Merge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net-queue

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates 2017-10-26

This series contains fixes to e1000, igb, ixgbe and i40e.

Vincenzo Maffione fixes a potential race condition which would result in
the interface being up but transmits are disabled in the hardware.

Colin Ian King fixes a possible NULL pointer dereference in e1000, which
was found by Coverity.

Jean-Philippe Brucker fixes a possible kernel panic when a driver cannot
map a transmit buffer, which is caused by an erroneous test.

Alex provides a fix for ixgbe, which is a partial revert of the commit
ffed21bcee7a ("ixgbe: Don't bother clearing buffer memory for descriptor rings")
because the previous commit messed up the exception handling path by
adding the count back in when we did not need to.  Also fixed a typo,
where the transmit ITR setting was being used to determine if we were
using adaptive receive interrupt moderation or not.  Lastly, fixed a
memory leak by including programming descriptors in the cleaned count.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 22 insertions, 21 deletions

diff --git a/drivers/net/ethernet/intel/e1000/e1000_ethtool.c b/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
index ec8aa4562cc9..3b3983a1ffbb 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
@@ -1824,11 +1824,12 @@ static void e1000_get_ethtool_stats(struct net_device *netdev,
 {
 	struct e1000_adapter *adapter = netdev_priv(netdev);
 	int i;
-	char *p = NULL;
 	const struct e1000_stats *stat = e1000_gstrings_stats;
 
 	e1000_update_stats(adapter);
-	for (i = 0; i < E1000_GLOBAL_STATS_LEN; i++) {
+	for (i = 0; i < E1000_GLOBAL_STATS_LEN; i++, stat++) {
+		char *p;
+
 		switch (stat->type) {
 		case NETDEV_STATS:
 			p = (char *)netdev + stat->stat_offset;
@@ -1839,15 +1840,13 @@ static void e1000_get_ethtool_stats(struct net_device *netdev,
 		default:
 			WARN_ONCE(1, "Invalid E1000 stat type: %u index %d\n",
 				  stat->type, i);
-			break;
+			continue;
 		}
 
 		if (stat->sizeof_stat == sizeof(u64))
 			data[i] = *(u64 *)p;
 		else
 			data[i] = *(u32 *)p;
-
-		stat++;
 	}
 /* BUG_ON(i != E1000_STATS_LEN); */
 }
diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index 98375e1e1185..1982f7917a8d 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -520,8 +520,6 @@ 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);
 	ew32(RCTL, rctl & ~E1000_RCTL_EN);
@@ -537,6 +535,15 @@ void e1000_down(struct e1000_adapter *adapter)
 	E1000_WRITE_FLUSH();
 	msleep(10);
 
+	/* Set the carrier off after transmits have been disabled in the
+	 * hardware, to avoid race conditions with e1000_watchdog() (which
+	 * may be running concurrently to us, checking for the carrier
+	 * bit to decide whether it should enable transmits again). Such
+	 * a race condition would result into transmission being disabled
+	 * in the hardware until the next IFF_DOWN+IFF_UP cycle.
+	 */
+	netif_carrier_off(netdev);
+
 	napi_disable(&adapter->napi);
 
 	e1000_irq_disable(adapter);
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 2756131495f0..120c68f78951 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2102,6 +2102,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 
 		if (unlikely(i40e_rx_is_programming_status(qword))) {
 			i40e_clean_programming_status(rx_ring, rx_desc, qword);
+			cleaned_count++;
 			continue;
 		}
 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
@@ -2269,7 +2270,7 @@ static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
 		goto enable_int;
 	}
 
-	if (ITR_IS_DYNAMIC(tx_itr_setting)) {
+	if (ITR_IS_DYNAMIC(rx_itr_setting)) {
 		rx = i40e_set_new_dynamic_itr(&q_vector->rx);
 		rxval = i40e_buildreg_itr(I40E_RX_ITR, q_vector->rx.itr);
 	}
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index fd4a46b03cc8..ea69af267d63 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -5326,7 +5326,7 @@ dma_error:
 				       DMA_TO_DEVICE);
 		dma_unmap_len_set(tx_buffer, len, 0);
 
-		if (i--)
+		if (i-- == 0)
 			i += tx_ring->count;
 		tx_buffer = &tx_ring->tx_buffer_info[i];
 	}
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 4d76afd13868..6d5f31e94358 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -8020,29 +8020,23 @@ static int ixgbe_tx_map(struct ixgbe_ring *tx_ring,
 	return 0;
 dma_error:
 	dev_err(tx_ring->dev, "TX DMA map failed\n");
-	tx_buffer = &tx_ring->tx_buffer_info[i];
 
 	/* clear dma mappings for failed tx_buffer_info map */
-	while (tx_buffer != first) {
+	for (;;) {
+		tx_buffer = &tx_ring->tx_buffer_info[i];
 		if (dma_unmap_len(tx_buffer, len))
 			dma_unmap_page(tx_ring->dev,
 				       dma_unmap_addr(tx_buffer, dma),
 				       dma_unmap_len(tx_buffer, len),
 				       DMA_TO_DEVICE);
 		dma_unmap_len_set(tx_buffer, len, 0);
-
-		if (i--)
+		if (tx_buffer == first)
+			break;
+		if (i == 0)
 			i += tx_ring->count;
-		tx_buffer = &tx_ring->tx_buffer_info[i];
+		i--;
 	}
 
-	if (dma_unmap_len(tx_buffer, len))
-		dma_unmap_single(tx_ring->dev,
-				 dma_unmap_addr(tx_buffer, dma),
-				 dma_unmap_len(tx_buffer, len),
-				 DMA_TO_DEVICE);
-	dma_unmap_len_set(tx_buffer, len, 0);
-
 	dev_kfree_skb_any(first->skb);
 	first->skb = NULL;