On Thu, Jun 24, 2021 at 09:27:41AM +0200, Borislav Petkov wrote:

On Wed, Jun 23, 2021 at 10:19:11PM -0500, Michael Roth wrote:

quoted

One downside to this is we still need something in the boot protocol,
either via setup_data, or setup_header directly.

Huh, now I'm confused. You gave the acpi_rsdp_addr example and I thought
that should be enough, that's why I suggested boot_params.

Well, that's enough for the boot/compressed->uncompressed parameter
passing, but would a bootloader be allowed to use that same approach to
pass in the CC blob (for things like non-EFI/containers)? I was under the
impression that for that case we'd still want something in
setup_header/setup_data for bootloaders to use, and that using boot_params
directly is more of a legacy/ad-hoc thing. Is that accurate?

Maybe you should point me to the code which does what you need so that I
can get a better idea...

quoted

Having it in setup_header avoids the need to also have to add a field
to boot_params for the boot/compressed->uncompressed passing, but
maybe that's not a good enough justification. Perhaps if the TDX folks
have similar needs though.

Yes, reportedly they do so I guess the solution should be
vendor-agnostic. Let's see what they need first.

Ok, good to know.

Thx.

-- 
Regards/Gruss,
    Boris.

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