On Tue, Jun 28, 2022 at 02:35:51PM +0530, Vasant Hegde wrote:
> Sorry. I didn't get last statement ("device identity maps DMA requests 
> without PASID").
> Can you please elaborate?

When using v1 page-tables, each device supporting ATS/PRI/PASID needs to
be direct-mapped, because the v1 page-tables basically act as a stage-2
page table for the PASID ones.

But when the non-pasid case moves to the pasid==0 page-table, then there
is not stage-2 anymore and a device can be used with ATS/PRI/PASID while
non-PASID requests are translated too, no?

I didn't get how this is handled in the current patch-set.


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