Re: [PATCH v9 01/24] virt: sev-guest: Use AES GCM crypto library

Nikunj A. Dadhania
2024-06-13T03:40:52Z

On 6/12/2024 10:47 PM, Borislav Petkov wrote:
> On Fri, May 31, 2024 at 10:00:15AM +0530, Nikunj A Dadhania wrote:
>> The sev-guest driver encryption code uses Crypto API for SNP guest
>> messaging to interact with AMD Security processor. For enabling SecureTSC,
>> SEV-SNP guests need to send a TSC_INFO request guest message before the
>> smpboot phase starts. Details from the TSC_INFO response will be used to
>> program the VMSA before the secondary CPUs are brought up. The Crypto API
>> is not available this early in the boot phase.
>>
>> In preparation of moving the encryption code out of sev-guest driver to
>> support SecureTSC and make reviewing the diff easier, start using AES GCM
>> library implementation instead of Crypto API.
>>
>> Drop __enc_payload() and dec_payload() helpers as both are pretty small and
>> can be moved to the respective callers.
>
> Please use this streamlined commit message for your next submission:
>
> "The sev-guest driver encryption code uses the crypto API for SNP guest messaging
> with the AMD Security processor. In order to enable secure TSC, SEV-SNP guests
> need to send such a TSC_INFO message before the APs are booted. Details from the
> TSC_INFO response will then be used to program the VMSA before the APs are
> brought up.
>
> However, the crypto API is not available this early in the boot process.
>
> In preparation for moving the encryption code out of sev-guest to support secure
> TSC and to ease review, switch to using the AES GCM library implementation
> instead.
>
> Drop __enc_payload() and dec_payload() helpers as both are small and can be
> moved to the respective callers."
>

Sure

Regards
Nikunj