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Date: Thu, 16 Sep 2021 10:30:37 +0200
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>,
	edk2-devel-groups-io <devel@edk2.groups.io>,
	James Bottomley <jejb@linux.ibm.com>, Min Xu <min.m.xu@intel.com>,
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Subject: Re: [PATCH v7 09/31] OvmfPkg/SecMain: register GHCB gpa for the SEV-SNP guest
Message-ID: <20210916083037.cpkr2xo6ukpokfun@sirius.home.kraxel.org>
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  Hi,

> Good point, there is no reason to read and restore the old GHCB, I will
> remove it in next version. The function does not set this as a GHCB address,
> it send request to hypervisor saying that it would like to use this address.
> If hypervisor is not okay with the address then it may recommend something
> else. We don't support working with the hypervisor preferred address.
> Setting the GHCB address code is common between Snp and Es but checking with
> hypervisor whether its okay to use is new in the GHCBv2 and is SNP specific.

A comment explaining those GHCBv1 vs. GHCBv2 differences would be great.

thanks,
  Gerd