On Wed, May 12, 2021 at 09:03:41AM -0500, Brijesh Singh wrote:

Version 2 of the spec adds bunch of NAEs, and several of them are
optional except the hyervisor features NAE. IMO, a guest should bump the
GHCB version only after it has implemented all the required NAEs from
the version 2. It may help during the git bisect of the guest kernel --
mainly when the hypervisor supports the higher version.

Aha, so AFAICT, the version bump should happen in patch 3 which adds
that HV features NAE - not in a separate one after that. The logic
being, with the patch which adds the functionality needed, you mark the
guest as supporting v2.

-- 
Regards/Gruss,
    Boris.

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