From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [Qemu-devel] [PATCH 28/35] kvm: x86: Introduce kvmclock device to save/restore its state Date: Thu, 20 Jan 2011 13:42:39 -0600 Message-ID: <4D38902F.8050604@linux.vnet.ibm.com> References: <4D35BD30.1060900@siemens.com> <4D35C1CE.10509@linux.vnet.ibm.com> <4D35C648.7050809@siemens.com> <4D35C92D.7030000@linux.vnet.ibm.com> <4D36B362.70202@redhat.com> <4D371732.5040901@linux.vnet.ibm.com> <20110119171918.GI5113@redhat.com> <4D3722BB.5030407@linux.vnet.ibm.com> <4D37F5D5.3040409@redhat.com> <20110120103341.GA8675@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Gerd Hoffmann , Markus Armbruster , "kvm@vger.kernel.org" , Jan Kiszka , Glauber Costa , Marcelo Tosatti , "qemu-devel@nongnu.org" , Avi Kivity To: "Daniel P. Berrange" Return-path: Received: from e9.ny.us.ibm.com ([32.97.182.139]:46303 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750768Ab1ATTm6 (ORCPT ); Thu, 20 Jan 2011 14:42:58 -0500 Received: from d01dlp01.pok.ibm.com (d01dlp01.pok.ibm.com [9.56.224.56]) by e9.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p0KJIMON029831 for ; Thu, 20 Jan 2011 14:18:23 -0500 Received: from d01relay06.pok.ibm.com (d01relay06.pok.ibm.com [9.56.227.116]) by d01dlp01.pok.ibm.com (Postfix) with ESMTP id BA540728067 for ; Thu, 20 Jan 2011 14:42:41 -0500 (EST) Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay06.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p0KJgfRs2449608 for ; Thu, 20 Jan 2011 14:42:41 -0500 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p0KJgeOF022436 for ; Thu, 20 Jan 2011 14:42:41 -0500 In-Reply-To: <20110120103341.GA8675@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 01/20/2011 04:33 AM, Daniel P. Berrange wrote: > On Thu, Jan 20, 2011 at 09:44:05AM +0100, Gerd Hoffmann wrote: > >> Hi, >> >> >>> For (2), you cannot use bus=X,addr=Y because it makes assumptions about >>> the PCI topology which may change in newer -M pc's. >>> >> Why should the PCI topology for 'pc' ever change? >> >> We'll probably get q35 support some day, but when this lands I >> expect we'll see a new machine type 'q35', so '-m q35' will pick the >> ich9 chipset (which will have a different pci topology of course) >> and '-m pc' will pick the existing piix chipset (which will continue >> to look like it looks today). >> > If the topology does ever change (eg in the kind of way anthony > suggests, first bus only has the graphics card), I think libvirt > is going to need a little work to adapt to the new topology, > regardless of whether we currently specify a bus= arg to -device > or not. I'm not sure there's anything we could do to future proof > us to that kind of change. > I assume that libvirt today assumes that it can use a set of PCI slots in bus 0, correct? Probably in the range 3-31? Such assumptions are very likely to break. Regards, Anthony Liguori > Regards, > Daniel > From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=59009 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pg0PT-0003Ow-Qx for qemu-devel@nongnu.org; Thu, 20 Jan 2011 14:43:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pg0PS-0002vH-09 for qemu-devel@nongnu.org; Thu, 20 Jan 2011 14:43:07 -0500 Received: from e9.ny.us.ibm.com ([32.97.182.139]:46318) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pg0PR-0002v1-U3 for qemu-devel@nongnu.org; Thu, 20 Jan 2011 14:43:05 -0500 Received: from d01dlp01.pok.ibm.com (d01dlp01.pok.ibm.com [9.56.224.56]) by e9.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p0KJHoKX029639 for ; Thu, 20 Jan 2011 14:18:23 -0500 Received: from d01relay06.pok.ibm.com (d01relay06.pok.ibm.com [9.56.227.116]) by d01dlp01.pok.ibm.com (Postfix) with ESMTP id 7B06372804B for ; Thu, 20 Jan 2011 14:42:41 -0500 (EST) Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay06.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p0KJgeTU2216150 for ; Thu, 20 Jan 2011 14:42:40 -0500 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p0KJgeO9022436 for ; Thu, 20 Jan 2011 14:42:40 -0500 Message-ID: <4D38902F.8050604@linux.vnet.ibm.com> Date: Thu, 20 Jan 2011 13:42:39 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 28/35] kvm: x86: Introduce kvmclock device to save/restore its state References: <4D35BD30.1060900@siemens.com> <4D35C1CE.10509@linux.vnet.ibm.com> <4D35C648.7050809@siemens.com> <4D35C92D.7030000@linux.vnet.ibm.com> <4D36B362.70202@redhat.com> <4D371732.5040901@linux.vnet.ibm.com> <20110119171918.GI5113@redhat.com> <4D3722BB.5030407@linux.vnet.ibm.com> <4D37F5D5.3040409@redhat.com> <20110120103341.GA8675@redhat.com> In-Reply-To: <20110120103341.GA8675@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: "kvm@vger.kernel.org" , Jan Kiszka , Glauber Costa , Marcelo Tosatti , Markus Armbruster , "qemu-devel@nongnu.org" , Gerd Hoffmann , Avi Kivity On 01/20/2011 04:33 AM, Daniel P. Berrange wrote: > On Thu, Jan 20, 2011 at 09:44:05AM +0100, Gerd Hoffmann wrote: > >> Hi, >> >> >>> For (2), you cannot use bus=X,addr=Y because it makes assumptions about >>> the PCI topology which may change in newer -M pc's. >>> >> Why should the PCI topology for 'pc' ever change? >> >> We'll probably get q35 support some day, but when this lands I >> expect we'll see a new machine type 'q35', so '-m q35' will pick the >> ich9 chipset (which will have a different pci topology of course) >> and '-m pc' will pick the existing piix chipset (which will continue >> to look like it looks today). >> > If the topology does ever change (eg in the kind of way anthony > suggests, first bus only has the graphics card), I think libvirt > is going to need a little work to adapt to the new topology, > regardless of whether we currently specify a bus= arg to -device > or not. I'm not sure there's anything we could do to future proof > us to that kind of change. > I assume that libvirt today assumes that it can use a set of PCI slots in bus 0, correct? Probably in the range 3-31? Such assumptions are very likely to break. Regards, Anthony Liguori > Regards, > Daniel >