From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52458) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XEH9p-0005po-8r for qemu-devel@nongnu.org; Mon, 04 Aug 2014 08:14:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XEH9k-0005dC-EO for qemu-devel@nongnu.org; Mon, 04 Aug 2014 08:14:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43934) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XEH9k-0005d7-5T for qemu-devel@nongnu.org; Mon, 04 Aug 2014 08:14:24 -0400 Date: Mon, 4 Aug 2014 14:14:32 +0200 From: "Michael S. Tsirkin" Message-ID: <1407154415-13621-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] [PATCH] vhost_net: stop guest notifiers after backend List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: "Zhangjie (HZ)" commit a9f98bb5ebe6fb1869321dcc58e72041ae626ad8 vhost: multiqueue support changed the order of stopping the device. Previously vhost_dev_stop would disable backend and only afterwards, unset guest notifiers. We now unset guest notifiers while vhost is still active. This can lose interrupts causing guest networking to fail. In particular, this has been observed during migration. Reported-by: "Zhangjie (HZ)" Signed-off-by: Michael S. Tsirkin --- Zhangjie could you please confirm that this fixes the problem for you? hw/net/vhost_net.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index f87c798..41d5158 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -308,6 +308,12 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs, goto err; } + r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true); + if (r < 0) { + error_report("Error binding guest notifier: %d", -r); + goto err; + } + for (i = 0; i < total_queues; i++) { r = vhost_net_start_one(get_vhost_net(ncs[i].peer), dev, i * 2); @@ -316,12 +322,6 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs, } } - r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true); - if (r < 0) { - error_report("Error binding guest notifier: %d", -r); - goto err; - } - return 0; err: @@ -339,16 +339,16 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs, VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); int i, r; + for (i = 0; i < total_queues; i++) { + vhost_net_stop_one(get_vhost_net(ncs[i].peer), dev); + } + r = k->set_guest_notifiers(qbus->parent, total_queues * 2, false); if (r < 0) { fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", r); fflush(stderr); } assert(r >= 0); - - for (i = 0; i < total_queues; i++) { - vhost_net_stop_one(get_vhost_net(ncs[i].peer), dev); - } } void vhost_net_cleanup(struct vhost_net *net) -- MST