r8169: fix vlan tag read ordering.

commit ce11ff5e5963e441feb591e76278528f876c332d upstream.

Control of receive descriptor must not be returned to ethernet chipset
before vlan tag processing is done.

VLAN tag receive word is now reset both in normal and error path.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Spotted-by: Timo Teras <timo.teras@iki.fi>
Cc: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index dd037dda7855293a7950966ed24e664614f16441..cf2038891b5fa32c3ed4a3cc45c0e8bd73b3c3e7 100644 (file)
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -1690,8 +1690,6 @@ static void rtl8169_rx_vlan_tag(struct RxDesc *desc, struct sk_buff *skb)
 
        if (opts2 & RxVlanTag)
                __vlan_hwaccel_put_tag(skb, swab16(opts2 & 0xffff));
-
-       desc->opts2 = 0;
 }
 
 static int rtl8169_gset_tbi(struct net_device *dev, struct ethtool_cmd *cmd)
@@ -5434,8 +5432,6 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp, u32 budget
                            !(status & (RxRWT | RxFOVF)) &&
                            (dev->features & NETIF_F_RXALL))
                                goto process_pkt;
-
-                       rtl8169_mark_to_asic(desc, rx_buf_sz);
                } else {
                        struct sk_buff *skb;
                        dma_addr_t addr;
@@ -5456,16 +5452,14 @@ process_pkt:
                        if (unlikely(rtl8169_fragmented_frame(status))) {
                                dev->stats.rx_dropped++;
                                dev->stats.rx_length_errors++;
-                               rtl8169_mark_to_asic(desc, rx_buf_sz);
-                               continue;
+                               goto release_descriptor;
                        }
 
                        skb = rtl8169_try_rx_copy(tp->Rx_databuff[entry],
                                                  tp, pkt_size, addr);
-                       rtl8169_mark_to_asic(desc, rx_buf_sz);
                        if (!skb) {
                                dev->stats.rx_dropped++;
-                               continue;
+                               goto release_descriptor;
                        }
 
                        rtl8169_rx_csum(skb, status);
@@ -5481,6 +5475,10 @@ process_pkt:
                        tp->rx_stats.bytes += pkt_size;
                        u64_stats_update_end(&tp->rx_stats.syncp);
                }
+release_descriptor:
+               desc->opts2 = 0;
+               wmb();
+               rtl8169_mark_to_asic(desc, rx_buf_sz);
        }
 
        count = cur_rx - tp->cur_rx;