From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1N66Lx-0002Q7-H3 for qemu-devel@nongnu.org; Thu, 05 Nov 2009 12:42:33 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1N66Ls-0002FP-89 for qemu-devel@nongnu.org; Thu, 05 Nov 2009 12:42:32 -0500 Received: from [199.232.76.173] (port=43642 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1N66Ls-0002FC-01 for qemu-devel@nongnu.org; Thu, 05 Nov 2009 12:42:28 -0500 Received: from e32.co.us.ibm.com ([32.97.110.150]:41790) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1N66Lr-0003WK-Jj for qemu-devel@nongnu.org; Thu, 05 Nov 2009 12:42:27 -0500 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by e32.co.us.ibm.com (8.14.3/8.13.1) with ESMTP id nA5HbFWq029594 for ; Thu, 5 Nov 2009 10:37:15 -0700 Received: from d03av06.boulder.ibm.com (d03av06.boulder.ibm.com [9.17.195.245]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id nA5HgMSL030632 for ; Thu, 5 Nov 2009 10:42:22 -0700 Received: from d03av06.boulder.ibm.com (loopback [127.0.0.1]) by d03av06.boulder.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id nA5Hhulb011129 for ; Thu, 5 Nov 2009 10:43:57 -0700 Message-ID: <4AF30E7A.5020708@us.ibm.com> Date: Thu, 05 Nov 2009 11:42:18 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 0/4] net-bridge: rootless bridge support for qemu References: <1257294485-27015-1-git-send-email-aliguori@us.ibm.com> <20091105163702.GC21630@shareable.org> <4AF30129.7080203@us.ibm.com> <200911051820.48878.arnd@arndb.de> In-Reply-To: <200911051820.48878.arnd@arndb.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Arnd Bergmann Cc: Mark McLoughlin , Arnd Bergmann , Juan Quintela , Dustin Kirkland , qemu-devel@nongnu.org, Michael Tsirkin , Avi Kivity Arnd Bergmann wrote: > On Thursday 05 November 2009, Anthony Liguori wrote: > >>> It'd still install the default helper you've provided and use it by >>> default, of course. >>> >>> >> That's already how it behaves. You can say -net >> bridge,helper=/usr/local/bin/my-helper >> >> > > How about abstracting it further and not making the helper depend on > bridge code. If we put the helper into netcf, we could make that > a more generic '-net netcf,helper=/usr/bin/netcf-helper' target, > Your suggestion on irc of doing -net tap,helper="/usr/bin/netcf-helper --name=foo" would also do the trick. For qemu-bridge-helper, it would be -net tap,helper="/usr/libexec/qemu-bridge-helper --bridge=qemubr0". I'd still want to have -net bridge syntax but it's just a syntatic wrapper (like -hda). It's not something that would be used by libvirt, for instance. Whether qemu-bridge-helper should live in qemu is another point to think about. I think I would like to start with it being in qemu but then hope someone else pulls it into a separate project along with tunctl. I think one can really make the argument that qemu should never allocate tap devices directly. It should either get a file descriptor or call out to a helper to allocate a tap device and configure however is needed. Both cases allow an unprivileged qemu whereas qemu creating a device directly clearly doesn't. Maybe we could even eventually get rid of all of the tap code and replace it with a generic helper. -- Regards, Anthony Liguori