hyperv: Fix race between probe and open calls

Moving the register_netdev to the end of probe to prevent
possible open call happens before NetVSP is connected.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 12 deletions

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index f8135725bcf6..71baeb3ed905 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -261,9 +261,7 @@ int netvsc_recv_callback(struct hv_device *device_obj,
         struct sk_buff *skb;
 
         net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
-        if (!net) {
-                netdev_err(net, "got receive callback but net device"
-                        " not initialized yet\n");
+        if (!net || net->reg_state != NETREG_REGISTERED) {
                 packet->status = NVSP_STAT_FAIL;
                 return 0;
         }
@@ -435,19 +433,11 @@ static int netvsc_probe(struct hv_device *dev,
         SET_ETHTOOL_OPS(net, &ethtool_ops);
         SET_NETDEV_DEV(net, &dev->device);
 
-        ret = register_netdev(net);
-        if (ret != 0) {
-                pr_err("Unable to register netdev.\n");
-                free_netdev(net);
-                goto out;
-        }
-
         /* Notify the netvsc driver of the new device */
         device_info.ring_size = ring_size;
         ret = rndis_filter_device_add(dev, &device_info);
         if (ret != 0) {
                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
-                unregister_netdev(net);
                 free_netdev(net);
                 hv_set_drvdata(dev, NULL);
                 return ret;
@@ -456,7 +446,13 @@ static int netvsc_probe(struct hv_device *dev,
 
         netif_carrier_on(net);
 
-out:
+        ret = register_netdev(net);
+        if (ret != 0) {
+                pr_err("Unable to register netdev.\n");
+                rndis_filter_device_remove(dev);
+                free_netdev(net);
+        }
+
         return ret;
 }