From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41997) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z1zgM-00006P-Dj for qemu-devel@nongnu.org; Mon, 08 Jun 2015 12:13:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z1zgG-0001aU-J9 for qemu-devel@nongnu.org; Mon, 08 Jun 2015 12:13:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59860) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z1zgG-0001aQ-Em for qemu-devel@nongnu.org; Mon, 08 Jun 2015 12:13:44 -0400 Date: Mon, 8 Jun 2015 18:13:40 +0200 From: "Michael S. Tsirkin" Message-ID: <20150608181329-mutt-send-email-mst@redhat.com> References: <55701BED.2090802@redhat.com> <1433510652-13866-1-git-send-email-thibaut.collet@6wind.com> <55752E3C.8070700@redhat.com> <20150608133203.GM23825@stefanha-thinkpad.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [PATCH v2] net: Add support of VIRTIO_NET_F_GUEST_ANNOUNCE for vhost-net/vhost-user List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: Thibaut Collet , Jason Wang , qemu-devel , Stefan Hajnoczi , Juan Quintela On Mon, Jun 08, 2015 at 04:13:59PM +0100, Stefan Hajnoczi wrote: > On Mon, Jun 8, 2015 at 3:05 PM, Thibaut Collet wrote: > >> I think Jason is pointing out that your patch lacks support for guests > >> that do not negotiate VIRTIO_NET_F_GUEST_ANNOUNCE. > > > > I have understood the issue with old guest pointed by Jason. > > I have thinking about the best way to do solve it and any advices are > > welcome. > > 1. Add vhost-user virtio-net command to inject packets > > Add a new VhostUserRequest VHOST_USER_NET_INJECT_PACKET allowing QEMU > to hand a packet to the vhost-user process for injection. This > command is virtio-net specific and fails if called on a different > device type. > > 2. Fail negotiation when VIRTIO_NET_F_GUEST_ANNOUNCE is not accepted > > This is only really possible in VIRTIO 1.0 and later. Pre-1.0 does > not allow the device to reject due to disabled features. > > file:///home/stefanha/virtio/trunk/virtio-v1.0-cs02.html#x1-450001 > > Therefore this is not a great solution. > > 3. The easiest solution - nop .receive() > > Just implement a nop .receive() which drops the packet and prints a > warning message to stderr. This way VIRTIO_NET_F_GUEST_ANNOUNCE > guests work while legacy guests don't send a gratuitous ARP packet. > > Stefan 3 sounds good to me. -- MST