diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 1a5ad143be40..ca5a2c5675c5 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -621,7 +621,7 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 	struct net *net = tunnel->net;
 	struct net_device *tdev;    /* Device to other host */
 	struct ipv6hdr  *ipv6h;     /* Our new IP header */
-	unsigned int max_headroom = 0; /* The extra header space needed */
+	unsigned int min_headroom = 0; /* The extra header space needed */
 	int    gre_hlen;
 	struct ipv6_tel_txoption opt;
 	int    mtu;
@@ -629,7 +629,6 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 	struct net_device_stats *stats = &tunnel->dev->stats;
 	int err = -1;
 	u8 proto;
-	struct sk_buff *new_skb;
 	__be16 protocol;
 
 	if (dev->type == ARPHRD_ETHER)
@@ -672,14 +671,14 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 
 	mtu = dst_mtu(dst) - sizeof(*ipv6h);
 	if (encap_limit >= 0) {
-		max_headroom += 8;
+		min_headroom += 8;
 		mtu -= 8;
 	}
 	if (mtu < IPV6_MIN_MTU)
 		mtu = IPV6_MIN_MTU;
 	if (skb_dst(skb))
 		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
-	if (skb->len > mtu) {
+	if (skb->len > mtu && !skb_is_gso(skb)) {
 		*pmtu = mtu;
 		err = -EMSGSIZE;
 		goto tx_err_dst_release;
@@ -697,20 +696,19 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 
 	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
 
-	max_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len;
+	min_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len;
 
-	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
-	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
-		new_skb = skb_realloc_headroom(skb, max_headroom);
-		if (max_headroom > dev->needed_headroom)
-			dev->needed_headroom = max_headroom;
-		if (!new_skb)
+	if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
+		int head_delta = SKB_DATA_ALIGN(min_headroom -
+						skb_headroom(skb) +
+						16);
+
+		err = pskb_expand_head(skb, max_t(int, head_delta, 0),
+				       0, GFP_ATOMIC);
+		if (min_headroom > dev->needed_headroom)
+			dev->needed_headroom = min_headroom;
+		if (unlikely(err))
 			goto tx_err_dst_release;
-
-		if (skb->sk)
-			skb_set_owner_w(new_skb, skb->sk);
-		consume_skb(skb);
-		skb = new_skb;
 	}
 
 	if (!fl6->flowi6_mark && ndst)
@@ -723,10 +721,11 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 		ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
 	}
 
-	if (likely(!skb->encapsulation)) {
-		skb_reset_inner_headers(skb);
-		skb->encapsulation = 1;
-	}
+	err = iptunnel_handle_offloads(skb,
+				       (tunnel->parms.o_flags & GRE_CSUM) ?
+				       SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
+	if (err)
+		goto tx_err_dst_release;
 
 	skb_push(skb, gre_hlen);
 	skb_reset_network_header(skb);
@@ -760,7 +759,9 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 			*ptr = tunnel->parms.o_key;
 			ptr--;
 		}
-		if (tunnel->parms.o_flags&GRE_CSUM) {
+		if ((tunnel->parms.o_flags & GRE_CSUM) &&
+		    !(skb_shinfo(skb)->gso_type &
+		      (SKB_GSO_GRE | SKB_GSO_GRE_CSUM))) {
 			*ptr = 0;
 			*(__sum16 *)ptr = gre6_checksum(skb);
 		}
@@ -1559,9 +1560,18 @@ static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
 	dev->features		|= GRE6_FEATURES;
 	dev->hw_features	|= GRE6_FEATURES;
 
-	/* Can use a lockless transmit, unless we generate output sequences */
-	if (!(nt->parms.o_flags & GRE_SEQ))
+	if (!(nt->parms.o_flags & GRE_SEQ)) {
+		/* TCP segmentation offload is not supported when we
+		 * generate output sequences.
+		 */
+		dev->features    |= NETIF_F_GSO_SOFTWARE;
+		dev->hw_features |= NETIF_F_GSO_SOFTWARE;
+
+		/* Can use a lockless transmit, unless we generate
+		 * output sequences
+		 */
 		dev->features |= NETIF_F_LLTX;
+	}
 
 	err = register_netdevice(dev);
 	if (err)