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Date:   Fri, 14 Apr 2023 15:48:24 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com,
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        kim.phillips@amd.com, babu.moger@amd.com,
        pawan.kumar.gupta@linux.intel.com, sandipan.das@amd.com,
        CobeChen@zhaoxin.com, TimGuo@zhaoxin.com, LeoLiu-oc@zhaoxin.com
Subject: Re: [PATCH] x86/cpufeatures: extend CPUID leaf 0xc0000001 support
 for Zhaoxin
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On Fri, Apr 14, 2023 at 09:14:17PM +0800, Tony W Wang-oc wrote:
>  The instructions about these flags can be executed at any privilege
> level. I think using these flags in kernel mode is a case. This patch
> shows the statement of these flags to the user mode explicitly. So users
> can see and use these CPU features conveniently.
> 
> > If you want to dump them on the hardware to know what's set or not,
> > there's tools/arch/x86/kcpuid/ for that.

See this here. We have this tool exactly for users who wanna see CPU
features. All CPU features, as a matter of fact.

-- 
Regards/Gruss,
    Boris.

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