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Date:   Thu, 19 Jan 2023 10:26:42 -0600
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Subject: Re: [PATCH RFC v7 14/64] x86/sev: Add the host SEV-SNP initialization
 support
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To:     Sabin Rapan <sabrapan@amazon.com>,
        Michael Roth <michael.roth@amd.com>, kvm@vger.kernel.org
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        Brijesh Singh <brijesh.singh@amd.com>
References: <20221214194056.161492-1-michael.roth@amd.com>
 <20221214194056.161492-15-michael.roth@amd.com>
 <65f056ed-68ab-2541-7c83-3f1712e597ce@amazon.com>
From:   "Kalra, Ashish" <ashish.kalra@amd.com>
In-Reply-To: <65f056ed-68ab-2541-7c83-3f1712e597ce@amazon.com>
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On 1/11/2023 8:50 AM, Sabin Rapan wrote:
> 
> 
> On 14.12.2022 21:40, Michael Roth wrote:
>> +#ifdef CONFIG_AMD_MEM_ENCRYPT
>> +# define DISABLE_SEV_SNP       0
>> +#else
>> +# define DISABLE_SEV_SNP       (1 << (X86_FEATURE_SEV_SNP & 31))
>> +#endif
>> +
> 
> Would it make sense to split the SEV-* feature family into their own
> config flag(s) ?
> I'm thinking in the context of SEV-SNP running on systems with
> Transparent SME enabled in the bios. In this case, enabling
> CONFIG_AMD_MEM_ENCRYPT will also enable SME in the kernel, which is a
> bit strange and not necessarily useful.
> Commit 4e2c87949f2b ("crypto: ccp - When TSME and SME both detected
> notify user") highlights it.
> 

Yes, we plan to move the SNP host initialization stuff into a separate 
source file and under a different config flag such as CONFIG_KVM_AMD_SEV
or something.

Thanks,
Ashish