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Date: Wed, 3 Oct 2012 06:28:03 +0100
From: Matthew Garrett <mjg@redhat.com>
To: Thavatchai Makphaibulchoke <thavatchai.makpahibulchoke@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>, T Makphaibulchoke <tmac@hp.com>,
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Subject: Re: [PATCH] Fix devmem_is_allowed for below 1MB accesses for an
 efi machine
Message-ID: <20121003052803.GA27464@srcf.ucam.org>
References: <1349213536-3436-1-git-send-email-tmac@hp.com>
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On Tue, Oct 02, 2012 at 11:13:17PM -0600, Thavatchai Makphaibulchoke wrote:

> Sounds like a better solution is to allow accesses to only I/O regions 
> presented in the EFI memory map for physical addresses below 1 MB.

That won't work - unfortunately we do still need the low region to be 
available for X because some platforms expect us to use int10 even on 
EFI (yes, yes, I know). Do you have a copy of the EFI memory map for a 
system that's broken with the current code?

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