From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [Qemu-devel] [PATCH 28/35] kvm: x86: Introduce kvmclock device to save/restore its state Date: Wed, 19 Jan 2011 18:25:02 +0100 Message-ID: <4D371E6E.8040505@siemens.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> <4D3717E7.3010105@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Markus Armbruster , "kvm@vger.kernel.org" , Glauber Costa , Marcelo Tosatti , "qemu-devel@nongnu.org" , Avi Kivity To: Anthony Liguori Return-path: Received: from david.siemens.de ([192.35.17.14]:16135 "EHLO david.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753244Ab1ASRZV (ORCPT ); Wed, 19 Jan 2011 12:25:21 -0500 In-Reply-To: <4D3717E7.3010105@linux.vnet.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On 2011-01-19 17:57, Anthony Liguori wrote: > On 01/19/2011 07:15 AM, Markus Armbruster wrote: >> So they interact with KVM (need kvm_state), and they interact with the >> emulated PCI bus. Could you elaborate on the fundamental difference >> between the two interactions that makes you choose the (hypothetical) >> KVM bus over the PCI bus as device parent? >> > > It's almost arbitrary, but I would say it's the direction that I/Os flow. We need both if we want KVM buses. They are useless for enumerating the device on that bus the guest sees it on. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=39117 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PfbmV-0004v7-K4 for qemu-devel@nongnu.org; Wed, 19 Jan 2011 12:25:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PfbmO-0006DZ-I2 for qemu-devel@nongnu.org; Wed, 19 Jan 2011 12:25:15 -0500 Received: from david.siemens.de ([192.35.17.14]:16081) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PfbmO-0006Bi-9P for qemu-devel@nongnu.org; Wed, 19 Jan 2011 12:25:08 -0500 Message-ID: <4D371E6E.8040505@siemens.com> Date: Wed, 19 Jan 2011 18:25:02 +0100 From: Jan Kiszka 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> <4D3717E7.3010105@linux.vnet.ibm.com> In-Reply-To: <4D3717E7.3010105@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 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" , Glauber Costa , Marcelo Tosatti , Markus Armbruster , "qemu-devel@nongnu.org" , Avi Kivity On 2011-01-19 17:57, Anthony Liguori wrote: > On 01/19/2011 07:15 AM, Markus Armbruster wrote: >> So they interact with KVM (need kvm_state), and they interact with the >> emulated PCI bus. Could you elaborate on the fundamental difference >> between the two interactions that makes you choose the (hypothetical) >> KVM bus over the PCI bus as device parent? >> > > It's almost arbitrary, but I would say it's the direction that I/Os flow. We need both if we want KVM buses. They are useless for enumerating the device on that bus the guest sees it on. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux