From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: Re: [Qemu-devel] [PATCH 28/35] kvm: x86: Introduce kvmclock device to save/restore its state Date: Wed, 19 Jan 2011 10:48:18 +0100 Message-ID: <4D36B362.70202@redhat.com> References: <4D2B6CB5.9050602@codemonkey.ws> <4D2B74D8.4080309@web.de> <4D2B8662.9060909@web.de> <4D2C60FB.7030009@linux.vnet.ibm.com> <4D2D80ED.8030405@redhat.com> <4D2D82EE.20002@siemens.com> <4D35A39A.8000801@siemens.com> <4D35ABF8.9050700@linux.vnet.ibm.com> <4D35B521.3090601@siemens.com> <4D35B6DD.1020005@linux.vnet.ibm.com> <4D35B963.7000605@siemens.com> <4D35BA22.7060602@linux.vnet.ibm.com> <4D35BD30.1060900@siemens.com> <4D35C1CE.10509@linux.vnet.ibm.com> <4D35C648.7050809@siemens.com> <4D35C92D.7030000@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Jan Kiszka , Avi Kivity , Markus Armbruster , Marcelo Tosatti , Glauber Costa , "kvm@vger.kernel.org" , "qemu-devel@nongnu.org" To: Anthony Liguori Return-path: Received: from mx1.redhat.com ([209.132.183.28]:7742 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752796Ab1ASJsa (ORCPT ); Wed, 19 Jan 2011 04:48:30 -0500 In-Reply-To: <4D35C92D.7030000@linux.vnet.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On 01/18/11 18:09, Anthony Liguori wrote: > On 01/18/2011 10:56 AM, Jan Kiszka wrote: >> >>> The device model topology is 100% a hidden architectural detail. >> This is true for the sysbus, it is obviously not the case for PCI and >> similarly discoverable buses. There we have a guest-explorable topology >> that is currently equivalent to the the qdev layout. > > But we also don't do PCI passthrough so we really haven't even explored > how that maps in qdev. I don't know if qemu-kvm has attempted to > qdev-ify it. It is qdev-ified. It is a normal pci device from qdev's point of view. BTW: is there any reason why (vfio-based) pci passthrough couldn't work with tcg? > The -device interface is a stable interface. Right now, you don't > specify any type of identifier of the pci bus when you create a PCI > device. It's implied in the interface. Wrong. You can specify the bus you want attach the device to via bus=. This is true for *every* device, including all pci devices. If unspecified qdev uses the first bus it finds. As long as there is a single pci bus only there is simply no need to specify it, thats why nobody does that today. Once q35 finally arrives this will change of course. cheers, Gerd From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=46696 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PfUeV-0006rn-Cq for qemu-devel@nongnu.org; Wed, 19 Jan 2011 04:48:34 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PfUeS-00032T-1p for qemu-devel@nongnu.org; Wed, 19 Jan 2011 04:48:31 -0500 Received: from mx1.redhat.com ([209.132.183.28]:30750) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PfUeR-00030v-Qx for qemu-devel@nongnu.org; Wed, 19 Jan 2011 04:48:28 -0500 Message-ID: <4D36B362.70202@redhat.com> Date: Wed, 19 Jan 2011 10:48:18 +0100 From: Gerd Hoffmann MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 28/35] kvm: x86: Introduce kvmclock device to save/restore its state References: <4D2B6CB5.9050602@codemonkey.ws> <4D2B74D8.4080309@web.de> <4D2B8662.9060909@web.de> <4D2C60FB.7030009@linux.vnet.ibm.com> <4D2D80ED.8030405@redhat.com> <4D2D82EE.20002@siemens.com> <4D35A39A.8000801@siemens.com> <4D35ABF8.9050700@linux.vnet.ibm.com> <4D35B521.3090601@siemens.com> <4D35B6DD.1020005@linux.vnet.ibm.com> <4D35B963.7000605@siemens.com> <4D35BA22.7060602@linux.vnet.ibm.com> <4D35BD30.1060900@siemens.com> <4D35C1CE.10509@linux.vnet.ibm.com> <4D35C648.7050809@siemens.com> <4D35C92D.7030000@linux.vnet.ibm.com> In-Reply-To: <4D35C92D.7030000@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: "kvm@vger.kernel.org" , Jan Kiszka , Glauber Costa , Marcelo Tosatti , Markus Armbruster , "qemu-devel@nongnu.org" , Avi Kivity On 01/18/11 18:09, Anthony Liguori wrote: > On 01/18/2011 10:56 AM, Jan Kiszka wrote: >> >>> The device model topology is 100% a hidden architectural detail. >> This is true for the sysbus, it is obviously not the case for PCI and >> similarly discoverable buses. There we have a guest-explorable topology >> that is currently equivalent to the the qdev layout. > > But we also don't do PCI passthrough so we really haven't even explored > how that maps in qdev. I don't know if qemu-kvm has attempted to > qdev-ify it. It is qdev-ified. It is a normal pci device from qdev's point of view. BTW: is there any reason why (vfio-based) pci passthrough couldn't work with tcg? > The -device interface is a stable interface. Right now, you don't > specify any type of identifier of the pci bus when you create a PCI > device. It's implied in the interface. Wrong. You can specify the bus you want attach the device to via bus=. This is true for *every* device, including all pci devices. If unspecified qdev uses the first bus it finds. As long as there is a single pci bus only there is simply no need to specify it, thats why nobody does that today. Once q35 finally arrives this will change of course. cheers, Gerd