diff --git a/drivers/net/thunderbolt.c b/drivers/net/thunderbolt.c
index 3395dcb0b262..470852f7a64d 100644
--- a/drivers/net/thunderbolt.c
+++ b/drivers/net/thunderbolt.c
@@ -993,12 +993,11 @@ static bool tbnet_xmit_csum_and_map(struct tbnet *net, struct sk_buff *skb,
 		*tucso = ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
 					    ip_hdr(skb)->daddr, 0,
 					    ip_hdr(skb)->protocol, 0);
-	} else if (skb_is_gso_v6(skb)) {
+	} else if (skb_is_gso(skb) && skb_is_gso_v6(skb)) {
 		tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
 		*tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 					  &ipv6_hdr(skb)->daddr, 0,
 					  IPPROTO_TCP, 0);
-		return false;
 	} else if (protocol == htons(ETH_P_IPV6)) {
 		tucso = dest + skb_checksum_start_offset(skb) + skb->csum_offset;
 		*tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,