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] question about patch 13252

To: "Lu, Guanqun" <guanqun.lu@xxxxxxxxx>, "jbeulich@xxxxxxxxxx" <jbeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] question about patch 13252
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Thu, 19 Mar 2009 14:49:55 +0000
Cc: xen-devel组 <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Thu, 19 Mar 2009 07:50:09 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <8FED46E8A9CA574792FC7AACAC38FE7701CB8168B7@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
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/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcmonBcxnNUdkO56SQePfluoz/7mKQAAhEIOAAAtsIAAAMYYVw==
Thread-topic: [Xen-devel] question about patch 13252
User-agent: Microsoft-Entourage/12.15.0.081119
On 19/03/2009 14:34, "Lu, Guanqun" <guanqun.lu@xxxxxxxxx> wrote:

> Thanks for your reply.
> 
> It makes a little sense...
> But the problem is that when we do S3,
> we execute load_TR() again (in file arch/x86/acpi/suspend.c),
> and this causes the bug.
> 
> Do we need to go back to non-compat gdt_table when it resumes, and
> switch to compat_gdt_table again?

Ah, I see. There are a few options, the easiest of which is to leave the B
bit clear in both descriptors. I'm not certain whether that actually matters
for any reason, but I think for our purposes it does not.

If Jan can counter my claim, then you can instead switch back to the
non-compat GDT for the LTR, or you can decide which descriptor to set B in
based on which GDT you're running on, or force the B bit in both descriptors
after the LTR, or... You have a few options. :-)

 -- Keir



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