From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [Qemu-devel] KVM call minutes for Feb 8 Date: Sun, 13 Feb 2011 20:08:09 +0200 Message-ID: <20110213180809.GA16327@redhat.com> References: <4D52A86A.1030407@codemonkey.ws> <4D52F20A.7070009@codemonkey.ws> <4D539800.3070802@codemonkey.ws> <4D53BE22.3050706@redhat.com> <4D57FB12.5060703@codemonkey.ws> <4D57FF2E.7020001@redhat.com> <4D580D3E.3000300@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , Blue Swirl , Chris Wright , Markus Armbruster , kvm@vger.kernel.org, qemu-devel@nongnu.org To: Anthony Liguori Return-path: Received: from mx1.redhat.com ([209.132.183.28]:18233 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754194Ab1BMSIO (ORCPT ); Sun, 13 Feb 2011 13:08:14 -0500 Content-Disposition: inline In-Reply-To: <4D580D3E.3000300@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: On Sun, Feb 13, 2011 at 10:56:30AM -0600, Anthony Liguori wrote: > >> > >>qemu -device i440fx,id=nb -device piix3,id=sb,chipset=nb -device > >>ioapic,id=ioapic,chipset=sb -device > >>cpu,ioapic=ioapic,northbridge=nb > >> > >>Is not all that unreasonable and presents a fully functioning PC. > > > >Sure. And -M blah is a shortcut. > > Exactly. Or better yet, blah is a config file that contains > > [device "nb"] > driver=i440fx > You are trying to model how particular (very ancient) HW looked like, instead of emulating guest visible functionality, but is dead end since things are changing constantly. Northbridge functionality moves onto cpu for instance. What CPU i440fx was designed for? Pentium? What if user runs QEMU with emulated CPU that in real life has internal memory controller? Does you config have sense for such setup? Should we allow to specify only Pentium CPU since this is how real HW worked? > [device "sb"] > driver=piix3 And piix3 refers to piix3.cfg which describe devices that present on the chipset. > chipset=nb > > [device "ioapic"] > driver=ioapic > chipset=sb Here, for instance, IOAPIC is included in a chipset for a long time now. Why user should care that piix3 didn't have it. How this detail changes qemu functionality? If it doesn't why should we expose it? > > [device "cpu"] > driver=cpu > ioapic=ioapic Why ioapic here? Doesn't cpu talks to ioapic via northbridge? > northbridge=nb > -- Gleb. From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=56914 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PogMq-0003eo-9S for qemu-devel@nongnu.org; Sun, 13 Feb 2011 13:08:17 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PogMo-0007Rc-Rc for qemu-devel@nongnu.org; Sun, 13 Feb 2011 13:08:16 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35976) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PogMo-0007RH-HQ for qemu-devel@nongnu.org; Sun, 13 Feb 2011 13:08:14 -0500 Date: Sun, 13 Feb 2011 20:08:09 +0200 From: Gleb Natapov Subject: Re: [Qemu-devel] KVM call minutes for Feb 8 Message-ID: <20110213180809.GA16327@redhat.com> References: <4D52A86A.1030407@codemonkey.ws> <4D52F20A.7070009@codemonkey.ws> <4D539800.3070802@codemonkey.ws> <4D53BE22.3050706@redhat.com> <4D57FB12.5060703@codemonkey.ws> <4D57FF2E.7020001@redhat.com> <4D580D3E.3000300@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4D580D3E.3000300@codemonkey.ws> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Chris Wright , kvm@vger.kernel.org, qemu-devel@nongnu.org, Markus Armbruster , Blue Swirl , Avi Kivity On Sun, Feb 13, 2011 at 10:56:30AM -0600, Anthony Liguori wrote: > >> > >>qemu -device i440fx,id=nb -device piix3,id=sb,chipset=nb -device > >>ioapic,id=ioapic,chipset=sb -device > >>cpu,ioapic=ioapic,northbridge=nb > >> > >>Is not all that unreasonable and presents a fully functioning PC. > > > >Sure. And -M blah is a shortcut. > > Exactly. Or better yet, blah is a config file that contains > > [device "nb"] > driver=i440fx > You are trying to model how particular (very ancient) HW looked like, instead of emulating guest visible functionality, but is dead end since things are changing constantly. Northbridge functionality moves onto cpu for instance. What CPU i440fx was designed for? Pentium? What if user runs QEMU with emulated CPU that in real life has internal memory controller? Does you config have sense for such setup? Should we allow to specify only Pentium CPU since this is how real HW worked? > [device "sb"] > driver=piix3 And piix3 refers to piix3.cfg which describe devices that present on the chipset. > chipset=nb > > [device "ioapic"] > driver=ioapic > chipset=sb Here, for instance, IOAPIC is included in a chipset for a long time now. Why user should care that piix3 didn't have it. How this detail changes qemu functionality? If it doesn't why should we expose it? > > [device "cpu"] > driver=cpu > ioapic=ioapic Why ioapic here? Doesn't cpu talks to ioapic via northbridge? > northbridge=nb > -- Gleb.