Merge branch 'big-tcp'

Eric Dumazet says:

====================
tcp: BIG TCP implementation

This series implements BIG TCP as presented in netdev 0x15:

https://netdevconf.info/0x15/session.html?BIG-TCP

Jonathan Corbet made a nice summary: https://lwn.net/Articles/884104/

Standard TSO/GRO packet limit is 64KB

With BIG TCP, we allow bigger TSO/GRO packet sizes for IPv6 traffic.

Note that this feature is by default not enabled, because it might
break some eBPF programs assuming TCP header immediately follows IPv6 header.

While tcpdump recognizes the HBH/Jumbo header, standard pcap filters
are unable to skip over IPv6 extension headers.

Reducing number of packets traversing networking stack usually improves
performance, as shown on this experiment using a 100Gbit NIC, and 4K MTU.

'Standard' performance with current (74KB) limits.
for i in {1..10}; do ./netperf -t TCP_RR -H iroa23  -- -r80000,80000 -O MIN_LATENCY,P90_LATENCY,P99_LATENCY,THROUGHPUT|tail -1; done
77           138          183          8542.19
79           143          178          8215.28
70           117          164          9543.39
80           144          176          8183.71
78           126          155          9108.47
80           146          184          8115.19
71           113          165          9510.96
74           113          164          9518.74
79           137          178          8575.04
73           111          171          9561.73

Now enable BIG TCP on both hosts.

ip link set dev eth0 gro_max_size 185000 gso_max_size 185000
for i in {1..10}; do ./netperf -t TCP_RR -H iroa23  -- -r80000,80000 -O MIN_LATENCY,P90_LATENCY,P99_LATENCY,THROUGHPUT|tail -1; done
57           83           117          13871.38
64           118          155          11432.94
65           116          148          11507.62
60           105          136          12645.15
60           103          135          12760.34
60           102          134          12832.64
62           109          132          10877.68
58           82           115          14052.93
57           83           124          14212.58
57           82           119          14196.01

We see an increase of transactions per second, and lower latencies as well.

v7: adopt unsafe_memcpy() in mlx5 to avoid FORTIFY warnings.

v6: fix a compilation error for CONFIG_IPV6=n in
    "net: allow gso_max_size to exceed 65536", reported by kernel bots.

v5: Replaced two patches (that were adding new attributes) with patches
    from Alexander Duyck. Idea is to reuse existing gso_max_size/gro_max_size

v4: Rebased on top of Jakub series (Merge branch 'tso-gso-limit-split')
    max_tso_size is now family independent.

v3: Fixed a typo in RFC number (Alexander)
    Added Reviewed-by: tags from Tariq on mlx4/mlx5 parts.

v2: Removed the MAX_SKB_FRAGS change, this belongs to a different series.
    Addressed feedback, for Alexander and nvidia folks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

14 files changed, 146 insertions, 40 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index 607a2c90513b..d9547552ceef 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -151,7 +151,8 @@
 #define XGBE_TX_MAX_BUF_SIZE	(0x3fff & ~(64 - 1))
 
 /* Descriptors required for maximum contiguous TSO/GSO packet */
-#define XGBE_TX_MAX_SPLIT	((GSO_MAX_SIZE / XGBE_TX_MAX_BUF_SIZE) + 1)
+#define XGBE_TX_MAX_SPLIT	\
+	((GSO_LEGACY_MAX_SIZE / XGBE_TX_MAX_BUF_SIZE) + 1)
 
 /* Maximum possible descriptors needed for an SKB:
  * - Maximum number of SKB frags
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index c61dc7ae0c05..ca4b93a01034 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -3417,6 +3417,9 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
 	dev->min_mtu = ETH_MIN_MTU;
 	dev->max_mtu = priv->max_mtu;
 
+	/* supports LSOv2 packets. */
+	netif_set_tso_max_size(dev, GSO_MAX_SIZE);
+
 	mdev->pndev[port] = dev;
 	mdev->upper[port] = NULL;
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index f777151d226f..af3b2b59a2a6 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -43,6 +43,7 @@
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/indirect_call_wrapper.h>
+#include <net/ipv6.h>
 
 #include "mlx4_en.h"
 
@@ -634,19 +635,28 @@ static int get_real_size(const struct sk_buff *skb,
 			 struct net_device *dev,
 			 int *lso_header_size,
 			 bool *inline_ok,
-			 void **pfrag)
+			 void **pfrag,
+			 int *hopbyhop)
 {
 	struct mlx4_en_priv *priv = netdev_priv(dev);
 	int real_size;
 
 	if (shinfo->gso_size) {
 		*inline_ok = false;
-		if (skb->encapsulation)
+		*hopbyhop = 0;
+		if (skb->encapsulation) {
 			*lso_header_size = (skb_inner_transport_header(skb) - skb->data) + inner_tcp_hdrlen(skb);
-		else
+		} else {
+			/* Detects large IPV6 TCP packets and prepares for removal of
+			 * HBH header that has been pushed by ip6_xmit(),
+			 * mainly so that tcpdump can dissect them.
+			 */
+			if (ipv6_has_hopopt_jumbo(skb))
+				*hopbyhop = sizeof(struct hop_jumbo_hdr);
 			*lso_header_size = skb_transport_offset(skb) + tcp_hdrlen(skb);
+		}
 		real_size = CTRL_SIZE + shinfo->nr_frags * DS_SIZE +
-			ALIGN(*lso_header_size + 4, DS_SIZE);
+			ALIGN(*lso_header_size - *hopbyhop + 4, DS_SIZE);
 		if (unlikely(*lso_header_size != skb_headlen(skb))) {
 			/* We add a segment for the skb linear buffer only if
 			 * it contains data */
@@ -873,6 +883,7 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 	int desc_size;
 	int real_size;
 	u32 index, bf_index;
+	struct ipv6hdr *h6;
 	__be32 op_own;
 	int lso_header_size;
 	void *fragptr = NULL;
@@ -881,6 +892,7 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 	bool stop_queue;
 	bool inline_ok;
 	u8 data_offset;
+	int hopbyhop;
 	bool bf_ok;
 
 	tx_ind = skb_get_queue_mapping(skb);
@@ -890,7 +902,7 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 		goto tx_drop;
 
 	real_size = get_real_size(skb, shinfo, dev, &lso_header_size,
-				  &inline_ok, &fragptr);
+				  &inline_ok, &fragptr, &hopbyhop);
 	if (unlikely(!real_size))
 		goto tx_drop_count;
 
@@ -943,7 +955,7 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 		data = &tx_desc->data;
 		data_offset = offsetof(struct mlx4_en_tx_desc, data);
 	} else {
-		int lso_align = ALIGN(lso_header_size + 4, DS_SIZE);
+		int lso_align = ALIGN(lso_header_size - hopbyhop + 4, DS_SIZE);
 
 		data = (void *)&tx_desc->lso + lso_align;
 		data_offset = offsetof(struct mlx4_en_tx_desc, lso) + lso_align;
@@ -1008,14 +1020,31 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 			((ring->prod & ring->size) ?
 				cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
 
+		lso_header_size -= hopbyhop;
 		/* Fill in the LSO prefix */
 		tx_desc->lso.mss_hdr_size = cpu_to_be32(
 			shinfo->gso_size << 16 | lso_header_size);
 
-		/* Copy headers;
-		 * note that we already verified that it is linear */
-		memcpy(tx_desc->lso.header, skb->data, lso_header_size);
 
+		if (unlikely(hopbyhop)) {
+			/* remove the HBH header.
+			 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
+			 */
+			memcpy(tx_desc->lso.header, skb->data, ETH_HLEN + sizeof(*h6));
+			h6 = (struct ipv6hdr *)((char *)tx_desc->lso.header + ETH_HLEN);
+			h6->nexthdr = IPPROTO_TCP;
+			/* Copy the TCP header after the IPv6 one */
+			memcpy(h6 + 1,
+			       skb->data + ETH_HLEN + sizeof(*h6) +
+					sizeof(struct hop_jumbo_hdr),
+			       tcp_hdrlen(skb));
+			/* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
+		} else {
+			/* Copy headers;
+			 * note that we already verified that it is linear
+			 */
+			memcpy(tx_desc->lso.header, skb->data, lso_header_size);
+		}
 		ring->tso_packets++;
 
 		i = shinfo->gso_segs;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index d27986869b8b..bf3bca79e160 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -4920,6 +4920,7 @@ static void mlx5e_build_nic_netdev(struct net_device *netdev)
 
 	netdev->priv_flags       |= IFF_UNICAST_FLT;
 
+	netif_set_tso_max_size(netdev, GSO_MAX_SIZE);
 	mlx5e_set_netdev_dev_addr(netdev);
 	mlx5e_ipsec_build_netdev(priv);
 	mlx5e_ktls_build_netdev(priv);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index fb11081001a0..24de37b79f5a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -2038,7 +2038,7 @@ mlx5e_hw_gro_skb_has_enough_space(struct sk_buff *skb, u16 data_bcnt)
 {
 	int nr_frags = skb_shinfo(skb)->nr_frags;
 
-	return PAGE_SIZE * nr_frags + data_bcnt <= GSO_MAX_SIZE;
+	return PAGE_SIZE * nr_frags + data_bcnt <= GRO_LEGACY_MAX_SIZE;
 }
 
 static void
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index 5855d8f9c509..50d14cec4894 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -40,6 +40,7 @@
 #include "en_accel/en_accel.h"
 #include "en_accel/ipsec_rxtx.h"
 #include "en/ptp.h"
+#include <net/ipv6.h>
 
 static void mlx5e_dma_unmap_wqe_err(struct mlx5e_txqsq *sq, u8 num_dma)
 {
@@ -91,6 +92,13 @@ static inline u16 mlx5e_calc_min_inline(enum mlx5_inline_modes mode,
 	return min_t(u16, hlen, skb_headlen(skb));
 }
 
+#define MLX5_UNSAFE_MEMCPY_DISCLAIMER				\
+	"This copy has been bounds-checked earlier in "		\
+	"mlx5i_sq_calc_wqe_attr() and intentionally "		\
+	"crosses a flex array boundary. Since it is "		\
+	"performance sensitive, splitting the copy is "		\
+	"undesirable."
+
 static inline void mlx5e_insert_vlan(void *start, struct sk_buff *skb, u16 ihs)
 {
 	struct vlan_ethhdr *vhdr = (struct vlan_ethhdr *)start;
@@ -100,7 +108,10 @@ static inline void mlx5e_insert_vlan(void *start, struct sk_buff *skb, u16 ihs)
 	memcpy(&vhdr->addrs, skb->data, cpy1_sz);
 	vhdr->h_vlan_proto = skb->vlan_proto;
 	vhdr->h_vlan_TCI = cpu_to_be16(skb_vlan_tag_get(skb));
-	memcpy(&vhdr->h_vlan_encapsulated_proto, skb->data + cpy1_sz, cpy2_sz);
+	unsafe_memcpy(&vhdr->h_vlan_encapsulated_proto,
+		      skb->data + cpy1_sz,
+		      cpy2_sz,
+		      MLX5_UNSAFE_MEMCPY_DISCLAIMER);
 }
 
 static inline void
@@ -130,23 +141,32 @@ mlx5e_txwqe_build_eseg_csum(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 		sq->stats->csum_none++;
 }
 
+/* Returns the number of header bytes that we plan
+ * to inline later in the transmit descriptor
+ */
 static inline u16
-mlx5e_tx_get_gso_ihs(struct mlx5e_txqsq *sq, struct sk_buff *skb)
+mlx5e_tx_get_gso_ihs(struct mlx5e_txqsq *sq, struct sk_buff *skb, int *hopbyhop)
 {
 	struct mlx5e_sq_stats *stats = sq->stats;
 	u16 ihs;
 
+	*hopbyhop = 0;
 	if (skb->encapsulation) {
 		ihs = skb_inner_transport_offset(skb) + inner_tcp_hdrlen(skb);
 		stats->tso_inner_packets++;
 		stats->tso_inner_bytes += skb->len - ihs;
 	} else {
-		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4)
+		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
 			ihs = skb_transport_offset(skb) + sizeof(struct udphdr);
-		else
+		} else {
 			ihs = skb_transport_offset(skb) + tcp_hdrlen(skb);
+			if (ipv6_has_hopopt_jumbo(skb)) {
+				*hopbyhop = sizeof(struct hop_jumbo_hdr);
+				ihs -= sizeof(struct hop_jumbo_hdr);
+			}
+		}
 		stats->tso_packets++;
-		stats->tso_bytes += skb->len - ihs;
+		stats->tso_bytes += skb->len - ihs - *hopbyhop;
 	}
 
 	return ihs;
@@ -208,6 +228,7 @@ struct mlx5e_tx_attr {
 	__be16 mss;
 	u16 insz;
 	u8 opcode;
+	u8 hopbyhop;
 };
 
 struct mlx5e_tx_wqe_attr {
@@ -244,14 +265,16 @@ static void mlx5e_sq_xmit_prepare(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	struct mlx5e_sq_stats *stats = sq->stats;
 
 	if (skb_is_gso(skb)) {
-		u16 ihs = mlx5e_tx_get_gso_ihs(sq, skb);
+		int hopbyhop;
+		u16 ihs = mlx5e_tx_get_gso_ihs(sq, skb, &hopbyhop);
 
 		*attr = (struct mlx5e_tx_attr) {
 			.opcode    = MLX5_OPCODE_LSO,
 			.mss       = cpu_to_be16(skb_shinfo(skb)->gso_size),
 			.ihs       = ihs,
 			.num_bytes = skb->len + (skb_shinfo(skb)->gso_segs - 1) * ihs,
-			.headlen   = skb_headlen(skb) - ihs,
+			.headlen   = skb_headlen(skb) - ihs - hopbyhop,
+			.hopbyhop  = hopbyhop,
 		};
 
 		stats->packets += skb_shinfo(skb)->gso_segs;
@@ -365,7 +388,8 @@ mlx5e_sq_xmit_wqe(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	struct mlx5_wqe_eth_seg  *eseg;
 	struct mlx5_wqe_data_seg *dseg;
 	struct mlx5e_tx_wqe_info *wi;
-
+	u16 ihs = attr->ihs;
+	struct ipv6hdr *h6;
 	struct mlx5e_sq_stats *stats = sq->stats;
 	int num_dma;
 
@@ -379,21 +403,40 @@ mlx5e_sq_xmit_wqe(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 
 	eseg->mss = attr->mss;
 
-	if (attr->ihs) {
-		if (skb_vlan_tag_present(skb)) {
-			eseg->inline_hdr.sz |= cpu_to_be16(attr->ihs + VLAN_HLEN);
-			mlx5e_insert_vlan(eseg->inline_hdr.start, skb, attr->ihs);
+	if (ihs) {
+		u8 *start = eseg->inline_hdr.start;
+
+		if (unlikely(attr->hopbyhop)) {
+			/* remove the HBH header.
+			 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
+			 */
+			if (skb_vlan_tag_present(skb)) {
+				mlx5e_insert_vlan(start, skb, ETH_HLEN + sizeof(*h6));
+				ihs += VLAN_HLEN;
+				h6 = (struct ipv6hdr *)(start + sizeof(struct vlan_ethhdr));
+			} else {
+				unsafe_memcpy(start, skb->data,
+					      ETH_HLEN + sizeof(*h6),
+					      MLX5_UNSAFE_MEMCPY_DISCLAIMER);
+				h6 = (struct ipv6hdr *)(start + ETH_HLEN);
+			}
+			h6->nexthdr = IPPROTO_TCP;
+			/* Copy the TCP header after the IPv6 one */
+			memcpy(h6 + 1,
+			       skb->data + ETH_HLEN + sizeof(*h6) +
+					sizeof(struct hop_jumbo_hdr),
+			       tcp_hdrlen(skb));
+			/* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
+		} else if (skb_vlan_tag_present(skb)) {
+			mlx5e_insert_vlan(start, skb, ihs);
+			ihs += VLAN_HLEN;
 			stats->added_vlan_packets++;
 		} else {
-			eseg->inline_hdr.sz |= cpu_to_be16(attr->ihs);
-			unsafe_memcpy(eseg->inline_hdr.start, skb->data, attr->ihs,
-				/* This copy has been bounds-checked earlier in
-				 * mlx5i_sq_calc_wqe_attr() and intentionally
-				 * crosses a flex array boundary. Since it is
-				 * performance sensitive, splitting the copy is
-				 * undesirable.
-				 */);
+			unsafe_memcpy(eseg->inline_hdr.start, skb->data,
+				      attr->ihs,
+				      MLX5_UNSAFE_MEMCPY_DISCLAIMER);
 		}
+		eseg->inline_hdr.sz |= cpu_to_be16(ihs);
 		dseg += wqe_attr->ds_cnt_inl;
 	} else if (skb_vlan_tag_present(skb)) {
 		eseg->insert.type = cpu_to_be16(MLX5_ETH_WQE_INSERT_VLAN);
@@ -404,7 +447,7 @@ mlx5e_sq_xmit_wqe(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	}
 
 	dseg += wqe_attr->ds_cnt_ids;
-	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr->ihs,
+	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr->ihs + attr->hopbyhop,
 					  attr->headlen, dseg);
 	if (unlikely(num_dma < 0))
 		goto err_drop;
@@ -924,12 +967,34 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	eseg->mss = attr.mss;
 
 	if (attr.ihs) {
-		memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
+		if (unlikely(attr.hopbyhop)) {
+			struct ipv6hdr *h6;
+
+			/* remove the HBH header.
+			 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
+			 */
+			unsafe_memcpy(eseg->inline_hdr.start, skb->data,
+				      ETH_HLEN + sizeof(*h6),
+				      MLX5_UNSAFE_MEMCPY_DISCLAIMER);
+			h6 = (struct ipv6hdr *)((char *)eseg->inline_hdr.start + ETH_HLEN);
+			h6->nexthdr = IPPROTO_TCP;
+			/* Copy the TCP header after the IPv6 one */
+			unsafe_memcpy(h6 + 1,
+				      skb->data + ETH_HLEN + sizeof(*h6) +
+						  sizeof(struct hop_jumbo_hdr),
+				      tcp_hdrlen(skb),
+				      MLX5_UNSAFE_MEMCPY_DISCLAIMER);
+			/* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
+		} else {
+			unsafe_memcpy(eseg->inline_hdr.start, skb->data,
+				      attr.ihs,
+				      MLX5_UNSAFE_MEMCPY_DISCLAIMER);
+		}
 		eseg->inline_hdr.sz = cpu_to_be16(attr.ihs);
 		dseg += wqe_attr.ds_cnt_inl;
 	}
 
-	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr.ihs,
+	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr.ihs + attr.hopbyhop,
 					  attr.headlen, dseg);
 	if (unlikely(num_dma < 0))
 		goto err_drop;
diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
index a69d756e09b9..b2536d2c218a 100644
--- a/drivers/net/ethernet/sfc/ef100_nic.c
+++ b/drivers/net/ethernet/sfc/ef100_nic.c
@@ -1008,7 +1008,8 @@ static int ef100_process_design_param(struct efx_nic *efx,
 		}
 		return 0;
 	case ESE_EF100_DP_GZ_TSO_MAX_PAYLOAD_LEN:
-		nic_data->tso_max_payload_len = min_t(u64, reader->value, GSO_MAX_SIZE);
+		nic_data->tso_max_payload_len = min_t(u64, reader->value,
+						      GSO_LEGACY_MAX_SIZE);
 		netif_set_tso_max_size(efx->net_dev,
 				       nic_data->tso_max_payload_len);
 		return 0;
diff --git a/drivers/net/ethernet/sfc/falcon/tx.c b/drivers/net/ethernet/sfc/falcon/tx.c
index f7306e93a8b8..b9369483758c 100644
--- a/drivers/net/ethernet/sfc/falcon/tx.c
+++ b/drivers/net/ethernet/sfc/falcon/tx.c
@@ -98,7 +98,8 @@ unsigned int ef4_tx_max_skb_descs(struct ef4_nic *efx)
 	/* Possibly more for PCIe page boundaries within input fragments */
 	if (PAGE_SIZE > EF4_PAGE_SIZE)
 		max_descs += max_t(unsigned int, MAX_SKB_FRAGS,
-				   DIV_ROUND_UP(GSO_MAX_SIZE, EF4_PAGE_SIZE));
+				   DIV_ROUND_UP(GSO_LEGACY_MAX_SIZE,
+						EF4_PAGE_SIZE));
 
 	return max_descs;
 }
diff --git a/drivers/net/ethernet/sfc/tx_common.c b/drivers/net/ethernet/sfc/tx_common.c
index 9bc8281b7f5b..658ea2d34070 100644
--- a/drivers/net/ethernet/sfc/tx_common.c
+++ b/drivers/net/ethernet/sfc/tx_common.c
@@ -416,7 +416,8 @@ unsigned int efx_tx_max_skb_descs(struct efx_nic *efx)
 	/* Possibly more for PCIe page boundaries within input fragments */
 	if (PAGE_SIZE > EFX_PAGE_SIZE)
 		max_descs += max_t(unsigned int, MAX_SKB_FRAGS,
-				   DIV_ROUND_UP(GSO_MAX_SIZE, EFX_PAGE_SIZE));
+				   DIV_ROUND_UP(GSO_LEGACY_MAX_SIZE,
+						EFX_PAGE_SIZE));
 
 	return max_descs;
 }
diff --git a/drivers/net/ethernet/synopsys/dwc-xlgmac.h b/drivers/net/ethernet/synopsys/dwc-xlgmac.h
index 98e3a271e017..a848e10f3ea4 100644
--- a/drivers/net/ethernet/synopsys/dwc-xlgmac.h
+++ b/drivers/net/ethernet/synopsys/dwc-xlgmac.h
@@ -38,7 +38,8 @@
 #define XLGMAC_RX_DESC_MAX_DIRTY	(XLGMAC_RX_DESC_CNT >> 3)
 
 /* Descriptors required for maximum contiguous TSO/GSO packet */
-#define XLGMAC_TX_MAX_SPLIT	((GSO_MAX_SIZE / XLGMAC_TX_MAX_BUF_SIZE) + 1)
+#define XLGMAC_TX_MAX_SPLIT	\
+	((GSO_LEGACY_MAX_SIZE / XLGMAC_TX_MAX_BUF_SIZE) + 1)
 
 /* Maximum possible descriptors needed for a SKB */
 #define XLGMAC_TX_MAX_DESC_NR	(MAX_SKB_FRAGS + XLGMAC_TX_MAX_SPLIT + 2)
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 866af2cc27a3..6da36cb8af80 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1349,7 +1349,7 @@ static int rndis_netdev_set_hwcaps(struct rndis_device *rndis_device,
 	struct net_device_context *net_device_ctx = netdev_priv(net);
 	struct ndis_offload hwcaps;
 	struct ndis_offload_params offloads;
-	unsigned int gso_max_size = GSO_MAX_SIZE;
+	unsigned int gso_max_size = GSO_LEGACY_MAX_SIZE;
 	int ret;
 
 	/* Find HW offload capabilities */
diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index 720394c0639b..14e8d04cb434 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -191,6 +191,8 @@ static void gen_lo_setup(struct net_device *dev,
 	dev->netdev_ops		= dev_ops;
 	dev->needs_free_netdev	= true;
 	dev->priv_destructor	= dev_destructor;
+
+	netif_set_tso_max_size(dev, GSO_MAX_SIZE);
 }
 
 /* The loopback device is special. There is only one instance
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index f474e79a7745..466da01ba2e3 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1647,6 +1647,7 @@ static void veth_setup(struct net_device *dev)
 	dev->hw_features = VETH_FEATURES;
 	dev->hw_enc_features = VETH_FEATURES;
 	dev->mpls_features = NETIF_F_HW_CSUM | NETIF_F_GSO_SOFTWARE;
+	netif_set_tso_max_size(dev, GSO_MAX_SIZE);
 }
 
 /*
diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 44ca6110213c..79b2827e4081 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -667,7 +667,7 @@ static void fcoe_netdev_features_change(struct fc_lport *lport,
 
 	if (netdev->features & NETIF_F_FSO) {
 		lport->seq_offload = 1;
-		lport->lso_max = netdev->gso_max_size;
+		lport->lso_max = min(netdev->gso_max_size, GSO_LEGACY_MAX_SIZE);
 		FCOE_NETDEV_DBG(netdev, "Supports LSO for max len 0x%x\n",
 				lport->lso_max);
 	} else {