Re: [PATCH v33 01/21] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits

From: Jarkko Sakkinen
Date: Wed Jun 24 2020 - 21:25:54 EST


On Mon, Jun 22, 2020 at 07:37:11PM +0200, Borislav Petkov wrote:
> On Thu, Jun 18, 2020 at 01:08:23AM +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].
> >
> > Add IA32_FEATURE_CONTROL_SGX_ENABLE. BIOS can use this bit to opt-in SGX
>
> I'm guessing that wants to be
>
> IA32_FEATURE_CONTROL.SGX_ENABLE
>
> judging by the diff and the SDM chapter.

Underscore must be just a typo.

>
> > before locking the feature control MSR [2].
> >
> > [1] Intel SDM: 36.7.2 Intel® SGX Resource Enumeration Leaves
> > [2] Intel SDM: 36.7.1 Intel® SGX Opt-In Configuration
> >
> > Cc: Borislav Petkov <bp@xxxxxxxxx>
> > Acked-by: Jethro Beekman <jethro@xxxxxxxxxxxx>
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> > Co-developed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > ---
> > arch/x86/include/asm/cpufeature.h | 5 +++--
> > arch/x86/include/asm/cpufeatures.h | 7 ++++++-
> > arch/x86/include/asm/disabled-features.h | 18 +++++++++++++++---
> > arch/x86/include/asm/msr-index.h | 1 +
> > arch/x86/include/asm/required-features.h | 2 +-
> > arch/x86/kernel/cpu/common.c | 4 ++++
> > tools/arch/x86/include/asm/cpufeatures.h | 7 ++++++-
>
> Also, please drop this change to tools/, see
>
> https://lkml.kernel.org/r/20200622141737.GA30611@xxxxxxxxxx
>
> from today.

OK I reverted it [*].

> With those addressed:
>
> Reviewed-by: Borislav Petkov <bp@xxxxxxx>

Thank you, I'll update this to the commit.

>
> Thx.
>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette

[*] By "git diff -R HEAD~1 -- tools/arch/x86/include/asm/cpufeatures.h | patch -p1".

/Jarkko