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Date:   Fri, 19 Jun 2020 15:22:43 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Daniel Gutson <daniel@eclypsium.com>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        "David S. Miller" <davem@davemloft.net>,
        Rob Herring <robh@kernel.org>, Tony Luck <tony.luck@intel.com>,
        Rahul Tanwar <rahul.tanwar@linux.intel.com>,
        Xiaoyao Li <xiaoyao.li@intel.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        linux-kernel@vger.kernel.org, Richard Hughes <hughsient@gmail.com>
Subject: Re: [PATCH] Ability to read the MKTME status from userspace
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On Fri, Jun 19, 2020 at 10:01:36AM -0300, Daniel Gutson wrote:
> Then the user will not know that he/she could improve the security of the
> system by enabling the feature in the BIOS.

And how is the user going to know from your "module"? AFAICT, your
module loads on any system - not only on ones which have MKTME in CPUID.

> The fact that the CPU has the cap and the BIOS disables it, can
> trigger a prevention action.

I can only venture guesses what "prevention action" is - you'll have to
be more verbose here.

-- 
Regards/Gruss,
    Boris.

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