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Date: Wed, 16 Jun 2021 15:02:34 +0200
From: Borislav Petkov <bp@alien8.de>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org,
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Subject: Re: [PATCH Part1 RFC v3 11/22] x86/sev: Add helper for validating
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In-Reply-To: <9f012bcb-4756-600d-6fe8-b1db9b972f17@amd.com>

On Wed, Jun 16, 2021 at 07:49:25AM -0500, Brijesh Singh wrote:
> If you still think ...

I think you should answer my question first:

> Imagine you're a guest owner and you haven't written the SNP code and
> you don't know how it works.
>
> You start a guest in the public cloud and it fails because the
> hypervisor violates the GHCB protocol and all that guest prints before
> it dies is
>
> "general request termination"
>
> How are you - the guest owner - going to find out what exactly happened?
>
> Call support?

And let me paraphrase it again: if the error condition with which the
guest terminates is not uniquely identifiable but simply a "general
request", how are such conditions going to be debugged?

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette