From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40460) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlGK1-0004b7-8p for qemu-devel@nongnu.org; Mon, 03 Nov 2014 07:01:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XlGJs-0003Mo-5w for qemu-devel@nongnu.org; Mon, 03 Nov 2014 07:01:21 -0500 Received: from mail-la0-x22e.google.com ([2a00:1450:4010:c03::22e]:43344) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlGJr-0003MY-R7 for qemu-devel@nongnu.org; Mon, 03 Nov 2014 07:01:12 -0500 Received: by mail-la0-f46.google.com with SMTP id hs14so9218812lab.5 for ; Mon, 03 Nov 2014 04:01:08 -0800 (PST) Sender: Paolo Bonzini Message-ID: <54576E7F.3000901@redhat.com> Date: Mon, 03 Nov 2014 13:01:03 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <20140901060506.GA20186@redhat.com> <54042514.6090206@intel.com> <003AAFE53969E14CB1F09B6FD68C3CD478F16D2A@ORSMSX101.amr.corp.intel.com> <54277979.7070408@intel.com> <20140929100111.GA32459@redhat.com> <542A18BD.2060008@intel.com> <20141007072653.GB2424@redhat.com> <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> In-Reply-To: <54576B5A.50005@intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit 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: "Chen, Tiejun" , "Michael S. Tsirkin" Cc: "xen-devel@lists.xensource.com" , "qemu-devel@nongnu.org" 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