bug.cgi?id=111481#c149), amdgpu-pro does not
exhibit freezes or timeouts.

This appears to point to a problem in the generated instructions from libgl (or
potentially a combination of that plus an underlying issue in the kernel
driver).