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Subject: Re: [RFC, PATCH 18/22] x86/mm: Handle allocation of encrypted pages
To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Tom Lendacky <thomas.lendacky@amd.com>
References: <20180305162610.37510-1-kirill.shutemov@linux.intel.com>
 <20180305162610.37510-19-kirill.shutemov@linux.intel.com>
Cc:     Kai Huang <kai.huang@linux.intel.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
From:   Dave Hansen <dave.hansen@intel.com>
Message-ID: <6551765a-5926-8445-d867-8f7c6bf343b4@intel.com>
Date:   Mon, 5 Mar 2018 11:07:55 -0800
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On 03/05/2018 08:26 AM, Kirill A. Shutemov wrote:
> kmap_atomic_keyid() would map the page with the specified KeyID.
> For now it's dummy implementation that would be replaced later.

I think you need to explain the tradeoffs here.  We could just change
the linear map around, but you don't.  Why?