[PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[David Ahern]

This series fixes mtu and fragmentation for tunnels using lwtunnel
output redirect, and fixes GSO for MPLS for locally originated traffic
reported by Lennert Buytenhek.

A follow on series will address fragmentation and GSO for forwarded
MPLS traffic. Hardware offload of GSO with MPLS also needs to be
addressed.

Simon: Can you verify this works with OVS for single and multiple
       labels?

v4
- more updates to mpls_gso_segment per Alex's comments (thanks, Alex)
- updates to teaching OVS about marking MPLS labels as the network header
 
v3
- updates to mpls_gso_segment per Alex's comments
- dropped skb->encapsulation = 1 from mpls_xmit per Alex's comment

v2
- consistent use of network_header in skb to fix GSO for MPLS
- update MPLS code in OVS to network_header and inner_network_header


David Ahern (2):
  net: mpls: Fixups for GSO
  net: veth: Set features for MPLS

Roopa Prabhu (1):
  net: lwtunnel: Handle fragmentation

 drivers/net/veth.c        |  1 +
 include/net/lwtunnel.h    | 44 ++++++++++++++++++++++++++++++++++++++++++++
 net/core/lwtunnel.c       | 35 +++++++++++++++++++++++++++++++++++
 net/ipv4/ip_output.c      |  8 ++++++++
 net/ipv4/route.c          |  4 +++-
 net/ipv6/ip6_output.c     |  8 ++++++++
 net/ipv6/route.c          |  4 +++-
 net/mpls/mpls_gso.c       | 40 +++++++++++++++++++++++++++++-----------
 net/mpls/mpls_iptunnel.c  | 13 +++++++++----
 net/openvswitch/actions.c |  9 +++++++--
 10 files changed, 147 insertions(+), 19 deletions(-)

-- 
2.1.4

[PATCH net-next v4 1/3] net: lwtunnel: Handle fragmentation

[David Ahern]

From: Roopa Prabhu <roopa@cumulusnetworks.com>

Today mpls iptunnel lwtunnel_output redirect expects the tunnel
output function to handle fragmentation. This is ok but can be
avoided if we did not do the mpls output redirect too early.
ie we could wait until ip fragmentation is done and then call
mpls output for each ip fragment.

To make this work we will need,
1) the lwtunnel state to carry encap headroom
2) and do the redirect to the encap output handler on the ip fragment
(essentially do the output redirect after fragmentation)

This patch adds tunnel headroom in lwtstate to make sure we
account for tunnel data in mtu calculations during fragmentation
and adds new xmit redirect handler to redirect to lwtunnel xmit func
after ip fragmentation.

This includes IPV6 and some mtu fixes and testing from David Ahern.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
---
 include/net/lwtunnel.h   | 44 ++++++++++++++++++++++++++++++++++++++++++++
 net/core/lwtunnel.c      | 35 +++++++++++++++++++++++++++++++++++
 net/ipv4/ip_output.c     |  8 ++++++++
 net/ipv4/route.c         |  4 +++-
 net/ipv6/ip6_output.c    |  8 ++++++++
 net/ipv6/route.c         |  4 +++-
 net/mpls/mpls_iptunnel.c |  9 +++++----
 7 files changed, 106 insertions(+), 6 deletions(-)

diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h
index e9f116e29c22..ea3f80f58fd6 100644
--- a/include/net/lwtunnel.h
+++ b/include/net/lwtunnel.h
@@ -13,6 +13,13 @@
 /* lw tunnel state flags */
 #define LWTUNNEL_STATE_OUTPUT_REDIRECT	BIT(0)
 #define LWTUNNEL_STATE_INPUT_REDIRECT	BIT(1)
+#define LWTUNNEL_STATE_XMIT_REDIRECT	BIT(2)
+
+enum {
+	LWTUNNEL_XMIT_DONE,
+	LWTUNNEL_XMIT_CONTINUE,
+};
+
 
 struct lwtunnel_state {
 	__u16		type;
@@ -21,6 +28,7 @@ struct lwtunnel_state {
 	int		(*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
 	int		(*orig_input)(struct sk_buff *);
 	int             len;
+	__u16		headroom;
 	__u8            data[0];
 };
 
@@ -34,6 +42,7 @@ struct lwtunnel_encap_ops {
 			  struct lwtunnel_state *lwtstate);
 	int (*get_encap_size)(struct lwtunnel_state *lwtstate);
 	int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b);
+	int (*xmit)(struct sk_buff *skb);
 };
 
 #ifdef CONFIG_LWTUNNEL
@@ -75,6 +84,24 @@ static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
 
 	return false;
 }
+
+static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
+{
+	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_XMIT_REDIRECT))
+		return true;
+
+	return false;
+}
+
+static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
+					     unsigned int mtu)
+{
+	if (lwtunnel_xmit_redirect(lwtstate) && lwtstate->headroom < mtu)
+		return lwtstate->headroom;
+
+	return 0;
+}
+
 int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
 			   unsigned int num);
 int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
@@ -90,6 +117,7 @@ struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
 int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
 int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
 int lwtunnel_input(struct sk_buff *skb);
+int lwtunnel_xmit(struct sk_buff *skb);
 
 #else
 
@@ -117,6 +145,17 @@ static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
 	return false;
 }
 
+static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
+{
+	return false;
+}
+
+static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
+					     unsigned int mtu)
+{
+	return 0;
+}
+
 static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
 					 unsigned int num)
 {
@@ -170,6 +209,11 @@ static inline int lwtunnel_input(struct sk_buff *skb)
 	return -EOPNOTSUPP;
 }
 
+static inline int lwtunnel_xmit(struct sk_buff *skb)
+{
+	return -EOPNOTSUPP;
+}
+
 #endif /* CONFIG_LWTUNNEL */
 
 #define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))
diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c
index 669ecc9f884e..e5f84c26ba1a 100644
--- a/net/core/lwtunnel.c
+++ b/net/core/lwtunnel.c
@@ -251,6 +251,41 @@ int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(lwtunnel_output);
 
+int lwtunnel_xmit(struct sk_buff *skb)
+{
+	struct dst_entry *dst = skb_dst(skb);
+	const struct lwtunnel_encap_ops *ops;
+	struct lwtunnel_state *lwtstate;
+	int ret = -EINVAL;
+
+	if (!dst)
+		goto drop;
+
+	lwtstate = dst->lwtstate;
+
+	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
+	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
+		return 0;
+
+	ret = -EOPNOTSUPP;
+	rcu_read_lock();
+	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
+	if (likely(ops && ops->xmit))
+		ret = ops->xmit(skb);
+	rcu_read_unlock();
+
+	if (ret == -EOPNOTSUPP)
+		goto drop;
+
+	return ret;
+
+drop:
+	kfree_skb(skb);
+
+	return ret;
+}
+EXPORT_SYMBOL(lwtunnel_xmit);
+
 int lwtunnel_input(struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index dde37fb340bf..65569274efb8 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -73,6 +73,7 @@
 #include <net/icmp.h>
 #include <net/checksum.h>
 #include <net/inetpeer.h>
+#include <net/lwtunnel.h>
 #include <linux/igmp.h>
 #include <linux/netfilter_ipv4.h>
 #include <linux/netfilter_bridge.h>
@@ -197,6 +198,13 @@ static int ip_finish_output2(struct net *net, struct sock *sk, struct sk_buff *s
 		skb = skb2;
 	}
 
+	if (lwtunnel_xmit_redirect(dst->lwtstate)) {
+		int res = lwtunnel_xmit(skb);
+
+		if (res < 0 || res == LWTUNNEL_XMIT_DONE)
+			return res;
+	}
+
 	rcu_read_lock_bh();
 	nexthop = (__force u32) rt_nexthop(rt, ip_hdr(skb)->daddr);
 	neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index a1f2830d8110..3e992783c1d0 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1246,7 +1246,9 @@ static unsigned int ipv4_mtu(const struct dst_entry *dst)
 			mtu = 576;
 	}
 
-	return min_t(unsigned int, mtu, IP_MAX_MTU);
+	mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
+
+	return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
 }
 
 static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 1dfc402d9ad1..993fd9666f1b 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -56,6 +56,7 @@
 #include <net/checksum.h>
 #include <linux/mroute6.h>
 #include <net/l3mdev.h>
+#include <net/lwtunnel.h>
 
 static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
@@ -104,6 +105,13 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *
 		}
 	}
 
+	if (lwtunnel_xmit_redirect(dst->lwtstate)) {
+		int res = lwtunnel_xmit(skb);
+
+		if (res < 0 || res == LWTUNNEL_XMIT_DONE)
+			return res;
+	}
+
 	rcu_read_lock_bh();
 	nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
 	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 49817555449e..09d43ff11a8d 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1604,7 +1604,9 @@ static unsigned int ip6_mtu(const struct dst_entry *dst)
 	rcu_read_unlock();
 
 out:
-	return min_t(unsigned int, mtu, IP6_MAX_MTU);
+	mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
+
+	return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
 }
 
 static struct dst_entry *icmp6_dst_gc_list;
diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c
index 644a8da6d4bd..aed872cc05a6 100644
--- a/net/mpls/mpls_iptunnel.c
+++ b/net/mpls/mpls_iptunnel.c
@@ -37,7 +37,7 @@ static unsigned int mpls_encap_size(struct mpls_iptunnel_encap *en)
 	return en->labels * sizeof(struct mpls_shim_hdr);
 }
 
-static int mpls_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+static int mpls_xmit(struct sk_buff *skb)
 {
 	struct mpls_iptunnel_encap *tun_encap_info;
 	struct mpls_shim_hdr *hdr;
@@ -115,7 +115,7 @@ static int mpls_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 		net_dbg_ratelimited("%s: packet transmission failed: %d\n",
 				    __func__, err);
 
-	return 0;
+	return LWTUNNEL_XMIT_DONE;
 
 drop:
 	kfree_skb(skb);
@@ -153,7 +153,8 @@ static int mpls_build_state(struct net_device *dev, struct nlattr *nla,
 	if (ret)
 		goto errout;
 	newts->type = LWTUNNEL_ENCAP_MPLS;
-	newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT;
+	newts->flags |= LWTUNNEL_STATE_XMIT_REDIRECT;
+	newts->headroom = mpls_encap_size(tun_encap_info);
 
 	*ts = newts;
 
@@ -209,7 +210,7 @@ static int mpls_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
 
 static const struct lwtunnel_encap_ops mpls_iptun_ops = {
 	.build_state = mpls_build_state,
-	.output = mpls_output,
+	.xmit = mpls_xmit,
 	.fill_encap = mpls_fill_encap_info,
 	.get_encap_size = mpls_encap_nlsize,
 	.cmp_encap = mpls_encap_cmp,
-- 
2.1.4

[PATCH net-next v4 2/3] net: mpls: Fixups for GSO

[David Ahern]

As reported by Lennert the MPLS GSO code is failing to properly segment
large packets. There are a couple of problems:

1. the inner protocol is not set so the gso segment functions for inner
   protocol layers are not getting run, and

2  MPLS labels for packets that use the "native" (non-OVS) MPLS code
   are not properly accounted for in mpls_gso_segment.

The MPLS GSO code was added for OVS. It is re-using skb_mac_gso_segment
to call the gso segment functions for the higher layer protocols. That
means skb_mac_gso_segment is called twice -- once with the network
protocol set to MPLS and again with the network protocol set to the
inner protocol.

This patch sets the inner skb protocol addressing item 1 above and sets
the network_header and inner_network_header to mark where the MPLS labels
start and end. The MPLS code in OVS is also updated to set the two
network markers.

>From there the MPLS GSO code uses the difference between the network
header and the inner network header to know the size of the MPLS header
that was pushed. It then pulls the MPLS header, resets the mac_len and
protocol for the inner protocol and then calls skb_mac_gso_segment
to segment the skb.

Afterward the inner protocol segmentation is done the skb protocol
is set to mpls for each segment and the network and mac headers
restored.

Reported-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
---
 net/mpls/mpls_gso.c       | 40 +++++++++++++++++++++++++++++-----------
 net/mpls/mpls_iptunnel.c  |  4 ++++
 net/openvswitch/actions.c |  9 +++++++--
 3 files changed, 40 insertions(+), 13 deletions(-)

diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c
index 2055e57ed1c3..b4da6d8e8632 100644
--- a/net/mpls/mpls_gso.c
+++ b/net/mpls/mpls_gso.c
@@ -23,32 +23,50 @@ static struct sk_buff *mpls_gso_segment(struct sk_buff *skb,
 				       netdev_features_t features)
 {
 	struct sk_buff *segs = ERR_PTR(-EINVAL);
+	u16 mac_offset = skb->mac_header;
 	netdev_features_t mpls_features;
+	u16 mac_len = skb->mac_len;
 	__be16 mpls_protocol;
+	unsigned int mpls_hlen;
+
+	skb_reset_network_header(skb);
+	mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb);
+	if (unlikely(!pskb_may_pull(skb, mpls_hlen)))
+		goto out;
 
 	/* Setup inner SKB. */
 	mpls_protocol = skb->protocol;
 	skb->protocol = skb->inner_protocol;
 
-	/* Push back the mac header that skb_mac_gso_segment() has pulled.
-	 * It will be re-pulled by the call to skb_mac_gso_segment() below
-	 */
-	__skb_push(skb, skb->mac_len);
+	__skb_pull(skb, mpls_hlen);
+
+	skb->mac_len = 0;
+	skb_reset_mac_header(skb);
 
 	/* Segment inner packet. */
 	mpls_features = skb->dev->mpls_features & features;
 	segs = skb_mac_gso_segment(skb, mpls_features);
+	if (IS_ERR_OR_NULL(segs)) {
+		skb_gso_error_unwind(skb, mpls_protocol, mpls_hlen, mac_offset,
+				     mac_len);
+		goto out;
+	}
+	skb = segs;
+
+	mpls_hlen += mac_len;
+	do {
+		skb->mac_len = mac_len;
+		skb->protocol = mpls_protocol;
 
+		skb_reset_inner_network_header(skb);
 
-	/* Restore outer protocol. */
-	skb->protocol = mpls_protocol;
+		__skb_push(skb, mpls_hlen);
 
-	/* Re-pull the mac header that the call to skb_mac_gso_segment()
-	 * above pulled.  It will be re-pushed after returning
-	 * skb_mac_gso_segment(), an indirect caller of this function.
-	 */
-	__skb_pull(skb, skb->data - skb_mac_header(skb));
+		skb_reset_mac_header(skb);
+		skb_set_network_header(skb, mac_len);
+	} while ((skb = skb->next));
 
+out:
 	return segs;
 }
 
diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c
index aed872cc05a6..cf52cf30ac4b 100644
--- a/net/mpls/mpls_iptunnel.c
+++ b/net/mpls/mpls_iptunnel.c
@@ -90,7 +90,11 @@ static int mpls_xmit(struct sk_buff *skb)
 	if (skb_cow(skb, hh_len + new_header_size))
 		goto drop;
 
+	skb_set_inner_protocol(skb, skb->protocol);
+	skb_reset_inner_network_header(skb);
+
 	skb_push(skb, new_header_size);
+
 	skb_reset_network_header(skb);
 
 	skb->dev = out_dev;
diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c
index 1ecbd7715f6d..ca91fc33f8a9 100644
--- a/net/openvswitch/actions.c
+++ b/net/openvswitch/actions.c
@@ -162,10 +162,16 @@ static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 	if (skb_cow_head(skb, MPLS_HLEN) < 0)
 		return -ENOMEM;
 
+	if (!skb->inner_protocol) {
+		skb_set_inner_network_header(skb, skb->mac_len);
+		skb_set_inner_protocol(skb, skb->protocol);
+	}
+
 	skb_push(skb, MPLS_HLEN);
 	memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
 		skb->mac_len);
 	skb_reset_mac_header(skb);
+	skb_set_network_header(skb, skb->mac_len);
 
 	new_mpls_lse = (__be32 *)skb_mpls_header(skb);
 	*new_mpls_lse = mpls->mpls_lse;
@@ -173,8 +179,6 @@ static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 	skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
 
 	update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
-	if (!skb->inner_protocol)
-		skb_set_inner_protocol(skb, skb->protocol);
 	skb->protocol = mpls->mpls_ethertype;
 
 	invalidate_flow_key(key);
@@ -198,6 +202,7 @@ static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 
 	__skb_pull(skb, MPLS_HLEN);
 	skb_reset_mac_header(skb);
+	skb_set_network_header(skb, skb->mac_len);
 
 	/* skb_mpls_header() is used to locate the ethertype
 	 * field correctly in the presence of VLAN tags.
-- 
2.1.4

[PATCH net-next v4 3/3] net: veth: Set features for MPLS

[David Ahern]

veth does not really transmit packets only moves the skb from one
netdev to another so gso and checksum is not really needed. Add
the features to mpls_features to get the same benefit and performance
with MPLS as without it.

Reported-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
---
 drivers/net/veth.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index f37a6e61d4ad..5db320a4d5cf 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -340,6 +340,7 @@ 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;
 }
 
 /*
-- 
2.1.4

Re: [PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[David Miller]

From: David Ahern <dsa@cumulusnetworks.com>
Date: Wed, 24 Aug 2016 20:10:42 -0700

> This series fixes mtu and fragmentation for tunnels using lwtunnel
> output redirect, and fixes GSO for MPLS for locally originated traffic
> reported by Lennert Buytenhek.
> 
> A follow on series will address fragmentation and GSO for forwarded
> MPLS traffic. Hardware offload of GSO with MPLS also needs to be
> addressed.
> 
> Simon: Can you verify this works with OVS for single and multiple
>        labels?

Simon, I'm waiting on your testing before I apply this series.

Thanks.

Re: [PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[Simon Horman]

On Fri, Aug 26, 2016 at 11:41:37AM -0700, David Miller wrote:
> From: David Ahern <dsa@cumulusnetworks.com>
> Date: Wed, 24 Aug 2016 20:10:42 -0700
> 
> > This series fixes mtu and fragmentation for tunnels using lwtunnel
> > output redirect, and fixes GSO for MPLS for locally originated traffic
> > reported by Lennert Buytenhek.
> > 
> > A follow on series will address fragmentation and GSO for forwarded
> > MPLS traffic. Hardware offload of GSO with MPLS also needs to be
> > addressed.
> > 
> > Simon: Can you verify this works with OVS for single and multiple
> >        labels?
> 
> Simon, I'm waiting on your testing before I apply this series.

Sorry for the delay. I will test it ASAP.

Re: [PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[Simon Horman]

On Mon, Aug 29, 2016 at 02:07:30PM +0200, Simon Horman wrote:
> On Fri, Aug 26, 2016 at 11:41:37AM -0700, David Miller wrote:
> > From: David Ahern <dsa@cumulusnetworks.com>
> > Date: Wed, 24 Aug 2016 20:10:42 -0700
> > 
> > > This series fixes mtu and fragmentation for tunnels using lwtunnel
> > > output redirect, and fixes GSO for MPLS for locally originated traffic
> > > reported by Lennert Buytenhek.
> > > 
> > > A follow on series will address fragmentation and GSO for forwarded
> > > MPLS traffic. Hardware offload of GSO with MPLS also needs to be
> > > addressed.
> > > 
> > > Simon: Can you verify this works with OVS for single and multiple
> > >        labels?
> > 
> > Simon, I'm waiting on your testing before I apply this series.
> 
> Sorry for the delay. I will test it ASAP.

Sorry once again for the delay,

I have tested this series for both of the following:
* IPv4 in MPLS (just after the ethernet header)
* IPv4 in MPLS in GRE (TEB)

Things seem to work fine.

Tested-by: Simon Horman <simon.horman@netronome.com>

Expanding a little on the above:

* I tested this using the test cases I have been working on for OvS here:
  http://www.spinics.net/lists/netdev/msg391755.html

  Those test make use of namespaces connected using veth and
  push/pop_mpls actions.

* As the above is quite new I also tested the patchset using my somewhat
  more clumsy local test environment which uses KVM, virtio net and
  push/pop_mpls actions.

Re: [PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[David Ahern]

On 8/29/16 6:29 AM, Simon Horman wrote: 
> I have tested this series for both of the following:
> * IPv4 in MPLS (just after the ethernet header)
> * IPv4 in MPLS in GRE (TEB)
> 
> Things seem to work fine.
> 
> Tested-by: Simon Horman <simon.horman@netronome.com>
> 
> Expanding a little on the above:
> 
> * I tested this using the test cases I have been working on for OvS here:
>   http://www.spinics.net/lists/netdev/msg391755.html
> 
>   Those test make use of namespaces connected using veth and
>   push/pop_mpls actions.

The 3rd patch in this set enables GSO for MPLS in veth meaning no software segmentation is done by default.

> 
> * As the above is quite new I also tested the patchset using my somewhat
>   more clumsy local test environment which uses KVM, virtio net and
>   push/pop_mpls actions.
> 

Awesome. Thanks for confirming.

Re: [PATCH net-next v4 0/3] net: mpls: fragmentation and gso fixes for locally originated traffic

[David Miller]

From: David Ahern <dsa@cumulusnetworks.com>
Date: Wed, 24 Aug 2016 20:10:42 -0700

> This series fixes mtu and fragmentation for tunnels using lwtunnel
> output redirect, and fixes GSO for MPLS for locally originated traffic
> reported by Lennert Buytenhek.
> 
> A follow on series will address fragmentation and GSO for forwarded
> MPLS traffic. Hardware offload of GSO with MPLS also needs to be
> addressed.
> 
> Simon: Can you verify this works with OVS for single and multiple
>        labels?

Series applied, thanks.