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Date:   Fri, 27 Aug 2021 22:17:25 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Tom Lendacky <thomas.lendacky@amd.com>
Cc:     Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
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Subject: Re: [PATCH Part1 v5 33/38] x86/sev: Provide support for SNP guest
 request NAEs
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On Fri, Aug 27, 2021 at 02:57:11PM -0500, Tom Lendacky wrote:
> The main thing about this is that it is an error code from the HV on
> extended guest requests. The HV error code sits in the high-order 32-bits of
> the SW_EXIT_INFO_2 field. So defining it either way seems a bit confusing.
> To me, the value should just be 1ULL and then it should be shifted when
> assigning it to the SW_EXIT_INFO_2.

Err, that's from the GHCB spec:

"The hypervisor must validate that the guest has supplied enough pages

...

certificate data in the RBX register and set the SW_EXITINFO2 field to
0x0000000100000000."

So if you wanna do the above, you need to fix the spec first. I'd say.

:-)

-- 
Regards/Gruss,
    Boris.

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