From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58394) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlHP4-0006wa-Jr for qemu-devel@nongnu.org; Mon, 03 Nov 2014 08:10:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XlHOy-0000wI-FV for qemu-devel@nongnu.org; Mon, 03 Nov 2014 08:10:38 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40854) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlHOy-0000wD-6h for qemu-devel@nongnu.org; Mon, 03 Nov 2014 08:10:32 -0500 Date: Mon, 3 Nov 2014 15:10:22 +0200 From: "Michael S. Tsirkin" Message-ID: <20141103131022.GB16423@redhat.com> References: <543622CC.6050807@intel.com> <20141012095021.GC9567@redhat.com> <544A0174.7000003@intel.com> <20141024134747.GA6024@redhat.com> <5451ED1E.1000300@intel.com> <5457335B.1000308@intel.com> <5457686E.7020601@redhat.com> <545768CC.3000903@intel.com> <54576B5A.50005@intel.com> <54576E7F.3000901@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54576E7F.3000901@redhat.com> Subject: Re: [Qemu-devel] [Xen-devel] [PATCH 2/2] xen:i386:pc_piix: create isa bridge specific to IGD passthrough List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: "Chen, Tiejun" , "xen-devel@lists.xensource.com" , "qemu-devel@nongnu.org" On Mon, Nov 03, 2014 at 01:01:03PM +0100, Paolo Bonzini wrote: > > > On 03/11/2014 12:47, Chen, Tiejun wrote: > > On 2014/11/3 19:36, Chen, Tiejun wrote: > >> On 2014/11/3 19:35, Paolo Bonzini wrote: > >>> On 03/11/2014 08:48, Chen, Tiejun wrote: > >>>>>>>> I think the point was mostly to reserve 1f to prevent > >>>>>>>> devices from using it. > >>>>>>>> As we populate slots in order it doesn't seem to important ... > >>>>>>> > >>>>>>> If we populate slot at !1f GFX driver can't find this ISA bridge. > >>>>>> > >>>>>> Right, but I mean if no special options are used, 1f will typically > >>>>>> stay free without any effort on our side. > >>>>> > >>>>> Yeah. > >>>>> > >>>>> Actually based on current info we know, seems 1f is just specific to > >>>>> our > >>>>> scenario :) So I always think we can occupy that. But Paolo and you > >>>>> can > >>>>> really determine this point. > >>>> > >>>> What's your idea? > >>> > >>> I do not have any objection to always occupying 1f for Xen IGD > >>> passthrough. > > > > After I go back to look at this again, I hope you don't misunderstand > > what Michael mean now. He was saying we don't need to create a new > > separate machine specific to IGD passthrough. But that idea is just from > > you :) > > It's difficult for me to follow, because xen_igd_passthrough_pc_hvm_init > does not exist in the current tree. > > The patches seem good to me; I was assuming that the new machine type > would call xen_igd_passthrough_pc_hvm_init, but apparently I'm wrong? > Paolo Discussed on irc, Paolo said so i don't really care how the ISA bridge is created -- MST