Re: [edk2-devel] [PATCH v12 32/32] UefiCpuPkg/MpInitLib: Use SEV-SNP AP Creation NAE event to launch APs

["Ni, Ray" <ray.ni@intel.com>]

Acked-by: Ray Ni <ray.ni@intel.com>

3 comments:

1. It seems to me that the latest SevSnp doesn't need much special handling in AP waking up flow.
     Is there a plan to drop the old SevEs so that the MpInitLib logic can have a chance to be back to normal?

>  [Sources.IA32]
> +  Ia32/AmdSev.c
>    Ia32/MpFuncs.nasm
> 
>  [Sources.X64]
> +  X64/AmdSev.c
>    X64/MpFuncs.nasm

2. I am not sure if it's a good idea that "THREE" files share the same name. Any objections from others?

> @@ -1056,9 +1057,12 @@ AllocateResetVector (
>                                      );
>      //
>      // The AP reset stack is only used by SEV-ES guests. Do not allocate it
> -    // if SEV-ES is not enabled.
> +    // if SEV-ES is not enabled. An SEV-SNP guest is also considered
> +    // an SEV-ES guest, but uses a different method of AP startup, eliminating
> +    // the need for the allocation.
>      //
> -    if (ConfidentialComputingGuestHas (CCAttrAmdSevEs)) {
> +    if (ConfidentialComputingGuestHas (CCAttrAmdSevEs) &&
> +        !ConfidentialComputingGuestHas (CCAttrAmdSevSnp)) {

3. Can you use "CpuMpData->UseSevEsAPMethod" in above if check?