Re: [PATCH] x86/cpu: remove redundant cpu_detect_cache_sizes

From: Borislav Petkov
Date: Fri Jan 17 2020 - 13:47:34 EST


On Wed, Jan 15, 2020 at 04:00:57PM +0800, Tony W Wang-oc wrote:
> Before call cpu_detect_cache_sizes get l2size from CPUID.80000006,
> these CPUs have called init_intel_cacheinfo get l2size/l3size from
> CPUID.4.

Questions:

* Does CPUID(4) give the same result as CPUID(80000006) on those CPUs?

* cpu_detect_cache_sizes() sets c->x86_tlbsize while
init_intel_cacheinfo() would set it only when it calls the former
function - cpu_detect_cache_sizes() - at the end:

if (!l2)
cpu_detect_cache_sizes(c);

Does that happen on those CPUs?

--
Regards/Gruss,
Boris.

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