From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: Configuration vs. compat hints [was Re: [Qemu-devel] [PATCHv3 03/13] qemu: add routines to manage PCI capabilities] Date: Mon, 15 Jun 2009 07:45:01 -0500 Message-ID: <4A36424D.3080901@codemonkey.ws> References: <20090610150129.GC28601@redhat.com> <200906101624.30659.paul@codesourcery.com> <20090610174301.GC7416@shareable.org> <20090610182227.GN28601@redhat.com> <20090610192702.GH7416@shareable.org> <1244796209.16425.20.camel@blaa> <4A326B5C.5010501@codemonkey.ws> <1244821292.30522.56.camel@blaa> <4A327E4A.7010300@codemonkey.ws> <1244825303.26769.19.camel@blaa> <20090614095016.GA7560@redhat.com> <4A3617D4.5090405@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Michael S. Tsirkin" , Mark McLoughlin , Jamie Lokier , Carsten Otte , kvm@vger.kernel.org, Glauber Costa , Rusty Russell , qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, Blue Swirl , Christian Borntraeger , Paul Brook To: Avi Kivity Return-path: Received: from mail-qy0-f173.google.com ([209.85.221.173]:48779 "EHLO mail-qy0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752721AbZFOMpF (ORCPT ); Mon, 15 Jun 2009 08:45:05 -0400 Received: by qyk3 with SMTP id 3so229731qyk.33 for ; Mon, 15 Jun 2009 05:45:05 -0700 (PDT) In-Reply-To: <4A3617D4.5090405@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Avi Kivity wrote: > On 06/14/2009 12:50 PM, Michael S. Tsirkin wrote: >> On Fri, Jun 12, 2009 at 05:48:23PM +0100, Mark McLoughlin wrote: >> >>> However, in order to retain compat for that SCSI device (e.g. ensuring >>> the PCI address doesn't change as other devices are added an removed), >>> we're back to the same problem ... either: >>> >>> 1) Use '-drive file=foo.img,if=scsi,pci_addr=foo'; in order to >>> figure >>> out what address to use, libvirt would need to query qemu for >>> what >>> address was originally allocated to device or it would do all the >>> PCI address allocation itself ... >>> >> >> This last option makes sense to me: in a real world the user has >> control over where he places the device on the bus, so why >> not with qemu? >> > > Yes, the user build the machine using the command line and monitor > (or, in 2017, the machine configuration file), Considering pbrook just posted a machine config for arm, I think it would be rather sad if pc wasn't converted to it by 2017... > then turns on the power. Command line options are the parts lying > around when we start. > > btw, -drive needs to be separated: > > -controller type=lsi1234,pci_addr=foobar,name=blah > -drive file=foo.img,controller=blah,index=0 > -drive file=bar.img,controller=blah,index=1 > > Drives to not have pci addresses. Drivers don't have indexes and buses but we specify it on the -drive line. -drive is convenient syntax. It stops being convenient when you force it to be two options. Regards, Anthony Liguori