From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=47502 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PmRU3-0006K1-VY for qemu-devel@nongnu.org; Mon, 07 Feb 2011 08:50:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PmRU2-0007g0-7L for qemu-devel@nongnu.org; Mon, 07 Feb 2011 08:50:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:1528) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PmRU1-0007fk-Rz for qemu-devel@nongnu.org; Mon, 07 Feb 2011 08:50:26 -0500 Date: Mon, 7 Feb 2011 15:50:01 +0200 From: "Michael S. Tsirkin" Message-ID: <20110207135001.GA23844@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] [PATCH] vhost: disable on tap link down List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, Sridhar Samudrala , Alex Williamson , Juan Quintela , jasowang@redhat.com, Jes.Sorensen@redhat.com Cc: pradeep qemu makes it possible to disable link at tap which is not communicated to the guest but causes all packets to be dropped. Handle this with vhost simply by moving to the userspace emulation. Note: it might be a good idea to make peer link status match tap in this case, so the guest gets an event and updates the carrier state. For now stay bug for bug compatible with what we used to have. Signed-off-by: Michael S. Tsirkin Reported-by: pradeep --- Untested. Pradeep, mind trying this patch out and reporting? Thanks! hw/virtio-net.c | 4 ++++ net.c | 7 +++++++ 2 files changed, 11 insertions(+), 0 deletions(-) diff --git a/hw/virtio-net.c b/hw/virtio-net.c index 671d952..fc2d6f5 100644 --- a/hw/virtio-net.c +++ b/hw/virtio-net.c @@ -112,6 +112,10 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status) return; } + if (n->nic->nc.peer->link_down) { + return; + } + if (!tap_get_vhost_net(n->nic->nc.peer)) { return; } diff --git a/net.c b/net.c index 9ba5be2..57ee997 100644 --- a/net.c +++ b/net.c @@ -1324,6 +1324,13 @@ done: if (vc->info->link_status_changed) { vc->info->link_status_changed(vc); } + + /* Notify peer. Don't update peer link status: this makes it possible to + * disconnect from host network without notifying the guest. + * FIXME: is this useful? Could just be an artifact of vlan support. */ + if (vc->peer && vc->peer->info->link_status_changed) { + vc->peer->info->link_status_changed(vc->peer); + } return 0; } -- 1.7.3.2.91.g446ac