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> Presumably bios code is in arch/x86 and drivers/acpi, right?
> Up to 200 calls the majority of which is likely private ...

Yes.

> I don't have better ideas but the current setup will just
> result in people making their guests vulnerable whenever they
> want to allow device pass-through.


Yes that's true. For current TDX our target is virtual devices only. But 
if pass through usage will be really wide spread we may need to revisit.


-Andi