Re: [PATCH] x86/Hyper-V: Add SEV negotiate protocol support in Isolation VM

From: Tianyu Lan
Date: Fri May 06 2022 - 02:47:20 EST


On 5/5/2022 11:47 PM, Andrea Parri wrote:
On Thu, May 05, 2022 at 09:15:02AM -0400, Tianyu Lan wrote:
From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>

Hyper-V Isolation VM code uses sev_es_ghcb_hv_call() to read/write MSR
via GHCB page. The SEV-ES guest should negotiate GHCB version before
reading/writing MSR via GHCB page. Expose sev_es_negotiate_protocol()
and sev_es_terminate() from AMD SEV code and negotiate GHCB version in
hyperv_init_ghcb() fro Hyper-V Isolation VM.

Signed-off-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>

Applied to tip's x86/sev and checked that this can fix the regression (to
be introduced) by commit 2ea29c5abbc2 ("x86/sev: Save the negotiated GHCB
version"):

Tested-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx>

Nits: (in the commit message) fro -> for, Isolation VM -> Isolated VM


Nice catch! Thanks.