From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@linux.intel.com>
Subject: Re: [PATCH 1/3] x86: calculate precisely the memory needed by init_memory_mapping
Date: Mon, 20 Jun 2011 15:37:33 -0700
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On 06/07/2011 11:13 AM, stefano.stabellini@eu.citrix.com wrote:
> 
> - remove the extra page added on x86_32 for the fixmap because is not
> needed: the PMD entry is already allocated and contiguous for the whole
> range (a PMD page covers 4G of virtual addresses) and the pte entry is
> already allocated by early_ioremap_init.
> 

Hi Stefano,

I think this is wrong.  A PMD page covers *1G* of virtual addresses, and
in the 2+2 and 1+3 memory configurations, we may or may not need a
separate PMD for the fixmap.

Am I missing something?

	-hpa