From cd7d1d26b0a333bf2fca715e332690bbd738c097 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Tue, 19 Aug 2014 12:56:29 +0800 Subject: vhost_net: start/stop guest notifiers properly 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. To fix this, several other changes are needed: - remove the hdev->started assertion in vhost.c since we may want to start the guest notifiers before vhost starts and stop the guest notifiers after vhost is stopped. - introduce the vhost_net_set_vq_index() and call it before setting guest notifiers. This is to guarantee vhost_net has the correct virtqueue index when setting guest notifiers. MST: fix up error handling. Cc: qemu-stable@nongnu.org Cc: Jason Wang Signed-off-by: Michael S. Tsirkin Tested-by: Andrey Korolyov Reported-by: "Zhangjie (HZ)" Tested-by: William Dauchy Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin --- hw/net/vhost_net.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) (limited to 'hw/net') diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index 9bbf2ee4ce..3819044b02 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -188,16 +188,19 @@ bool vhost_net_query(VHostNetState *net, VirtIODevice *dev) return vhost_dev_query(&net->dev, dev); } +static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index) +{ + net->dev.vq_index = vq_index; +} + static int vhost_net_start_one(struct vhost_net *net, - VirtIODevice *dev, - int vq_index) + VirtIODevice *dev) { struct vhost_vring_file file = { }; int r; net->dev.nvqs = 2; net->dev.vqs = net->vqs; - net->dev.vq_index = vq_index; r = vhost_dev_enable_notifiers(&net->dev, dev); if (r < 0) { @@ -286,7 +289,7 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs, BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev))); VirtioBusState *vbus = VIRTIO_BUS(qbus); VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); - int r, i = 0; + int r, e, i; if (!vhost_net_device_endian_ok(dev)) { error_report("vhost-net does not support cross-endian"); @@ -301,11 +304,7 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs, } for (i = 0; i < total_queues; i++) { - r = vhost_net_start_one(get_vhost_net(ncs[i].peer), dev, i * 2); - - if (r < 0) { - goto err; - } + vhost_net_set_vq_index(get_vhost_net(ncs[i].peer), i * 2); } r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true); @@ -314,12 +313,26 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs, goto err; } + for (i = 0; i < total_queues; i++) { + r = vhost_net_start_one(get_vhost_net(ncs[i].peer), dev); + + if (r < 0) { + goto err_start; + } + } + return 0; -err: +err_start: while (--i >= 0) { vhost_net_stop_one(get_vhost_net(ncs[i].peer), dev); } + e = k->set_guest_notifiers(qbus->parent, total_queues * 2, false); + if (e < 0) { + fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e); + fflush(stderr); + } +err: return r; } @@ -331,16 +344,16 @@ 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) -- cgit v1.2.3 From b49ae9138d5cadb47fb868297fbcdac8292fb666 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Wed, 3 Sep 2014 14:25:30 +0800 Subject: vhost_net: init acked_features to backend_features commit 2e6d46d77ed328d34a94688da8371bcbe243479b (vhost: add vhost_get_features and vhost_ack_features) removes the step that initializes the acked_features to backend_features. As this field is now uninitialized, vhost initialization will sometimes fail. To fix, initialize acked_features on each ack. Tested-by: Andrey Korolyov Cc: Nikolay Nikolaev Cc: qemu-stable@nongnu.org Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/net/vhost_net.c | 1 + 1 file changed, 1 insertion(+) (limited to 'hw/net') diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index 3819044b02..b21e7a434f 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -115,6 +115,7 @@ unsigned vhost_net_get_features(struct vhost_net *net, unsigned features) void vhost_net_ack_features(struct vhost_net *net, unsigned features) { + net->dev.acked_features = net->dev.backend_features; vhost_ack_features(&net->dev, vhost_net_get_feature_bits(net), features); } -- cgit v1.2.3