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Date: Mon, 05 Mar 2012 23:00:07 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Yinghai Lu <yinghai@kernel.org>
CC: zhenzhong.duan@oracle.com, Takashi Iwai <tiwai@suse.de>,
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Subject: Re: [PATCH] Initialize max_pfn_mapped as initial ident mapping size
 for x86_64
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On 03/05/2012 10:27 PM, Yinghai Lu wrote:
> 
>>
>> The early mapping range we can fix, and probably should.  Mapping the
>> first 4 GiB is not a lot of memory and makes a much more sensible
>> starting point.
> 
> do you mean map the 4G in head_64.S?
> 

Yes.  It would be better to design the mapping system so that it would
incrementally map everything we need (with page tables allocated out of
the memory already mapped), but that isn't a trivial exercise,
especially with the need to avoid the initramfs, kernel image and
command line and other data elements.

	-hpa


-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.