net: fix race on decreasing number of TX queues

[pandora-kernel.git] / net / core / dev.c

diff --git a/net/core/dev.c b/net/core/dev.c
index ec29958..56a6ad8 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1750,8 +1750,11 @@ static void netif_setup_tc(struct net_device *dev, unsigned int txq)
  */
 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
 {
+       bool disabling;
        int rc;
 
+       disabling = txq < dev->real_num_tx_queues;
+
        if (txq < 1 || txq > dev->num_tx_queues)
                return -EINVAL;
 
@@ -1767,11 +1770,16 @@ int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
                if (dev->num_tc)
                        netif_setup_tc(dev, txq);
 
-               if (txq < dev->real_num_tx_queues)
+               dev->real_num_tx_queues = txq;
+
+               if (disabling) {
+                       synchronize_net();
                        qdisc_reset_all_tx_gt(dev, txq);
+               }
+       } else {
+               dev->real_num_tx_queues = txq;
        }
 
-       dev->real_num_tx_queues = txq;
        return 0;
 }
 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
@@ -1918,7 +1926,7 @@ int skb_checksum_help(struct sk_buff *skb)
                        goto out;
        }
 
-       *(__sum16 *)(skb->data + offset) = csum_fold(csum);
+       *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0;
 out_set_summed:
        skb->ip_summed = CHECKSUM_NONE;
 out:
@@ -3627,7 +3635,9 @@ void skb_gro_reset_offset(struct sk_buff *skb)
            !PageHighMem(skb_frag_page(&skb_shinfo(skb)->frags[0]))) {
                NAPI_GRO_CB(skb)->frag0 =
                        skb_frag_address(&skb_shinfo(skb)->frags[0]);
-               NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(&skb_shinfo(skb)->frags[0]);
+               NAPI_GRO_CB(skb)->frag0_len = min_t(unsigned int,
+                                                   skb_frag_size(&skb_shinfo(skb)->frags[0]),
+                                                   skb->end - skb->tail);
        }
 }
 EXPORT_SYMBOL(skb_gro_reset_offset);
@@ -5940,7 +5950,7 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
        } else {
                netdev_stats_to_stats64(storage, &dev->stats);
        }
-       storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
+       storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped);
        return storage;
 }
 EXPORT_SYMBOL(dev_get_stats);