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Subject: Re: [PATCH v5 31/32] x86: Add sysfs support for Secure Memory
 Encryption
To: Tom Lendacky <thomas.lendacky@amd.com>, linux-arch@vger.kernel.org,
        linux-efi@vger.kernel.org, kvm@vger.kernel.org,
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References: <20170418211612.10190.82788.stgit@tlendack-t1.amdoffice.net>
 <20170418212212.10190.73484.stgit@tlendack-t1.amdoffice.net>
Cc: Rik van Riel <riel@redhat.com>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
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        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
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        Larry Woodman <lwoodman@redhat.com>,
        Brijesh Singh <brijesh.singh@amd.com>, Ingo Molnar <mingo@redhat.com>,
        Borislav Petkov <bp@alien8.de>, Andy Lutomirski <luto@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Alexander Potapenko <glider@google.com>,
        Dave Young <dyoung@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
        Dmitry Vyukov <dvyukov@google.com>
From: Dave Hansen <dave.hansen@intel.com>
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Date: Fri, 21 Apr 2017 14:55:13 -0700
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On 04/18/2017 02:22 PM, Tom Lendacky wrote:
> Add sysfs support for SME so that user-space utilities (kdump, etc.) can
> determine if SME is active.
> 
> A new directory will be created:
>   /sys/kernel/mm/sme/
> 
> And two entries within the new directory:
>   /sys/kernel/mm/sme/active
>   /sys/kernel/mm/sme/encryption_mask

Why do they care, and what will they be doing with this information?