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Message-ID: <8647895b-560f-2272-aae4-eda00fc06eca@zhaoxin.com>
Date:   Mon, 17 Apr 2023 10:47:52 +0800
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Subject: Re: [PATCH] x86/cpufeatures: extend CPUID leaf 0xc0000001 support for
 Zhaoxin
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To:     Borislav Petkov <bp@alien8.de>
CC:     <tglx@linutronix.de>, <mingo@redhat.com>,
        <dave.hansen@linux.intel.com>, <hpa@zytor.com>, <x86@kernel.org>,
        <linux-kernel@vger.kernel.org>, <peterz@infradead.org>,
        <seanjc@google.com>, <pbonzini@redhat.com>, <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>
References: <20230414095334.8743-1-TonyWWang-oc@zhaoxin.com>
 <20230414104808.GBZDkvaJechZSM+SI9@fat_crate.local>
 <7866e99a-df88-14fa-92ae-c5b5d176724b@zhaoxin.com>
 <20230414134824.GCZDlZqDWLl6A958SF@fat_crate.local>
From:   Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
In-Reply-To: <20230414134824.GCZDlZqDWLl6A958SF@fat_crate.local>
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On 4/14/23 21:48, Borislav Petkov wrote:
> 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.
> 

Ok, will patch this tool for Zhaoxin extended CPUID leaf.
Will add Zhaoxin CPU features to kernel when they are used by the kernel.

Sincerely
TonyWWangoc