Re: [PATCH 1/2] KVM: SEV: IBPB-on-Entry guest support

[Borislav Petkov]

On Mon, Feb 02, 2026 at 10:09:19AM -0600, Tom Lendacky wrote:
> But I can see that getting stale because it isn't required to be updated
> for features that don't require an implementation in order for the guest
> to boot successfully. Whereas the SNP_FEATURES_IMPL_REQ is set with
> known values that require an implementation and all the reserved bits
> set. So it takes actual updating to get one of those features to work
> that are represented in that bitmap.

Ok, I guess we can rename that define SNP_FEATURES_IMPL to denote is the
counterpart of SNP_FEATURES_IMPL_REQ, so to speak.

@Kim, you can send a new version with the define renamed.

Due to it being too close to the merge window, it'll wait for after and then
it can go to stable later but I don't think that's a problem.

> That will tell us what the guest is running with, not what it can run with.

hm, ok, let's think about this more then. I don't have a clear use case for
a this-is-what-a-SNP-guest-can-run-with so let's deal with that later...

Thx.

-- 
Regards/Gruss,
    Boris.

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