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Subject: Re: [PATCH v15 01/26] Documentation/x86: Add CET description
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Dave.Martin@arm.com, arnd@arndb.de, bp@alien8.de,
        bsingharora@gmail.com, corbet@lwn.net, dave.hansen@linux.intel.com,
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References: <20201110162211.9207-2-yu-cheng.yu@intel.com>
 <20201130182641.29812-1-ndesaulniers@google.com>
From:   "Yu, Yu-cheng" <yu-cheng.yu@intel.com>
Message-ID: <4fad528b-e467-f96d-b7fb-9484fd975886@intel.com>
Date:   Mon, 30 Nov 2020 10:34:38 -0800
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On 11/30/2020 10:26 AM, Nick Desaulniers wrote:
> (In response to https://lore.kernel.org/lkml/20201110162211.9207-2-yu-cheng.yu@intel.com/)
> 
>> These need to be enabled to build a CET-enabled kernel, and Binutils v2.31
>> and GCC v8.1 or later are required to build a CET kernel.
> 
> What about LLVM? Surely CrOS might be of interest to ship this on (we ship the
> equivalent for aarch64 on Android).
> 

I have not built with LLVM, but think it probably will work as well.  I 
will test it.

>> An application's CET capability is marked in its ELF header and can be
>> verified from the following command output, in the NT_GNU_PROPERTY_TYPE_0
>> field:
>>
>>      readelf -n <application> | grep SHSTK
>>          properties: x86 feature: IBT, SHSTK
> 
> Same for llvm-readelf.
> 

I will add that to the document.

Thanks,
Yu-cheng