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Message-ID: <b1d00573-7234-2b72-89e1-db120395ff12@amd.com>
Date: Thu, 13 Jun 2024 09:10:44 +0530
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Subject: Re: [PATCH v9 01/24] virt: sev-guest: Use AES GCM crypto library
To: Borislav Petkov <bp@alien8.de>
Cc: linux-kernel@vger.kernel.org, thomas.lendacky@amd.com, x86@kernel.org,
 kvm@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de,
 dave.hansen@linux.intel.com, pgonda@google.com, seanjc@google.com,
 pbonzini@redhat.com
References: <20240531043038.3370793-1-nikunj@amd.com>
 <20240531043038.3370793-2-nikunj@amd.com>
 <20240612171710.GDZmnYFizmJoS5nMS1@fat_crate.local>
From: "Nikunj A. Dadhania" <nikunj@amd.com>
In-Reply-To: <20240612171710.GDZmnYFizmJoS5nMS1@fat_crate.local>
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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