Merge 4.4.120 into android-4.4

Changes in 4.4.120
	hrtimer: Ensure POSIX compliance (relative CLOCK_REALTIME hrtimers)
	f2fs: fix a bug caused by NULL extent tree
	mtd: nand: gpmi: Fix failure when a erased page has a bitflip at BBM
	ipv6: icmp6: Allow icmp messages to be looped back
	ARM: 8731/1: Fix csum_partial_copy_from_user() stack mismatch
	sget(): handle failures of register_shrinker()
	drm/nouveau/pci: do a msi rearm on init
	spi: atmel: fixed spin_lock usage inside atmel_spi_remove
	net: arc_emac: fix arc_emac_rx() error paths
	scsi: storvsc: Fix scsi_cmd error assignments in storvsc_handle_error
	ARM: dts: ls1021a: fix incorrect clock references
	lib/mpi: Fix umul_ppmm() for MIPS64r6
	tg3: Add workaround to restrict 5762 MRRS to 2048
	tg3: Enable PHY reset in MTU change path for 5720
	bnx2x: Improve reliability in case of nested PCI errors
	led: core: Fix brightness setting when setting delay_off=0
	s390/dasd: fix wrongly assigned configuration data
	IB/mlx4: Fix mlx4_ib_alloc_mr error flow
	IB/ipoib: Fix race condition in neigh creation
	xfs: quota: fix missed destroy of qi_tree_lock
	xfs: quota: check result of register_shrinker()
	e1000: fix disabling already-disabled warning
	drm/ttm: check the return value of kzalloc
	mac80211: mesh: drop frames appearing to be from us
	can: flex_can: Correct the checking for frame length in flexcan_start_xmit()
	bnxt_en: Fix the 'Invalid VF' id check in bnxt_vf_ndo_prep routine.
	xen-netfront: enable device after manual module load
	mdio-sun4i: Fix a memory leak
	SolutionEngine771x: fix Ether platform data
	xen/gntdev: Fix off-by-one error when unmapping with holes
	xen/gntdev: Fix partial gntdev_mmap() cleanup
	sctp: make use of pre-calculated len
	net: gianfar_ptp: move set_fipers() to spinlock protecting area
	MIPS: Implement __multi3 for GCC7 MIPS64r6 builds
	Linux 4.4.120

Change-Id: Ie363d2e798f7bbe76e728c995e605af94667dfe5
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

1 files changed, 31 insertions, 22 deletions

diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index abe1eabc0171..9cc5daed13ed 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -250,39 +250,48 @@ static int arc_emac_rx(struct net_device *ndev, int budget)
 			continue;
 		}
 
-		pktlen = info & LEN_MASK;
-		stats->rx_packets++;
-		stats->rx_bytes += pktlen;
-		skb = rx_buff->skb;
-		skb_put(skb, pktlen);
-		skb->dev = ndev;
-		skb->protocol = eth_type_trans(skb, ndev);
-
-		dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr),
-				 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE);
-
-		/* Prepare the BD for next cycle */
-		rx_buff->skb = netdev_alloc_skb_ip_align(ndev,
-							 EMAC_BUFFER_SIZE);
-		if (unlikely(!rx_buff->skb)) {
+		/* Prepare the BD for next cycle. netif_receive_skb()
+		 * only if new skb was allocated and mapped to avoid holes
+		 * in the RX fifo.
+		 */
+		skb = netdev_alloc_skb_ip_align(ndev, EMAC_BUFFER_SIZE);
+		if (unlikely(!skb)) {
+			if (net_ratelimit())
+				netdev_err(ndev, "cannot allocate skb\n");
+			/* Return ownership to EMAC */
+			rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
 			stats->rx_errors++;
-			/* Because receive_skb is below, increment rx_dropped */
 			stats->rx_dropped++;
 			continue;
 		}
 
-		/* receive_skb only if new skb was allocated to avoid holes */
-		netif_receive_skb(skb);
-
-		addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data,
+		addr = dma_map_single(&ndev->dev, (void *)skb->data,
 				      EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
 		if (dma_mapping_error(&ndev->dev, addr)) {
 			if (net_ratelimit())
-				netdev_err(ndev, "cannot dma map\n");
-			dev_kfree_skb(rx_buff->skb);
+				netdev_err(ndev, "cannot map dma buffer\n");
+			dev_kfree_skb(skb);
+			/* Return ownership to EMAC */
+			rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
 			stats->rx_errors++;
+			stats->rx_dropped++;
 			continue;
 		}
+
+		/* unmap previosly mapped skb */
+		dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr),
+				 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE);
+
+		pktlen = info & LEN_MASK;
+		stats->rx_packets++;
+		stats->rx_bytes += pktlen;
+		skb_put(rx_buff->skb, pktlen);
+		rx_buff->skb->dev = ndev;
+		rx_buff->skb->protocol = eth_type_trans(rx_buff->skb, ndev);
+
+		netif_receive_skb(rx_buff->skb);
+
+		rx_buff->skb = skb;
 		dma_unmap_addr_set(rx_buff, addr, addr);
 		dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);