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Date:   Wed, 20 Jul 2022 07:44:30 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Marc Orr <marcorr@google.com>
Cc:     Dave Hansen <dave.hansen@intel.com>,
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Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted
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On Tue, Jul 19, 2022 at 05:26:21PM -0700, Marc Orr wrote:
> These feature tags are a mess to keep track of.

Well, looking at those tags, it doesn't look like you'll stop using them
anytime soon.

And once all the required SNP/TDX features are part of the guest image,
- including unaccepted memory - if anything, you'll have less tags.

:-)

> - Do we anticipate (many) more features for confidential compute in
> the future that require code in both the guest FW and guest kernel? If
> yes, then designing a FW-kernel feature negotiation could be useful
> beyond this situation.

Good question.

> - Dave's suggestion to "2. Boot some intermediate thing like a
> bootloader that does acceptance ..." is pretty clever! So if upstream
> thinks this FW-kernel negotiation is not a good direction, maybe we
> (Google) can pursue this idea to avoid introducing yet another tag on
> our images.

Are those tags really that nasty so that you guys are looking at
upstream changes just to avoid them?

Thx.

-- 
Regards/Gruss,
    Boris.

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