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-ia64-devel

RE: [Xen-ia64-devel] Re: [PATCH]: ptc.ga for SMP-g

To: "Isaku Yamahata" <yamahata@xxxxxxxxxxxxx>
Subject: RE: [Xen-ia64-devel] Re: [PATCH]: ptc.ga for SMP-g
From: "Xu, Anthony" <anthony.xu@xxxxxxxxx>
Date: Fri, 31 Mar 2006 10:37:01 +0800
Cc: xen-ia64-devel@xxxxxxxxxxxxxxxxxxx, Tristan Gingold <Tristan.Gingold@xxxxxxxx>
Delivery-date: Fri, 31 Mar 2006 02:38:30 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-ia64-devel-request@lists.xensource.com?subject=help>
List-id: Discussion of the ia64 port of Xen <xen-ia64-devel.lists.xensource.com>
List-post: <mailto:xen-ia64-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-ia64-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcZUBLnYj2KdAMLpRLi4OiljjzQvEQAZlKlw
Thread-topic: [Xen-ia64-devel] Re: [PATCH]: ptc.ga for SMP-g
>From: Isaku Yamahata>Sent: 2006?3?30? 22:18
>To: Xu, Anthony
>Cc: Tristan Gingold; xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
>Subject: Re: [Xen-ia64-devel] Re: [PATCH]: ptc.ga for SMP-g
>

>Page not present fault is different from tlb miss fault.
>So guest OS may handle them differently.
>For example, suppose guest OS is Linux and a area covered by dtlb
>is from PAGE_OFFSET + 64MB. In this case Linux results in kernel panic.
>
>ENTRY(page_not_present)
>  -> page_fault()
>     -> ia64_do_page_fault()
>       Here Linux searches vm area but fails.
>       then Linux tries exception table and fails.
>       then panics.
>
>It's very harmful.

In this case, you are right.

But ptc.ga has nothing to do with guest TR.
Guest Dtlb should be not overlapped with guest TR.
That means the area covered by dtlb will be not from PAGE_OFFSET + 64MB.

Thanks,
Anthony

_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel