4 files changed, 19 insertions, 8 deletions

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index d6c25580f8dd..12cc64bfcff8 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -765,7 +765,8 @@ struct netvsc_device {
 	u32 max_chn;
 	u32 num_chn;
 
-	refcount_t sc_offered;
+	atomic_t open_chn;
+	wait_queue_head_t subchan_open;
 
 	struct rndis_device *extension;
 
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 0a9167dd72fb..d18c3326a1f7 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -78,6 +78,7 @@ static struct netvsc_device *alloc_net_device(void)
 	net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
 	net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
 	init_completion(&net_device->channel_init_wait);
+	init_waitqueue_head(&net_device->subchan_open);
 
 	return net_device;
 }
@@ -1302,6 +1303,8 @@ int netvsc_device_add(struct hv_device *device,
 		struct netvsc_channel *nvchan = &net_device->chan_table[i];
 
 		nvchan->channel = device->channel;
+		u64_stats_init(&nvchan->tx_stats.syncp);
+		u64_stats_init(&nvchan->rx_stats.syncp);
 	}
 
 	/* Enable NAPI handler before init callbacks */
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 0d78727f1a14..d91cbc6c3ca4 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1269,7 +1269,12 @@ static void netvsc_link_change(struct work_struct *w)
 	bool notify = false, reschedule = false;
 	unsigned long flags, next_reconfig, delay;
 
-	rtnl_lock();
+	/* if changes are happening, comeback later */
+	if (!rtnl_trylock()) {
+		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
+		return;
+	}
+
 	net_device = rtnl_dereference(ndev_ctx->nvdev);
 	if (!net_device)
 		goto out_unlock;
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 85c00e1c52b6..d6308ffda53e 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1048,8 +1048,8 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 	else
 		netif_napi_del(&nvchan->napi);
 
-	if (refcount_dec_and_test(&nvscdev->sc_offered))
-		complete(&nvscdev->channel_init_wait);
+	atomic_inc(&nvscdev->open_chn);
+	wake_up(&nvscdev->subchan_open);
 }
 
 int rndis_filter_device_add(struct hv_device *dev,
@@ -1090,8 +1090,6 @@ int rndis_filter_device_add(struct hv_device *dev,
 	net_device->max_chn = 1;
 	net_device->num_chn = 1;
 
-	refcount_set(&net_device->sc_offered, 0);
-
 	net_device->extension = rndis_device;
 	rndis_device->ndev = net;
 
@@ -1221,11 +1219,11 @@ int rndis_filter_device_add(struct hv_device *dev,
 		rndis_device->ind_table[i] = ethtool_rxfh_indir_default(i,
 							net_device->num_chn);
 
+	atomic_set(&net_device->open_chn, 1);
 	num_rss_qs = net_device->num_chn - 1;
 	if (num_rss_qs == 0)
 		return 0;
 
-	refcount_set(&net_device->sc_offered, num_rss_qs);
 	vmbus_set_sc_create_callback(dev->channel, netvsc_sc_open);
 
 	init_packet = &net_device->channel_init_pkt;
@@ -1242,15 +1240,19 @@ int rndis_filter_device_add(struct hv_device *dev,
 	if (ret)
 		goto out;
 
+	wait_for_completion(&net_device->channel_init_wait);
 	if (init_packet->msg.v5_msg.subchn_comp.status != NVSP_STAT_SUCCESS) {
 		ret = -ENODEV;
 		goto out;
 	}
-	wait_for_completion(&net_device->channel_init_wait);
 
 	net_device->num_chn = 1 +
 		init_packet->msg.v5_msg.subchn_comp.num_subchannels;
 
+	/* wait for all sub channels to open */
+	wait_event(net_device->subchan_open,
+		   atomic_read(&net_device->open_chn) == net_device->num_chn);
+
 	/* ignore failues from setting rss parameters, still have channels */
 	rndis_filter_set_rss_param(rndis_device, netvsc_hash_key,
 				   net_device->num_chn);