[PATCH 4.9 197/271] net: sonic: return NETDEV_TX_OK if failed to map buffer

From: Greg Kroah-Hartman
Date: Tue Jan 28 2020 - 09:35:48 EST


From: Mao Wenan <maowenan@xxxxxxxxxx>

[ Upstream commit 6e1cdedcf0362fed3aedfe051d46bd7ee2a85fe1 ]

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@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/natsemi/sonic.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c
index 23821540ab078..11f472fd5d477 100644
--- a/drivers/net/ethernet/natsemi/sonic.c
+++ b/drivers/net/ethernet/natsemi/sonic.c
@@ -221,9 +221,9 @@ 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 */
--
2.20.1