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From: Kyle Huey <me@kylehuey.com>
Date: Thu, 10 Nov 2016 15:38:41 -0800
Message-ID: <CAP045Arx_8XLGkrZdj4+ZOKeWhrbVM5CUbNbiPkdWjLQC4YkUw@mail.gmail.com>
Subject: Re: [PATCH v10 6/7] x86/arch_prctl: Add ARCH_[GET|SET]_CPUID
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>,
        "Robert O'Callahan" <robert@ocallahan.org>,
        Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@redhat.com>,
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On Wed, Nov 9, 2016 at 5:34 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> On Wed, 9 Nov 2016, Borislav Petkov wrote:
>> +static void init_misc_enables(struct cpuinfo_x86 *c)
>> +{
>> +     u64 val, misc_en;
>> +
>> +     if (rdmsrl_safe(MSR_MISC_FEATURES_ENABLES, &misc_en))
>> +             return;
>> +
>> +     misc_en &= ~MSR_MISC_ENABLES_CPUID_FAULT_ENABLE;
>
> I rather prefer to write this MSR to 0 right away and just enable the bits
> which we really support.

I've gone ahead and done this.

- Kyle