(In reply to comment #8)
> So if CPU usage is drastically increased by this commit (or rather this
> merge), IMHO that points to a bug somewhere else, but triggered by this
> merge; possibly in radeon / TTM caching setup or in the x86 PAT memory
> region tracking code.
> 

 Seems like that is the case... VM_PFNMAP usage instead of VM_MIXEDMAP triggers
that i now need 'nopat' boot option it is also workaround...  

 So only 'nopat' option work here good with VM_PFNMAP or like before
VM_MIXEDMAP is good with PAT... VM_PFNMAP with PAT here is really unusable for
gl videos :).