From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [PATCH qemu-kvm] Add raw(af_packet) network backend to qemu Date: Wed, 27 Jan 2010 08:07:11 -0600 Message-ID: <4B60488F.5020506@codemonkey.ws> References: <1264538423.24933.144.camel@w-sridhar.beaverton.ibm.com> <4B5F54E8.3080507@codemonkey.ws> <4B5F5594.6080006@codemonkey.ws> <20100127092451.GC3476@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Sridhar Samudrala , avi@redhat.com, markmc@redhat.com, ogerlitz@voltaire.com, kvm@vger.kernel.org, qemu-devel@vger.kernel.org To: "Michael S. Tsirkin" Return-path: Received: from mail-iw0-f186.google.com ([209.85.223.186]:59199 "EHLO mail-iw0-f186.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753514Ab0A0OHP (ORCPT ); Wed, 27 Jan 2010 09:07:15 -0500 In-Reply-To: <20100127092451.GC3476@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 01/27/2010 03:24 AM, Michael S. Tsirkin wrote: > I am not sure I agree with this sentiment. The main issue being that > macvtap doesn't exist on all kernels :). Neither does vhost ;-) If it were just that as the difference, I'd be inclined to agree, but macvtap is much better from a security PoV. >> Not to mention that from a user perspective, raw makes almost no sense >> as it's an obscure socket protocol family. >> >> A user wants to do useful things like bridged networking or direct VF >> assignment. We should have -net backends that reflect things that make >> sense to a user. >> >> Regards, >> >> Anthony Liguori >> > > I agree to that. People don't even seem to agree whether it's a raw > socket or a packet socket :) We need a better name for this option: what > it really does is rely on an external device to loopback a packet to us, > so how about -net loopback or -net extbridge? > Specifically for VEPA, something like: -net extbridge,if=eth0 or even -net vepa,if=eth0 Would be fantastic. I think the best way to achieve this is to introduce a small helper that gets called and can create a macvtap device and hand the file descriptor back to qemu :-) A builtin backend would also be fine since we don't have the helper infrastructure. Regards, Anthony Liguori