From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57399) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V6dRO-0007lq-MZ for qemu-devel@nongnu.org; Tue, 06 Aug 2013 05:20:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V6dRI-000883-NV for qemu-devel@nongnu.org; Tue, 06 Aug 2013 05:20:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39587) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V6dRI-00087x-FN for qemu-devel@nongnu.org; Tue, 06 Aug 2013 05:20:24 -0400 Date: Tue, 6 Aug 2013 12:21:48 +0300 From: "Michael S. Tsirkin" Message-ID: <20130806092148.GC11051@redhat.com> References: <51FF6A79.9060603@redhat.com> <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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130806083625.GF8218@redhat.com> 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: Gleb Natapov Cc: Marcel Apfelbaum , seabios@seabios.org, qemu-devel@nongnu.org, Gerd Hoffmann , Paolo Bonzini , Andreas =?iso-8859-1?Q?F=E4rber?= On Tue, Aug 06, 2013 at 11:36:25AM +0300, Gleb Natapov wrote: > 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=0 > > > > Doesn't work for me. > Bug that should be fixed. With this command line _STA should return > zero. It doesn't have anything to do with _STA: device still appears in QOM. It's a QEMU issue, devices that are added with -device are documented in -device help and removed by dropping them from command line. Devices added by default have no way to be dropped from QOM except -nodefaults. > > Besides, both -device pvpanic and use of ioport=0 to disable it > > are completely undocumented. > > > Not the only undocumented thing in QEMU command line :) All -device fields are documented with -device help. This was supposed to be the right way to add all new devices. > > BTW pls keep qemu-devel Cc'd. > > > Haven't touched CC list. > > > > We have different definition of "damage" though. > > > > Driver bugs, qemu bugs, OSPM bugs all can cause issues > > like OS crashes, suspend/resume issues, bad > > performance ... What's your definition of damage? > > > None of those cover the case at hand. Sigh. These examples demonstrate why would user want to run QEMU without the pvpanic device. > -- > Gleb.