Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

From: Kuppuswamy, Sathyanarayanan
Date: Tue Sep 28 2021 - 17:02:06 EST




On 9/28/21 1:58 PM, Borislav Petkov wrote:
On Tue, Sep 28, 2021 at 01:48:46PM -0700, Kuppuswamy, Sathyanarayanan wrote:
Just read it. If you want to use cpuid_has_tdx_guest() directly in
cc_platform_has(), then you want to rename intel_cc_platform_has() to
tdx_cc_platform_has()?

Why?

You simply do:

if (cpuid_has_tdx_guest())
intel_cc_platform_has(...);

and lemme paste from that mail: " ...you should use
cpuid_has_tdx_guest() instead but cache its result so that you don't
call CPUID each time the kernel executes cc_platform_has()."

Makes sense?

Yes. But, since the check is related to TDX, I just want to confirm whether
you are fine with naming the function as intel_*().

Since this patch is going to have dependency on TDX code, I will include
this patch in TDX patch set.



--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer