From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55606) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V6dLO-0000BP-6w for qemu-devel@nongnu.org; Tue, 06 Aug 2013 05:14:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V6dLH-0005FD-PW for qemu-devel@nongnu.org; Tue, 06 Aug 2013 05:14:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44179) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V6dLH-0005F7-Ge for qemu-devel@nongnu.org; Tue, 06 Aug 2013 05:14:11 -0400 Date: Tue, 6 Aug 2013 12:15:46 +0300 From: "Michael S. Tsirkin" Message-ID: <20130806091546.GB11051@redhat.com> References: <703333176.9515483.1375697447963.JavaMail.root@redhat.com> <20130805151723.GF877@redhat.com> <1970367422.9695773.1375718517492.JavaMail.root@redhat.com> <20130805161833.GA4244@redhat.com> <51FFD6CE.5090302@redhat.com> <20130805182628.GC4244@redhat.com> <20130806072152.GK10891@redhat.com> <20130806083309.GA11051@redhat.com> <20130806083625.GF8218@redhat.com> <5200B78D.2060708@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <5200B78D.2060708@suse.de> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [SeaBIOS] [PATCH] don't expose pvpanic device in the UI List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Andreas =?iso-8859-1?Q?F=E4rber?= Cc: Gleb Natapov , Marcel Apfelbaum , seabios@seabios.org, qemu-devel@nongnu.org, Gerd Hoffmann , Paolo Bonzini On Tue, Aug 06, 2013 at 10:45:01AM +0200, Andreas F=E4rber wrote: > Am 06.08.2013 10:36, schrieb Gleb Natapov: > > On Tue, Aug 06, 2013 at 11:33:10AM +0300, Michael S. Tsirkin wrote: > >> On Tue, Aug 06, 2013 at 10:21:52AM +0300, Gleb Natapov wrote: > >>>> If you see a mouse in a room, how likely is it that there's > >>>> a single mouse there? > >>>> > >>>> This is a PV technology which to me looks like it was > >>>> rushed through and not only set on by default, but > >>>> without a way to disable it - apparently on the assumption > >>>> there's 0 chance it can cause any damage. Now that > >>>> we do know the chance it's not there, why not go back > >>>> to the standard interface, and why not give > >>>> users a chance to enable/disable it? > >>> You should be able to disable it with: -device pvpanic,ioport=3D0 > >> > >> Doesn't work for me. > > Bug that should be fixed. With this command line _STA should return > > zero. > >=20 > >> Besides, both -device pvpanic and use of ioport=3D0 to disable it > >> are completely undocumented. > >> > > Not the only undocumented thing in QEMU command line :) > [snip] >=20 > I disagree: -device adds a device, not removes one. It will still be > present. >=20 > I am neutral as to whether qemu-system-x86_64 should have it enabled by > default or not. But if we want to suppress it, then -nodefaults should > disable it. Since libvirt uses that though, it would mean libvirt would > need to add it back, whether via user's XML domain config or by libvirt > itself based on some version/etc. heuristics. >=20 > Andreas Do you agree that this (-nodefaults does not have pvpanic device by default, -device pvpanic adds it) makes more sense than the proposed alternative: -nodefaults has pvpanic unless an old -M type is specified, ioport=3D0 removes the device? > --=20 > SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg, Germany > GF: Jeff Hawn, Jennifer Guild, Felix Imend=F6rffer; HRB 16746 AG N=FCrn= berg