release/5.2.38/net-sonic-return-NETDEV_TX_OK-if-failed-to-map-buffe.patch

From 7426b0a6558af06af2996bbef149225e5ecd2da0 Mon Sep 17 00:00:00 2001
From: Mao Wenan <maowenan@huawei.com>
Date: Thu, 5 Sep 2019 09:57:12 +0800
Subject: [PATCH] net: sonic: return NETDEV_TX_OK if failed to map buffer

commit 6e1cdedcf0362fed3aedfe051d46bd7ee2a85fe1 upstream.

NETDEV_TX_BUSY really should only be used by drivers that call
netif_tx_stop_queue() at the wrong moment. If dma_map_single() is
failed to map tx DMA buffer, it might trigger an infinite loop.
This patch use NETDEV_TX_OK instead of NETDEV_TX_BUSY, and change
printk to pr_err_ratelimited.

Fixes: d9fb9f384292 ("*sonic/natsemi/ns83829: Move the National Semi-conductor drivers")
Signed-off-by: Mao Wenan <maowenan@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c
index d0a01e8f000a..18fd62fbfb64 100644
--- a/drivers/net/ethernet/natsemi/sonic.c
+++ b/drivers/net/ethernet/natsemi/sonic.c
@@ -232,9 +232,9 @@ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev)
 
 	laddr = dma_map_single(lp->device, skb->data, length, DMA_TO_DEVICE);
 	if (!laddr) {
-		printk(KERN_ERR "%s: failed to map tx DMA buffer.\n", dev->name);
+		pr_err_ratelimited("%s: failed to map tx DMA buffer.\n", dev->name);
 		dev_kfree_skb(skb);
-		return NETDEV_TX_BUSY;
+		return NETDEV_TX_OK;
 	}
 
 	sonic_tda_put(dev, entry, SONIC_TD_STATUS, 0);       /* clear status */
-- 
2.7.4