s390/qeth: let isolation mode override HW offload restrictions

When a device is configured with ISOLATION_MODE_FWD, traffic never goes
through the internal switch. Don't apply the offload restrictions in
this case.

Fixes: c619e9a6 ("s390/qeth: don't use restricted offloads for local traffic")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/s390/net/qeth_core_main.c

@@ -6837,9 +6837,11 @@ netdev_features_t qeth_features_check(struct sk_buff *skb,
 				      struct net_device *dev,
 				      netdev_features_t features)
 {
-	/* Traffic with local next-hop is not eligible for some offloads: */
-	if (skb->ip_summed == CHECKSUM_PARTIAL) {
 	struct qeth_card *card = dev->ml_priv;
+
+	/* Traffic with local next-hop is not eligible for some offloads: */
+	if (skb->ip_summed == CHECKSUM_PARTIAL &&
+	    card->options.isolation != ISOLATION_MODE_FWD) {
 		netdev_features_t restricted = 0;
 
 		if (skb_is_gso(skb) && !netif_needs_gso(skb, features))