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Date: Mon, 12 Sep 2016 19:18:28 +0200
From: Borislav Petkov <bp@suse.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Kyle Huey <me@kylehuey.com>, Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [PATCH] prctl,x86 Add PR_[GET|SET]_CPUID for controlling the
 CPUID instruction.
Message-ID: <20160912171828.gztxu5bgbmjcd4mt@pd.tnic>
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On Mon, Sep 12, 2016 at 09:56:11AM -0700, Andy Lutomirski wrote:
> This should have a cpufeature bit and show up in /proc/cpuinfo.  That

Haha, test a cpufeature with a faulting CPUID :-)

Yeah, we need a synthetic flag and query MSR_PLATFORM_INFO[31] which
denotes whether the other MSR - MISC_FEATURES_ENABLES - is there and bit
0 is defined.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--