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: Tue, 26 Jan 2010 14:50:28 -0600 Message-ID: <4B5F5594.6080006@codemonkey.ws> References: <1264538423.24933.144.camel@w-sridhar.beaverton.ibm.com> <4B5F54E8.3080507@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: avi@redhat.com, markmc@redhat.com, "Michael S. Tsirkin" , ogerlitz@voltaire.com, kvm@vger.kernel.org, qemu-devel@vger.kernel.org To: Sridhar Samudrala Return-path: Received: from mail-fx0-f220.google.com ([209.85.220.220]:34722 "EHLO mail-fx0-f220.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752270Ab0AZUue (ORCPT ); Tue, 26 Jan 2010 15:50:34 -0500 In-Reply-To: <4B5F54E8.3080507@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: On 01/26/2010 02:47 PM, Anthony Liguori wrote: > On 01/26/2010 02:40 PM, Sridhar Samudrala wrote: >> This patch adds raw socket backend to qemu and is based on Or Gerlitz's >> patch re-factored and ported to the latest qemu-kvm git tree. >> It also includes support for vnet_hdr option that enables gso/checksum >> offload with raw backend. You can find the linux kernel patch to support >> this feature here. >> http://thread.gmane.org/gmane.linux.network/150308 >> >> Signed-off-by: Sridhar Samudrala > > See the previous discussion about the raw backend from Or's original > patch. There's no obvious reason why we should have this in addition > to a tun/tap backend. > > The only use-case I know of is macvlan but macvtap addresses this > functionality while not introduce the rather nasty security problems > associated with a raw backend. 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