Re: [PATCH v10 03/11] x86/cpufeatures: Add TDX Guest CPU feature

From: Borislav Petkov
Date: Thu Oct 14 2021 - 03:57:45 EST


On Wed, Oct 13, 2021 at 05:25:06PM -0700, Josh Poimboeuf wrote:
> I think Boris said that's not possible because of some ordering
> reasons which are eluding me (and I didn't have time to investigate).

The obvious one being that CPU caps aren't set yet. And then there was
this wild goose chase about fixup_pointer() and whether the compiler
generates rip-relative addressing to global vars in early boot code
which runs out of 1:1 mapping and could be loaded somewhere else...

So I'm not opposed to doing cap flags - that would get rid of the new
flags but it needs to be done carefully because with early boot, the
devil's in the detail.

Thx.

--
Regards/Gruss,
Boris.

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