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Date:   Fri, 17 Jan 2020 19:47:20 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
        x86@kernel.org, linux-kernel@vger.kernel.org,
        DavidWang@zhaoxin.com, CooperYan@zhaoxin.com,
        QiyuanWang@zhaoxin.com, HerryYang@zhaoxin.com
Subject: Re: [PATCH] x86/cpu: remove redundant cpu_detect_cache_sizes
Message-ID: <20200117184720.GB31472@zn.tnic>
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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.

https://people.kernel.org/tglx/notes-about-netiquette