netvsc: make sure and unregister datapath

Go back to switching datapath directly in the notifier callback.
Otherwise datapath might not get switched on unregister.

No need for calling the NOTIFY_PEERS notifier since that is only for
a gratitious ARP/ND packet; but that is not required with Hyper-V
because both VF and synthetic NIC have the same MAC address.

Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Fixes: 0c195567a8f6 ("netvsc: transparent VF management")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index c701b05..d1ea99a 100644 (file)
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -724,14 +724,11 @@ struct net_device_context {
        struct net_device __rcu *vf_netdev;
        struct netvsc_vf_pcpu_stats __percpu *vf_stats;
        struct work_struct vf_takeover;
-       struct work_struct vf_notify;
 
        /* 1: allocated, serial number is valid. 0: not allocated */
        u32 vf_alloc;
        /* Serial number of the VF to team with */
        u32 vf_serial;
-
-       bool datapath;  /* 0 - synthetic, 1 - VF nic */
 };
 
 /* Per channel data */

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 9598220..208f03a 100644 (file)
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -60,8 +60,6 @@ void netvsc_switch_datapath(struct net_device *ndev, bool vf)
                               sizeof(struct nvsp_message),
                               (unsigned long)init_pkt,
                               VM_PKT_DATA_INBAND, 0);
-
-       net_device_ctx->datapath = vf;
 }
 
 static struct netvsc_device *alloc_net_device(void)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index e75c0f8..eb0023f 100644 (file)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1649,55 +1649,35 @@ static int netvsc_register_vf(struct net_device *vf_netdev)
        return NOTIFY_OK;
 }
 
-/* Change datapath */
-static void netvsc_vf_update(struct work_struct *w)
+static int netvsc_vf_up(struct net_device *vf_netdev)
 {
-       struct net_device_context *ndev_ctx
-               = container_of(w, struct net_device_context, vf_notify);
-       struct net_device *ndev = hv_get_drvdata(ndev_ctx->device_ctx);
+       struct net_device_context *net_device_ctx;
        struct netvsc_device *netvsc_dev;
-       struct net_device *vf_netdev;
-       bool vf_is_up;
-
-       if (!rtnl_trylock()) {
-               schedule_work(w);
-               return;
-       }
+       struct net_device *ndev;
 
-       vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
-       if (!vf_netdev)
-               goto unlock;
+       ndev = get_netvsc_byref(vf_netdev);
+       if (!ndev)
+               return NOTIFY_DONE;
 
-       netvsc_dev = rtnl_dereference(ndev_ctx->nvdev);
+       net_device_ctx = netdev_priv(ndev);
+       netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
        if (!netvsc_dev)
-               goto unlock;
-
-       vf_is_up = netif_running(vf_netdev);
-       if (vf_is_up != ndev_ctx->datapath) {
-               if (vf_is_up) {
-                       netdev_info(ndev, "VF up: %s\n", vf_netdev->name);
-                       rndis_filter_open(netvsc_dev);
-                       netvsc_switch_datapath(ndev, true);
-                       netdev_info(ndev, "Data path switched to VF: %s\n",
-                                   vf_netdev->name);
-               } else {
-                       netdev_info(ndev, "VF down: %s\n", vf_netdev->name);
-                       netvsc_switch_datapath(ndev, false);
-                       rndis_filter_close(netvsc_dev);
-                       netdev_info(ndev, "Data path switched from VF: %s\n",
-                                   vf_netdev->name);
-               }
+               return NOTIFY_DONE;
 
-               /* Now notify peers through VF device. */
-               call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, ndev);
-       }
-unlock:
-       rtnl_unlock();
+       /* Bump refcount when datapath is acvive - Why? */
+       rndis_filter_open(netvsc_dev);
+
+       /* notify the host to switch the data path. */
+       netvsc_switch_datapath(ndev, true);
+       netdev_info(ndev, "Data path switched to VF: %s\n", vf_netdev->name);
+
+       return NOTIFY_OK;
 }
 
-static int netvsc_vf_notify(struct net_device *vf_netdev)
+static int netvsc_vf_down(struct net_device *vf_netdev)
 {
        struct net_device_context *net_device_ctx;
+       struct netvsc_device *netvsc_dev;
        struct net_device *ndev;
 
        ndev = get_netvsc_byref(vf_netdev);
@@ -1705,7 +1685,13 @@ static int netvsc_vf_notify(struct net_device *vf_netdev)
                return NOTIFY_DONE;
 
        net_device_ctx = netdev_priv(ndev);
-       schedule_work(&net_device_ctx->vf_notify);
+       netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
+       if (!netvsc_dev)
+               return NOTIFY_DONE;
+
+       netvsc_switch_datapath(ndev, false);
+       netdev_info(ndev, "Data path switched from VF: %s\n", vf_netdev->name);
+       rndis_filter_close(netvsc_dev);
 
        return NOTIFY_OK;
 }
@@ -1721,7 +1707,6 @@ static int netvsc_unregister_vf(struct net_device *vf_netdev)
 
        net_device_ctx = netdev_priv(ndev);
        cancel_work_sync(&net_device_ctx->vf_takeover);
-       cancel_work_sync(&net_device_ctx->vf_notify);
 
        netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name);
 
@@ -1764,7 +1749,6 @@ static int netvsc_probe(struct hv_device *dev,
        spin_lock_init(&net_device_ctx->lock);
        INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
        INIT_WORK(&net_device_ctx->vf_takeover, netvsc_vf_setup);
-       INIT_WORK(&net_device_ctx->vf_notify, netvsc_vf_update);
 
        net_device_ctx->vf_stats
                = netdev_alloc_pcpu_stats(struct netvsc_vf_pcpu_stats);
@@ -1915,8 +1899,9 @@ static int netvsc_netdev_event(struct notifier_block *this,
        case NETDEV_UNREGISTER:
                return netvsc_unregister_vf(event_dev);
        case NETDEV_UP:
+               return netvsc_vf_up(event_dev);
        case NETDEV_DOWN:
-               return netvsc_vf_notify(event_dev);
+               return netvsc_vf_down(event_dev);
        default:
                return NOTIFY_DONE;
        }