Re: [PATCH Part1 RFC v4 02/36] x86/sev: Save the negotiated GHCB version

From: Brijesh Singh
Date: Tue Aug 10 2021 - 09:17:10 EST




On 8/10/21 5:01 AM, Borislav Petkov wrote:
On Wed, Jul 07, 2021 at 01:14:32PM -0500, Brijesh Singh wrote:
The SEV-ES guest calls the sev_es_negotiate_protocol() to negotiate the
GHCB protocol version before establishing the GHCB. Cache the negotiated
GHCB version so that it can be used later.

Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
arch/x86/include/asm/sev.h | 2 +-
arch/x86/kernel/sev-shared.c | 17 ++++++++++++++---
2 files changed, 15 insertions(+), 4 deletions(-)

Also, while looking at this, all those defines in sev-common.h were
bothering me for a while now because they're an unreadable mess because
I have to go look at the GHCB spec, decode the corresponding MSR
protocol request and then go and piece together each request value by
verifying the masks...

So I did the below which is, IMO, a lot more readable as you can follow
it directly with the spec opened in parallel.

Thus, if you don't have a better idea, I'd ask you to please add this to
your set and continue defining the new MSR protocol requests this way so
that it can be readable.


thanks Boris, I will include this in my series and rework the remaining patches to align with it.

-brijesh