From mboxrd@z Thu Jan  1 00:00:00 1970
From: "James Harper" <james.harper@bendigoit.com.au>
Subject: Re: [Xen-devel] Ideas for PV on SeaBIOS
Date: Mon, 23 May 2011 20:20:32 +1000
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> 
> On Sat, 2011-05-21 at 09:44 +0100, James Harper wrote:
> > Am I understanding right that the OS would need to be completely put on
> > hold in the middle of the hypercall while the BIOS took over and did
> > it's shutdown sequence, which presumably involves xenstore activity?
> 
> Correct, or at least that is one suggestion (probably the front runner
> at the moment).
> 
> In theory it's no worse than SMM, which Windows presumably already copes
> with, but perhaps the latency from having to do the xenstore interaction
> is far greater than any real SMM operation.
> 

How hard would it be to create a better mechanism for going forward and implement the above as a fallback if the DomU doesn't support the new mechanism?

James