Re: [PATCH v13 01/13] x86/sev: Carve out and export SNP guest messaging init routines

From: Nikunj A. Dadhania
Date: Tue Oct 22 2024 - 00:12:48 EST


On 10/21/2024 1:18 PM, Christophe JAILLET wrote:
> Le 21/10/2024 à 07:51, Nikunj A Dadhania a écrit :
>> Currently, the SEV guest driver is the only user of SNP guest messaging.
>> All routines for initializing SNP guest messaging are implemented within
>> the SEV guest driver. To add Secure TSC guest support, these initialization
>> routines need to be available during early boot.
>>
>> Carve out common SNP guest messaging buffer allocations and message
>> initialization routines to core/sev.c and export them. These newly added
>> APIs set up the SNP message context (snp_msg_desc), which contains all the
>> necessary details for sending SNP guest messages.
>>
>> At present, the SEV guest platform data structure is used to pass the
>> secrets page physical address to SEV guest driver. Since the secrets page
>> address is locally available to the initialization routine, use the cached
>> address. Remove the unused SEV guest platform data structure.
>>
>> Signed-off-by: Nikunj A Dadhania <nikunj@xxxxxxx>
>> Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
>> ---
>
> ...
>
>> +static inline bool is_vmpck_empty(struct snp_msg_desc *mdesc)
>> +{
>> +    char zero_key[VMPCK_KEY_LEN] = {0};
>
> Nitpick: I think this could be a static const.
>

As the primary objective of this patch is to move the code, I have retained the
previous implementation.

Regards
Nikunj