On 6/22/22 11:34, Kalra, Ashish wrote:
>> So, if the RMP entry format changes in future processors, how do we
>> make sure that the kernel does not try to use *this* code on those
>> processors?
> Functions snp_lookup_rmpentry() and dump_rmpentry() which rely on
> this structure definition will need to handle it accordingly.

>In other words, old kernels will break on new >hardware?

>I think that needs to be fixed.  It should be as >simple as a
>model/family check, though.  If someone (for >example) attempts to use
>SNP (and thus snp_lookup_rmpentry() and >dump_rmpentry()) code on a newer
>CPU, the kernel should refuse.

More specifically I am thinking of adding RMP entry field accessors so that they can do this cpu model/family check and return the correct field as per processor architecture.

Thanks,

Ashish