From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <aliguori@us.ibm.com>
Subject: Re: Regarding page table management changes from Xen
	v1to	Xen v2 (and v3)
Date: Wed, 26 Apr 2006 18:33:18 -0500
Message-ID: <4450033E.7070505@us.ibm.com>
References: <A95E2296287EAD4EB592B5DEEFCE0E9D4BA489@liverpoolst.ad.cl.cam.ac.uk>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <A95E2296287EAD4EB592B5DEEFCE0E9D4BA489@liverpoolst.ad.cl.cam.ac.uk>
List-Unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: Ian Pratt <m+Ian.Pratt@cl.cam.ac.uk>
Cc: xen-devel@lists.xensource.com, Himanshu Raj <rhim@cc.gatech.edu>
List-Id: xen-devel@lists.xenproject.org

Ian Pratt wrote:
>>> On 64b we could use the 1:1 mapping of all physmem that Xen has. 
>>> Obviously that is infeasible on 32b. In fact the interface 
>>>       
>> (passing a 
>>     
>>> virtual address) pretty much means we have to use a linear 
>>>       
>> mapping in 
>>     
>>> both cases.
>>>       
>> Couldn't we temporarily map the page table page?  Not that we 
>> would actually want to do that.  Just trying to confirm my understand.
>>     
>
> Sure, but that's expensive on 32b as map_domain_mem has to do real work
> (it's cheap on 64b as we have a 1-to-1 map of machine memory).
>   

Excellent, that's just what I thought.

Thanks Ian!

Regards,

Anthony Liguori

> Ian
>