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Date:   Mon, 25 May 2020 10:20:13 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc:     Sean Christopherson <sean.j.christopherson@intel.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
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        haitao.huang@intel.com, andriy.shevchenko@linux.intel.com,
        tglx@linutronix.de, kai.svahn@intel.com, josh@joshtriplett.org,
        luto@kernel.org, kai.huang@intel.com, rientjes@google.com,
        cedric.xing@intel.com, puiterwijk@redhat.com,
        Jethro Beekman <jethro@fortanix.com>
Subject: Re: [PATCH v30 04/20] x86/sgx: Add SGX microarchitectural data
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On Fri, May 22, 2020 at 10:50:17PM +0300, Jarkko Sakkinen wrote:
> If other values except two are never going to be used it is more than a
> legit point to validate this field.
> 
> It also the potential to use ~0x8086 bits to be defined later if ever
> needed lets say for some kernel specific purpose.

Yah, let's cover our ass for the future. We have all seen the "this
won't be used" but then "we're using it" change of heart. IOW, let's
align with what the hw checks and we can always relax that in the future
but not the other way around.

Thx.

-- 
Regards/Gruss,
    Boris.

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