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Date: Thu, 20 Jun 2013 19:10:15 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Borislav Petkov <bp@alien8.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>,
        Ingo Molnar <mingo@kernel.org>, Linux EFI <linux-efi@vger.kernel.org>,
        Matt Fleming <matt@console-pimps.org>, X86 ML <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, Borislav Petkov <bp@suse.de>
Subject: Re: [PATCH -v2 0/4] EFI 1:1 mapping
Message-ID: <20130620181015.GA27833@srcf.ucam.org>
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On Thu, Jun 20, 2013 at 08:08:08PM +0200, Borislav Petkov wrote:
> On Thu, Jun 20, 2013 at 06:12:10PM +0100, Matthew Garrett wrote:
> > On Thu, Jun 20, 2013 at 07:01:24PM +0200, Borislav Petkov wrote:
> > 
> > > If we can detect the Macs, we can make this decision automatic. And
> > > since no Mac boots windoze, a single DMI check of the sort "if (Mac)"
> > > should suffice.
> > 
> > Yes, we can special-case Macs. But since our behaviour is then obviously 
> > different to Windows, we'll inevitably break some other system.
> 
> Why different? We'll have the high mappings and shove the 1:1 mappings
> down SetVirtualAddressMap by default.

Because Windows passes high addresses to SetVirtualAddressMap(), and 
because if you can imagine firmware developers getting it wrong then 
firmware developers will have got it wrong.

-- 
Matthew Garrett | mjg59@srcf.ucam.org
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