From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MvWxe-0001kn-AZ for qemu-devel@nongnu.org; Wed, 07 Oct 2009 09:53:46 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MvWxZ-0001hA-D2 for qemu-devel@nongnu.org; Wed, 07 Oct 2009 09:53:45 -0400 Received: from [199.232.76.173] (port=49495 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MvWxZ-0001gv-77 for qemu-devel@nongnu.org; Wed, 07 Oct 2009 09:53:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:26476) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MvWxY-0008Qe-FX for qemu-devel@nongnu.org; Wed, 07 Oct 2009 09:53:40 -0400 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n97DrdVj006543 for ; Wed, 7 Oct 2009 09:53:39 -0400 Date: Wed, 7 Oct 2009 19:23:01 +0530 From: Amit Shah Subject: Re: [Qemu-devel] [PATCH 3/6] virtio-console: Add a virtio-console bus, support for multiple ports Message-ID: <20091007135301.GD22238@amit-x200.redhat.com> References: <4AC46A7A.6030809@redhat.com> <20091001085620.GB8385@amit-x200.redhat.com> <20091001104843.GA12334@amit-x200.redhat.com> <4AC49D79.9070800@redhat.com> <20091007092519.GB29515@amit-x200.redhat.com> <4ACC6492.6010808@redhat.com> <20091007100641.GC29515@amit-x200.redhat.com> <4ACC7CA5.4030704@redhat.com> <20091007114257.GA22238@amit-x200.redhat.com> <4ACC9240.4040008@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4ACC9240.4040008@redhat.com> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: qemu-devel@nongnu.org On (Wed) Oct 07 2009 [15:06:08], Gerd Hoffmann wrote: > On 10/07/09 13:42, Amit Shah wrote: >> On (Wed) Oct 07 2009 [13:33:57], Gerd Hoffmann wrote: >>> Second, the bus= argument is optional. If not specified, qdev will pick >>> the first bus of a matching type it finds. So as long you have a single >>> port/scsi/usb/... bus only you don't need bus= at all. You can do: >> >> The problem with this is that the management solution needs to know then >> what is the default bus name (which could change if the code gets >> updated). > > No problem. Just don't use -virtioconsole. Go with -device > virtio-serial-bus,id=... + -device virtport,bus=.. then and explicitly > name your devices (and thereby the buses too). > > -virtioconsole should *really* be a pure backward compatibility thing. > Use case: You have a script starting qemu using -virtioconsole. After > upgrading qemu it should continue to work, i.e. create a device which > the guest can use as before the upgrade and which is linked up to a > chardev as it was before. > > Anything which wants to use the new features can (and should) completely > ignore -virtioconsole. I just wanted to point out that mixing old and > new style is *possible*. It wasn't my intention to imply that I > *recommend* doing that. There should be some way of deprecating commands in qemu. Maybe in 1-2 release cycles. >> And also there's the other problem of a console port spawning a bus >> (which could end up spawning another console port at #0...) > > parse error. > I don't understand what problem you are trying to point out. Oh; I was stuck at the earlier suggestion made by you: -device virtio-serial-pci,chardev=... which implies -device virtioconsole (with a port at id 0) and then someone also doing -virtioconsole ... which would end up creating another bus for this current backward compat reason. Amit