Re: [PATCH Part1 RFC v3 20/22] x86/boot: Add Confidential Computing address to setup_header

Borislav Petkov
2021-06-24T12:55:01Z

On Thu, Jun 24, 2021 at 07:34:47AM -0500, Michael Roth wrote:
> Well, that's sufficient for the boot/compressed->uncompressed parameter
> passing, but wouldn't actual bootloaders still need something in
> setup_data/setup_header to pass in the CC blob (for things like non-EFI
> environments/containers)? I was under the impression that using
> boot_params directly was more of a legacy/ad-hoc thing, is that
> accurate?

/me goes and rereads your early mail.

I'm more confused.

You're talking about parsing an EFI table early which contains the
ccblob and in it is the CPUID page.

Now above you say, "non-EFI environments".

I'm guessing you want to support both so you want to either parse an EFI
table on EFI environments or pass the blob in a different way in non-EFI
envs. Yes, no?

Also, you want to pass the previously parsed CPUID page address to
kernel proper. For that I suggested to use boot_params.

What else?

How about you explain in a lot more detail what exactly the requirements
and the use cases are so that we can have a common base to discuss it
on.

Thx.

--
Regards/Gruss,
Boris.