Re: [PATCH v30 01/20] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits

From: Borislav Petkov
Date: Wed May 20 2020 - 08:16:33 EST


On Fri, May 15, 2020 at 03:43:51AM +0300, Jarkko Sakkinen wrote:
> From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
>
> Add X86_FEATURE_SGX from CPUID.(EAX=7, ECX=1), which informs whether the
> CPU has SGX.
>
> Add X86_FEATURE_SGX1 and X86_FEATURE_SGX2 from CPUID.(EAX=12H, ECX=0),
> which describe the level of SGX support available [1].
>
> Remap CPUID.(EAX=12H, ECX=0) bits to the Linux fake CPUID 8 in order to
> conserve some space. Keep the bit positions intact because KVM requires
> this. Reserve bits 0-7 for SGX in order to maintain this invariant also
> when new SGX specific feature bits get added.

That paragraph needs dropping now.

--
Regards/Gruss,
Boris.

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