ehea: Fix a checksum issue on the receive path

Currently we set all skbs with CHECKSUM_UNNECESSARY, even
those whose protocol we don't know. This patch just
add the CHECKSUM_COMPLETE tag for non TCP/UDP packets.

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ehea/ehea_main.c

@@ -533,8 +533,15 @@ static inline void ehea_fill_skb(struct net_device *dev,
 	int length = cqe->num_bytes_transfered - 4;	/*remove CRC */
 
 	skb_put(skb, length);
-	skb->ip_summed = CHECKSUM_UNNECESSARY;
 	skb->protocol = eth_type_trans(skb, dev);
+
+	/* The packet was not an IPV4 packet so a complemented checksum was
+	   calculated. The value is found in the Internet Checksum field. */
+	if (cqe->status & EHEA_CQE_BLIND_CKSUM) {
+		skb->ip_summed = CHECKSUM_COMPLETE;
+		skb->csum = csum_unfold(~cqe->inet_checksum_value);
+	} else
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
 }
 
 static inline struct sk_buff *get_skb_by_index(struct sk_buff **skb_array,

drivers/net/ehea/ehea_qmr.h

@@ -150,6 +150,7 @@ struct ehea_rwqe {
 #define EHEA_CQE_TYPE_RQ           0x60
 #define EHEA_CQE_STAT_ERR_MASK     0x700F
 #define EHEA_CQE_STAT_FAT_ERR_MASK 0xF
+#define EHEA_CQE_BLIND_CKSUM       0x8000
 #define EHEA_CQE_STAT_ERR_TCP      0x4000
 #define EHEA_CQE_STAT_ERR_IP       0x2000
 #define EHEA_CQE_STAT_ERR_CRC      0x1000