Merge tag 'v3.9-rc3' into drm-intel-next-queued

Backmerge so that I can merge Imre Deak's coalesced sg entries fixes,
which depend upon the new for_each_sg_page introduce in

commit a321e91b6d73ed011ffceed384c40d2785cf723b
Author: Imre Deak <imre.deak@intel.com>
Date:   Wed Feb 27 17:02:56 2013 -0800

    lib/scatterlist: add simple page iterator

The merge itself is just two trivial conflicts:

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 30 insertions, 10 deletions

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index f34b2ebee815..51f3192f3931 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -380,6 +380,12 @@ static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 	unsigned long		lockflags;
 	size_t			size = dev->rx_urb_size;
 
+	/* prevent rx skb allocation when error ratio is high */
+	if (test_bit(EVENT_RX_KILL, &dev->flags)) {
+		usb_free_urb(urb);
+		return -ENOLINK;
+	}
+
 	skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
 	if (!skb) {
 		netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
@@ -539,6 +545,17 @@ block:
 		break;
 	}
 
+	/* stop rx if packet error rate is high */
+	if (++dev->pkt_cnt > 30) {
+		dev->pkt_cnt = 0;
+		dev->pkt_err = 0;
+	} else {
+		if (state == rx_cleanup)
+			dev->pkt_err++;
+		if (dev->pkt_err > 20)
+			set_bit(EVENT_RX_KILL, &dev->flags);
+	}
+
 	state = defer_bh(dev, skb, &dev->rxq, state);
 
 	if (urb) {
@@ -791,6 +808,11 @@ int usbnet_open (struct net_device *net)
 		   (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 		   "simple");
 
+	/* reset rx error state */
+	dev->pkt_cnt = 0;
+	dev->pkt_err = 0;
+	clear_bit(EVENT_RX_KILL, &dev->flags);
+
 	// delay posting reads until we're fully open
 	tasklet_schedule (&dev->bh);
 	if (info->manage_power) {
@@ -1103,13 +1125,11 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
 	if (info->tx_fixup) {
 		skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
 		if (!skb) {
-			if (netif_msg_tx_err(dev)) {
-				netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
-				goto drop;
-			} else {
-				/* cdc_ncm collected packet; waits for more */
+			/* packet collected; minidriver waiting for more */
+			if (info->flags & FLAG_MULTI_PACKET)
 				goto not_drop;
-			}
+			netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
+			goto drop;
 		}
 	}
 	length = skb->len;
@@ -1254,6 +1274,9 @@ static void usbnet_bh (unsigned long param)
 		}
 	}
 
+	/* restart RX again after disabling due to high error rate */
+	clear_bit(EVENT_RX_KILL, &dev->flags);
+
 	// waiting for all pending urbs to complete?
 	if (dev->wait) {
 		if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
@@ -1790,11 +1813,8 @@ int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
 	}
 
 	req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
-	if (!req) {
-		netdev_err(dev->net, "Failed to allocate memory for %s\n",
-			   __func__);
+	if (!req)
 		goto fail_free_buf;
-	}
 
 	req->bRequestType = reqtype;
 	req->bRequest = cmd;