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Date: Fri, 07 Sep 2012 08:40:59 +0100
From: "Jan Beulich" <JBeulich@suse.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Vasco Dias" <rafa.vasco@gmail.com>,
        "Matt Fleming" <matt.fleming@intel.com>,
        "Matthew Garrett" <mjg@redhat.com>, <linux-efi@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <cJ-ko@zougloub.eu>
Subject: Re: [PATCH] x86, efi: 1:1 pagetable mapping for virtual EFI
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>>> On 06.09.12 at 19:07, "H. Peter Anvin" <hpa@zytor.com> wrote:
> Anyone care to refresh my memory why we can't use the "global" 
> 1:1+kernel map, possibly with some improvements (which would benefit the 
> users of those maps too)?  With that I mean initial_page_map on i386 and 
> trampoline_pgd on x86-64...

I don't think you want anything inserted in the low part of those
(kernel-only) page tables, not even transiently.

Jan