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

[Borislav Petkov]

On Wed, Oct 13, 2021 at 10:44:37PM +0200, Thomas Gleixner wrote:
> No. This is tasteless garbage, really.
> 
> tdx_early_init() is invoked from x86_64_start_kernel() very early in the
> boot process __before__ is_tdx_guest() is invoked.
> 
> So why on earth is it requried to keep those conditionals and cpuid()
> muck around after init?

Yah, reportedly, they wanna parse cmdline options so it has to be after
copy_bootdata() but copy_bootdata() has a cc_platform_has() call which
ends up in is_tdx_guest() on Intel and there you have the catch 22
because CPUID hasn't happened yet in tdx_early_init().

-- 
Regards/Gruss,
    Boris.

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