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Date: Tue, 9 Aug 2011 11:50:14 -0400
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Ian Campbell <Ian.Campbell@eu.citrix.com>
Cc: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>,
        "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>,
        Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] xen: modify kernel mappings corresponding to granted
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> > So I hadn't looked at this in detail, but I wonder if we can use the
> > MULTIcall for this? It looks like we need to do two hypercalls so why
> > not batch it?
> 
> That was going to be my next question. We should definitely batch these
> if possible.
> 
> > And while we are it - we could change the MMU ops to only do this on
> > initial domain and for the domU case do the old mechanism?
> 
> We need this in domU for driver domains and the like, don't we?

Sure, but I believe the majority of domU domains would not require this.

I was thinking that when we start playing with the device/driver domains
we would want to escalate the privilige level (or perhaps not)? Or
perhaps introcuce a new type - "if (xen_driver_domain())" to recognize
that we are special ?