From: Sudarsana Reddy Kalluru <skalluru@marvell.com>
Date: Thu, 7 Mar 2019 07:56:35 -0800
Subject: qede: Fix internal loopback failure with jumbo mtu configuration
Patch-mainline: v5.1-rc1
Git-commit: b89869da2db916914f6a2c7ab14183c8aef23d97
References: bsc#1136460 jsc#SLE-4691 bsc#1136461 jsc#SLE-4692

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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/qlogic/qede/qede_ethtool.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- 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(st
 	/* 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) {