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 0 of 6] Fix kexec in Xen (take 3)

To: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH 0 of 6] Fix kexec in Xen (take 3)
From: Keir Fraser <keir@xxxxxxx>
Date: Thu, 26 May 2011 10:19:59 +0100
Cc: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Thu, 26 May 2011 02:27:18 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:user-agent:date:subject:from:to:cc :message-id:thread-topic:thread-index:in-reply-to:mime-version :content-type:content-transfer-encoding; bh=IFr+8PSKu8z/lLBeWFyqv5ksRoRa7bUJ9Y9OB8HXzlM=; b=HFnX2lCUJRn3zptymTIUn6YCtcYrR2zZxyM2IYtlztWN5jVXdO/8WcTYVP1rKRdXdj 0XsOh6zb4j0J3MjfAtWZVnLupU5nO1g0//bP5ZRMX/KLftCuiecR4xQSYmXlJszc5u+R BvaKV3kvop6mJ516gcDNXW8mgmq1vh80eR/+g=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:user-agent:date:subject:from:to:cc:message-id:thread-topic :thread-index:in-reply-to:mime-version:content-type :content-transfer-encoding; b=IvMhWU/gH9VgzNe85oYOvq3wIZi72ORnDwP6fKe59eV/tcPDJLU99NUDqMpMvy0eXI qoDFw6rCx23PUuMYQPH7y10eQumv6qdHC8v7zouGB+4PVsL5IQQm+cX0biyxrnnn5H/A p3rC8vzy4wsj+iRzSbBtTAJJ07qkR91qzsmzs=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4DDE1961.80303@xxxxxxxxxx>
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: AcwbhhWrfz/LtSFHiUKeefDvO9knGw==
Thread-topic: [Xen-devel] [PATCH 0 of 6] Fix kexec in Xen (take 3)
User-agent: Microsoft-Entourage/12.29.0.110113
On 26/05/2011 10:12, "Andrew Cooper" <andrew.cooper3@xxxxxxxxxx> wrote:

>> A better reference for APIC behaviour is Chapter 10 of Volume 3A of the
>> Intel Software Developer Manual. See 10.4.7.1 particularly. The APIC is
>> software disabled on startup -- meaning that the enable bit in the SPIV
>> register is clear. That is quite different from *hardware* disable (via the
>> APICBASE MSR) which your patch attempts to deal with. In this latter case
>> the APIC would be totally shut down and it would not be possible to
>> INIT-SIPI the secondary processor. The software disable (via SPIV) is very
>> much a semi-disabled state (and disable_local_APIC() already returns an APIC
>> to that state).
>> 
>>   -- Keir
>> 
> Ok - I will read up on this more, and then I guess I have some code to
> change.

Yes, please do.

Also if you can please try to avoid making crash-specific versions of
cleanup/shutdown functions. I would actually rather have a global variable
indicating I-am-crashing-on-cpu-x, and have at that from the existing
shutdown functions to modify their behaviour.

If you can fix that plus curb your impulse to do more to the APIC code than
necessary then we have a starting point for further review.

 -- Keir



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