From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43962) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YssZg-0000zI-Rt for qemu-devel@nongnu.org; Thu, 14 May 2015 08:49:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YssZd-0008PH-Jy for qemu-devel@nongnu.org; Thu, 14 May 2015 08:49:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47242) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YssZd-0008OE-CK for qemu-devel@nongnu.org; Thu, 14 May 2015 08:49:13 -0400 Date: Thu, 14 May 2015 13:48:56 +0100 From: "Daniel P. Berrange" Message-ID: <20150514124856.GG3441@redhat.com> References: <20150513174204.GS23627@redhat.com> <5553C651.4060000@redhat.com> <20150514111825.GE3441@redhat.com> <878ucr4bb7.fsf@blackfin.pond.sub.org> <555490EE.1040802@redhat.com> <87egmjz5sl.fsf@blackfin.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <87egmjz5sl.fsf@blackfin.pond.sub.org> Subject: Re: [Qemu-devel] [PATCH] Do not emulate a floppy drive when -nodefaults Reply-To: "Daniel P. Berrange" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: Kevin Wolf , xen-devel@lists.xensource.com, Stefano Stabellini , mst@redhat.com, qemu-devel@nongnu.org, Paolo Bonzini , John Snow , rth@twiddle.net On Thu, May 14, 2015 at 02:45:30PM +0200, Markus Armbruster wrote: > Paolo Bonzini writes: > > > On 14/05/2015 14:02, Markus Armbruster wrote: > >> It should certainly be off for pc-q35-2.4 and newer. Real Q35 boards > >> commonly don't have an FDC (depends on the Super I/O chip used). > >> > >> We may want to keep it off for pc-i440fx-2.4 and newer. I doubt > >> there's a real i440FX without an FDC, but our virtual i440FX is quite > >> unlike a real one in other ways already. > > > > That would break libvirt for people upgrading from 2.3 to 2.4. So it's > > more like pc-i440fx-3.0 and pc-q35-3.0. > > What exactly breaks when? [quote] * Create the FDC only if the option is "on". * Optional: make -drive if=floppy,... auto-enable it I wouldn't bother doing the same for -global isa-fdc.driveA=... and such. [/quote] Libvirt uses -global when enabling floppy devices. So since current libvirt does not know about the new (to be created) machine type property to turn on FDC, it will get an error using -global isa-fdc.driveA= I'm not too bothered about this, as long as libvirt has enough advance notice to add support for the new machine type property to enable FDC before we change its default value to be "off". Perhaps one QEMU major release cycle before toggling the default, to give time for new libvirt to penetrate to distros Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel P. Berrange" Subject: Re: [PATCH] Do not emulate a floppy drive when -nodefaults Date: Thu, 14 May 2015 13:48:56 +0100 Message-ID: <20150514124856.GG3441@redhat.com> References: <20150513174204.GS23627@redhat.com> <5553C651.4060000@redhat.com> <20150514111825.GE3441@redhat.com> <878ucr4bb7.fsf@blackfin.pond.sub.org> <555490EE.1040802@redhat.com> <87egmjz5sl.fsf@blackfin.pond.sub.org> Reply-To: "Daniel P. Berrange" Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <87egmjz5sl.fsf@blackfin.pond.sub.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org To: Markus Armbruster Cc: Kevin Wolf , xen-devel@lists.xensource.com, Stefano Stabellini , mst@redhat.com, qemu-devel@nongnu.org, Paolo Bonzini , John Snow , rth@twiddle.net List-Id: xen-devel@lists.xenproject.org On Thu, May 14, 2015 at 02:45:30PM +0200, Markus Armbruster wrote: > Paolo Bonzini writes: > > > On 14/05/2015 14:02, Markus Armbruster wrote: > >> It should certainly be off for pc-q35-2.4 and newer. Real Q35 boards > >> commonly don't have an FDC (depends on the Super I/O chip used). > >> > >> We may want to keep it off for pc-i440fx-2.4 and newer. I doubt > >> there's a real i440FX without an FDC, but our virtual i440FX is quite > >> unlike a real one in other ways already. > > > > That would break libvirt for people upgrading from 2.3 to 2.4. So it's > > more like pc-i440fx-3.0 and pc-q35-3.0. > > What exactly breaks when? [quote] * Create the FDC only if the option is "on". * Optional: make -drive if=floppy,... auto-enable it I wouldn't bother doing the same for -global isa-fdc.driveA=... and such. [/quote] Libvirt uses -global when enabling floppy devices. So since current libvirt does not know about the new (to be created) machine type property to turn on FDC, it will get an error using -global isa-fdc.driveA= I'm not too bothered about this, as long as libvirt has enough advance notice to add support for the new machine type property to enable FDC before we change its default value to be "off". Perhaps one QEMU major release cycle before toggling the default, to give time for new libvirt to penetrate to distros Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|