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Date:   Fri, 19 Jun 2020 18:40:56 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Richard Hughes <hughsient@gmail.com>
Cc:     Borislav Petkov <bp@alien8.de>,
        Daniel Gutson <daniel@eclypsium.com>,
        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>,
        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 <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Ability to read the MKTME status from userspace
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On Fri, Jun 19, 2020 at 05:33:39PM +0100, Richard Hughes wrote:
> On Fri, 19 Jun 2020 at 17:10, Borislav Petkov <bp@alien8.de> wrote:
> > - do you just want to display feature support?
> 
> Yes. I want to show the user *why* TME is not available.

So even if it is "available" that's fine, even if it is not being used?

And how can you ever tell if a BIOS disables a CPU feature, yet the chip
still has it?  That should be not seen from the OS as it really doesn't
care, it just knows if the feature is able to be used or not.

thanks,

greg k-h