1 files changed, 45 insertions, 16 deletions

diff --git a/drivers/net/niu.c b/drivers/net/niu.c
index 2541321bad82..9fb59d3f9c92 100644
--- a/drivers/net/niu.c
+++ b/drivers/net/niu.c
@@ -4489,6 +4489,9 @@ static int niu_alloc_channels(struct niu *np)
 {
 	struct niu_parent *parent = np->parent;
 	int first_rx_channel, first_tx_channel;
+	int num_rx_rings, num_tx_rings;
+	struct rx_ring_info *rx_rings;
+	struct tx_ring_info *tx_rings;
 	int i, port, err;
 
 	port = np->port;
@@ -4498,18 +4501,21 @@ static int niu_alloc_channels(struct niu *np)
 		first_tx_channel += parent->txchan_per_port[i];
 	}
 
-	np->num_rx_rings = parent->rxchan_per_port[port];
-	np->num_tx_rings = parent->txchan_per_port[port];
+	num_rx_rings = parent->rxchan_per_port[port];
+	num_tx_rings = parent->txchan_per_port[port];
 
-	netif_set_real_num_rx_queues(np->dev, np->num_rx_rings);
-	netif_set_real_num_tx_queues(np->dev, np->num_tx_rings);
-
-	np->rx_rings = kcalloc(np->num_rx_rings, sizeof(struct rx_ring_info),
-			       GFP_KERNEL);
+	rx_rings = kcalloc(num_rx_rings, sizeof(struct rx_ring_info),
+			   GFP_KERNEL);
 	err = -ENOMEM;
-	if (!np->rx_rings)
+	if (!rx_rings)
 		goto out_err;
 
+	np->num_rx_rings = num_rx_rings;
+	smp_wmb();
+	np->rx_rings = rx_rings;
+
+	netif_set_real_num_rx_queues(np->dev, num_rx_rings);
+
 	for (i = 0; i < np->num_rx_rings; i++) {
 		struct rx_ring_info *rp = &np->rx_rings[i];
 
@@ -4538,12 +4544,18 @@ static int niu_alloc_channels(struct niu *np)
 			return err;
 	}
 
-	np->tx_rings = kcalloc(np->num_tx_rings, sizeof(struct tx_ring_info),
-			       GFP_KERNEL);
+	tx_rings = kcalloc(num_tx_rings, sizeof(struct tx_ring_info),
+			   GFP_KERNEL);
 	err = -ENOMEM;
-	if (!np->tx_rings)
+	if (!tx_rings)
 		goto out_err;
 
+	np->num_tx_rings = num_tx_rings;
+	smp_wmb();
+	np->tx_rings = tx_rings;
+
+	netif_set_real_num_tx_queues(np->dev, num_tx_rings);
+
 	for (i = 0; i < np->num_tx_rings; i++) {
 		struct tx_ring_info *rp = &np->tx_rings[i];
 
@@ -6246,11 +6258,17 @@ static void niu_sync_mac_stats(struct niu *np)
 static void niu_get_rx_stats(struct niu *np)
 {
 	unsigned long pkts, dropped, errors, bytes;
+	struct rx_ring_info *rx_rings;
 	int i;
 
 	pkts = dropped = errors = bytes = 0;
+
+	rx_rings = ACCESS_ONCE(np->rx_rings);
+	if (!rx_rings)
+		goto no_rings;
+
 	for (i = 0; i < np->num_rx_rings; i++) {
-		struct rx_ring_info *rp = &np->rx_rings[i];
+		struct rx_ring_info *rp = &rx_rings[i];
 
 		niu_sync_rx_discard_stats(np, rp, 0);
 
@@ -6259,6 +6277,8 @@ static void niu_get_rx_stats(struct niu *np)
 		dropped += rp->rx_dropped;
 		errors += rp->rx_errors;
 	}
+
+no_rings:
 	np->dev->stats.rx_packets = pkts;
 	np->dev->stats.rx_bytes = bytes;
 	np->dev->stats.rx_dropped = dropped;
@@ -6268,16 +6288,24 @@ static void niu_get_rx_stats(struct niu *np)
 static void niu_get_tx_stats(struct niu *np)
 {
 	unsigned long pkts, errors, bytes;
+	struct tx_ring_info *tx_rings;
 	int i;
 
 	pkts = errors = bytes = 0;
+
+	tx_rings = ACCESS_ONCE(np->tx_rings);
+	if (!tx_rings)
+		goto no_rings;
+
 	for (i = 0; i < np->num_tx_rings; i++) {
-		struct tx_ring_info *rp = &np->tx_rings[i];
+		struct tx_ring_info *rp = &tx_rings[i];
 
 		pkts += rp->tx_packets;
 		bytes += rp->tx_bytes;
 		errors += rp->tx_errors;
 	}
+
+no_rings:
 	np->dev->stats.tx_packets = pkts;
 	np->dev->stats.tx_bytes = bytes;
 	np->dev->stats.tx_errors = errors;
@@ -6287,9 +6315,10 @@ static struct net_device_stats *niu_get_stats(struct net_device *dev)
 {
 	struct niu *np = netdev_priv(dev);
 
-	niu_get_rx_stats(np);
-	niu_get_tx_stats(np);
-
+	if (netif_running(dev)) {
+		niu_get_rx_stats(np);
+		niu_get_tx_stats(np);
+	}
 	return &dev->stats;
 }