RE: [PATCH Part2 v6 06/49] x86/sev: Add helper functions for RMPUPDATE and PSMASH instruction

Kalra, Ashish
2022-08-01T23:32:33Z

[AMD Official Use Only - General]

Hello Boris,

>> Yes, I will be adding a check for CPU family/model as following :

>Why if the PPR is already kinda spelling the already architectural pieces of the RMP entry?

>"In order to assist software" it says.

The PPR specifies select portions of the RMP entry format for a specific core/platform.

Therefore, the complete struct rmpentry definition is non-architectural.

As per PPR, software should not rely on any field definitions not specified
in this table and the format of an RMP entry may change in future processors.

>So you call the specified ones by their name and the rest is __rsvd.

>No need for model checks at all.

>Right?

But we can't use this struct on a core/platform which has a different layout, so aren't
the model checks required ?

Thanks,
Ashish