igb: Fix error of RX network flow classification

From: Gangfeng Huang <[email protected]>

After add an ethertype filter, if user change the adapter speed several times, the error "ethtool -N: etype filters are all used" is reported by igb driver.

In older patch, function igb_nfc_filter_exit() and igb_nfc_filter_restore() is not paried. igb_nfc_filter_restore() exist in igb_up(), but function igb_nfc_filter_exit() is exist in __igb_close(). In the process of speed changing, only igb_nfc_filter_restore() is called, it will take a position of ethertype bitmap.

Reproduce steps:
Step 1: Add a etype filter by ethtool
$ethtool -N eth0 flow-type ether proto 0x88F8 action 1
Step 2: Change the adapter speed to 100M/full duplex
$ethtool -s eth0 speed 100 duplex full
Step 3: Change the adapter speed to 1000M/full duplex
ethtool -s eth0 speed 1000 duplex full
Repeat step2 and step3, then dmesg the system log, you can find the error message, add new ethtype filter is also failed.

This fixing is move igb_nfc_filter_exit() from __igb_close() to igb_down() to make igb_nfc_filter_restore()/igb_nfc_filter_exit() is paired.

---
 drivers/net/ethernet/intel/igb/igb_main.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index 8f624af..e01e01a 100644
@@ -1791,6 +1791,8 @@ void igb_down(struct igb_adapter *adapter)
 	wr32(E1000_RCTL, rctl & ~E1000_RCTL_EN);
 	/* flush and sleep below */
 
+	igb_nfc_filter_exit(adapter);
+
 	netif_carrier_off(netdev);
 	netif_tx_stop_all_queues(netdev);
 

@@ -3317,8 +3319,6 @@ static int __igb_close(struct net_device *netdev, bool suspending)
 	igb_down(adapter);
 	igb_free_irq(adapter);
 
-	igb_nfc_filter_exit(adapter);
-
 	igb_free_all_tx_resources(adapter);
 	igb_free_all_rx_resources(adapter);
 

2.7.2

Thank you, this looks much better!