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] SMP on the MacBook

To: "Marco Gerards" <mgerards@xxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: RE: [Xen-devel] SMP on the MacBook
From: "Ian Pratt" <m+Ian.Pratt@xxxxxxxxxxxx>
Date: Wed, 9 Aug 2006 21:05:43 +0100
Delivery-date: Wed, 09 Aug 2006 13:06:22 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
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: Aca74rFnpXmEyVGXSli/BvS9MvKddQADCsCA
Thread-topic: [Xen-devel] SMP on the MacBook
> Xen (testing) works perfectly for me when starting it with "nosmp",
> however when not using it, it crashes while starting up the second
> core.  There have been some bug report on this issue already.

Marco,
Have you tried -unstable? Some potentially relevant files have been
updated.

Also, exactly which version of Linux boots OK? Does 2.6.16 e.g. from the
DemoCD?

Thanks,
Ian

 
> Below I will explain the problem in more detail and with some
> observations.  I will be very grateful if someone can come up with
> ideas of how to fix this or give me some ideas that can lead to a
> solution.  Not only Xen has this problem, but so has FreeBSD and
> NetBSD, so a solution will be beneficial to these projects as well.
> 
> What happens is the following: The first core sends two IPI
> messages(INIT and STARTUP) to start the second core.  When the second
> core is started, it notifies the first core of this so it can continue
> with the boot process.  However, the second core is not started by
> these messages, the loop that waits for the second core times out,
> continues and Xen crashes.
> 
> One strange thing is that Xen initializes the second core properly
> when you press a key on the keyboard after the IPIs are sent.  I am
> expecting this interrupt somehow wakes up the second core so it can
> accept and process the IPIs.  Because it is a laptop the second core
> is put in deep sleep mode to save power in case an OS does not use
> this core at all.  But as I understand it, it should wake up when an
> INIT IPI arrives.
> 
> The problems I am having with Xen can be reproduced with linux when
> booting with "acpi=ht", which means the ACPI interpreter is not
> started.
> 
> Hopefully someone has some ideas how to deal with this issue and how
> to properly fix this.  If you want more information or want me to test
> things, feel free to ask.
> 
> Thanks,
> Marco
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel

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