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

[Xen-devel] Re: x86_64 SMP support (status update)

To: "Nakajima, Jun" <jun.nakajima@xxxxxxxxx>
Subject: [Xen-devel] Re: x86_64 SMP support (status update)
From: Chris Wright <chrisw@xxxxxxxx>
Date: Mon, 27 Jun 2005 14:52:42 -0700
Cc: Chris Wright <chrisw@xxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Mon, 27 Jun 2005 21:51:40 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <7F740D512C7C1046AB53446D37200173046194E4@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/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>
References: <7F740D512C7C1046AB53446D37200173046194E4@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.6i
* Nakajima, Jun (jun.nakajima@xxxxxxxxx) wrote:
> Chris Wright wrote:
> > Here's an updated patch that fixes that faulting.  It uses gdt per
> > page like i386 is doing, still crashing upon schedule.  Why does each
> > gdt entry need it's own page?
> 
> Each gdt entry? I think gdt should be per vcpu, but I don't understand
> "each gdt entry". Can you please point to the code you are talking
> about?

Yes, the table is in arch/xen/x86_64/kernel/head.S (cpu_gdt_table, which
has 16 8 byte entries per cpu).  However rather than using that table directly,
we must copy the entries into a per cpu page.  Xen side has assumptions
regarding gdt being page sized (8 bytes * 512 entries, e.g. in
xen/arch/x86/mm.c in alloc_segdesc_page).  That help?

thanks,
-chris

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