qede: Fix internal loopback failure with jumbo mtu configuration

Driver uses port-mtu as packet-size for the loopback traffic. This patch
limits the max packet size to 1.5K to avoid data being split over multiple
buffer descriptors (BDs) in cases where MTU > PAGE_SIZE.

Signed-off-by: Sudarsana Reddy Kalluru <skalluru@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/qlogic/qede/qede_ethtool.c b/drivers/net/ethernet/qlogic/qede/qede_ethtool.c
index c6238083e89833460b6358cdc1640133cc7d1202..b4c8949933f161521c1a544ce8c738c35ec381f4 100644 (file)
--- a/drivers/net/ethernet/qlogic/qede/qede_ethtool.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_ethtool.c
@@ -1663,8 +1663,11 @@ static int qede_selftest_run_loopback(struct qede_dev *edev, u32 loopback_mode)
        /* Wait for loopback configuration to apply */
        msleep_interruptible(500);
 
-       /* prepare the loopback packet */
-       pkt_size = edev->ndev->mtu + ETH_HLEN;
+       /* Setting max packet size to 1.5K to avoid data being split over
+        * multiple BDs in cases where MTU > PAGE_SIZE.
+        */
+       pkt_size = (((edev->ndev->mtu < ETH_DATA_LEN) ?
+                    edev->ndev->mtu : ETH_DATA_LEN) + ETH_HLEN);
 
        skb = netdev_alloc_skb(edev->ndev, pkt_size);
        if (!skb) {