e1000: add dummy allocator to fix race condition between mtu change and netpoll

[firefly-linux-kernel-4.4.55.git] / drivers / net / ethernet / intel / e1000 / e1000_main.c

diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index 7f997d36948f3e59621b3698b1a43b36166ecf93..73c98d34fa1f9b7238b895f7900a6d0a11d3faa9 100644 (file)
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -144,6 +144,11 @@ static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
 static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
                                     struct e1000_rx_ring *rx_ring,
                                     int *work_done, int work_to_do);
+static void e1000_alloc_dummy_rx_buffers(struct e1000_adapter *adapter,
+                                        struct e1000_rx_ring *rx_ring,
+                                        int cleaned_count)
+{
+}
 static void e1000_alloc_rx_buffers(struct e1000_adapter *adapter,
                                   struct e1000_rx_ring *rx_ring,
                                   int cleaned_count);
@@ -516,6 +521,7 @@ void e1000_down(struct e1000_adapter *adapter)
        struct net_device *netdev = adapter->netdev;
        u32 rctl, tctl;
 
+       netif_carrier_off(netdev);
 
        /* disable receives in the hardware */
        rctl = er32(RCTL);
@@ -544,7 +550,6 @@ void e1000_down(struct e1000_adapter *adapter)
 
        adapter->link_speed = 0;
        adapter->link_duplex = 0;
-       netif_carrier_off(netdev);
 
        e1000_reset(adapter);
        e1000_clean_all_tx_rings(adapter);
@@ -3552,8 +3557,11 @@ static int e1000_change_mtu(struct net_device *netdev, int new_mtu)
                msleep(1);
        /* e1000_down has a dependency on max_frame_size */
        hw->max_frame_size = max_frame;
-       if (netif_running(netdev))
+       if (netif_running(netdev)) {
+               /* prevent buffers from being reallocated */
+               adapter->alloc_rx_buf = e1000_alloc_dummy_rx_buffers;
                e1000_down(adapter);
+       }
 
        /* NOTE: netdev_alloc_skb reserves 16 bytes, and typically NET_IP_ALIGN
         * means we reserve 2 more, this pushes us to allocate from the next