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Date: Fri, 23 Feb 2024 14:23:31 -0600
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Subject: Re: [PATCH 00/11] Provide SEV-SNP support for running under an SVSM
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To: "Reshetova, Elena" <elena.reshetova@intel.com>,
 "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
 "x86@kernel.org" <x86@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
 Borislav Petkov <bp@alien8.de>, Dave Hansen <dave.hansen@linux.intel.com>,
 "H. Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>,
 Peter Zijlstra <peterz@infradead.org>,
 "Williams, Dan J" <dan.j.williams@intel.com>,
 Michael Roth <michael.roth@amd.com>, Ashish Kalra <ashish.kalra@amd.com>,
 "Shutemov, Kirill" <kirill.shutemov@intel.com>,
 "Dong, Eddie" <eddie.dong@intel.com>,
 Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
References: <cover.1706307364.git.thomas.lendacky@amd.com>
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From: Tom Lendacky <thomas.lendacky@amd.com>
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On 2/19/24 11:54, Reshetova, Elena wrote:
>> Subject: Re: [PATCH 00/11] Provide SEV-SNP support for running under an SVSM
>>
>> On 2/12/24 04:40, Reshetova, Elena wrote:
>>>> This series adds SEV-SNP support for running Linux under an Secure VM

> 
> Sorry for my ignorance, what the HV?

HV == Hypervisor

> 
>>

> 
> Kirill already commented on this, and the answer is of course we can, but imo we
> need to see a bigger picture first. If we go with option 2 above, then coming with a
> joint protocol is only limitedly useful because likely we wont be able to share the
> code in the guest kernel. Ideally I think we want a common concept and a common
> protocol that we can share in both guest kernel and coconut-svsm.
> 
> Btw, is continuing discussion here the best/preferred/efficient way forward? Or should we
> setup a call with anyone who is interested in the topic to form a joint understanding
> on what can be done here?

I'm not sure what the best way forward is since I'm not sure what a common 
concept / common protocol would look like. If you feel we can effectively 
describe it via email, then we should continue that, maybe on a new thread 
under linux-coco. If not, then a call might be best.

Thanks,
Tom

> 
> Best Regards,
> Elena.
> 
> 
>>
>> Thanks,
>> Tom
>>
>>>
>>> 5. Anything else is missing?
>>>
>>> References:
>>>
>>> [1] https://lkml.org/lkml/2023/11/22/1089
>>>
>>> [2] MSFT hyper-v implementation of AMD SEV-SNP !VMPL0 guest and TDX L2
>>> partitioning guest:
>>> https://elixir.bootlin.com/linux/latest/source/arch/x86/hyperv/ivm.c#L575
>>>
>>> [3] https://github.com/coconut-svsm/svsm
>>>
>>> [4] https://www.amd.com/content/dam/amd/en/documents/epyc-technical-
>> docs/specifications/58019.pdf
>>>
>>>