WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

RE: [Xen-devel] [PATCH][VT]vga acceleration for cirrus logic device mode

To: "Keir Fraser" <Keir.Fraser@xxxxxxxxxxxx>
Subject: RE: [Xen-devel] [PATCH][VT]vga acceleration for cirrus logic device model
From: "Jiang, Yunhong" <yunhong.jiang@xxxxxxxxx>
Date: Fri, 23 Sep 2005 20:51:22 +0800
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Fri, 23 Sep 2005 12:49:29 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcXAOcicYd2N/AV3QEel7ILBEWhgzgAAU11g
Thread-topic: [Xen-devel] [PATCH][VT]vga acceleration for cirrus logic device model
Keir Fraser wrote:
>>> allocate new l2 tables on demand.
>>> 
>>> Something like this will certainly be needed for 64-bit tables
>>> anyway, where it's infeasible to pre-allocate all l3 and l2 table
>>> entries. 
>> 
>> I'm a bit confused on this. This mapping is for 1:1 page table, and
>> there is only one L3 table and 4 l2 table totally even for 64 bit
>> table.
> 
> Ah yes, good point.
> 
> In that case I think the code's fine as it is. I'll check it in.
> 
>   -- Keir

Hmm, seems you have been persuaded by me, but I can't persuade myself
after more thinking :-) 

In fact, I'm not quite sure still and hope your feedback.

There may be some problem on current 1:1 page table for 64 bit guest.
Considering a guest has memory more than 4G. Current implementation may
cause problem on physical to machine mapping.

However, this patch works on currently 1:1 page table implementation. So
how about check it in firstly, and I will provide a total solution to
improve the whole thing, because I think the 4 level 1:1 page table is
more complex than 3 level, we may have to provide dynamical setting,
still on consideration.

Thanks
Yunhong Jiang

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel