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Date:   Wed, 26 Apr 2023 15:15:26 -0500
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Subject: Re: [PATCH] docs: security: Confidential computing intro and threat
 model
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To:     Sean Christopherson <seanjc@google.com>
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References: <20230327141816.2648615-1-carlos.bilbao@amd.com>
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From:   Carlos Bilbao <carlos.bilbao@amd.com>
In-Reply-To: <ZEmBULXp24oMxaUH@google.com>
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On 4/26/23 2:53 PM, Sean Christopherson wrote:
> On Wed, Apr 26, 2023, Carlos Bilbao wrote:
>> On 4/26/23 10:51 AM, Sean Christopherson wrote:
>>> This document is named confidential-computing.rst, not tdx-and-snp.rst.  Not
>>> explicitly mentioning SEV doesn't magically warp reality to make descriptions like
>>> this one from security/secrets/coco.rst disappear:
>>>
>>>   Introduction                                                                    
>>>   ============                                                                    
>>>                                                                                 
>>>   Confidential Computing (coco) hardware such as AMD SEV (Secure Encrypted        
>>>   Virtualization) allows guest owners to inject secrets into the VMs              
>>>   memory without the host/hypervisor being able to read them.
>>>
>>> My complaint about this document being too Intel/AMD centric isn't that it doesn't
>>> mention other implementations, it's that the doc describes CoCo purely from the
>>> narrow viewpoint of Intel TDX and AMD SNP, and to be blunt, reads like a press
>>> release and not an objective overview of CoCo.
>>
>> Be specific about the parts of the document that you feel are too
>> AMD/Intel centric, and we will correct them.
> 
> The whole thing?  There aren't specific parts that are too SNP/TDX centric, the
> entire tone and approach of the document is wrong.  As I responded to Dave, I
> would feel differently if the document were named tdx-and-snp-threat-model.rst,
> but this patch proposes a generic confidential-computing.rst and presents the
> SNP+TDX confidential VM use case as if it's the *only* confidential computing use
> case.

What part of us describing the current Linux kernel threat model or
defining basic concepts of confidential computing is SNP/TDX centric?

IMHO, simply stating that "the whole thing" is wrong and that you don't
like the "tone", is not making a good enough case for us to change
anything, including the name of the document.

Thanks,
Carlos