[3.16.y-ckt stable] Patch "macvtap: unbreak receiving of gro skb with frag list" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    macvtap: unbreak receiving of gro skb with frag list

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt21.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 687ed1750b9e959f2f55ab86181bde38c2d4e9ad Mon Sep 17 00:00:00 2001
From: Jason Wang <jasowang at redhat.com>
Date: Fri, 23 Oct 2015 00:57:05 -0400
Subject: macvtap: unbreak receiving of gro skb with frag list

commit f23d538bc24a83c16127c2eb82c9cf1adc2b5149 upstream.

We don't have fraglist support in TAP_FEATURES. This will lead
software segmentation of gro skb with frag list. Fixes by having
frag list support in TAP_FEATURES.

With this patch single session of netperf receiving were restored from
about 5Gb/s to about 12Gb/s on mlx4.

Fixes a567dd6252 ("macvtap: simplify usage of tap_features")
Cc: Vlad Yasevich <vyasevic at redhat.com>
Cc: Michael S. Tsirkin <mst at redhat.com>
Signed-off-by: Jason Wang <jasowang at redhat.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/net/macvtap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index e8c21f911b6f..6185874a088e 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -68,7 +68,7 @@ static const struct proto_ops macvtap_socket_ops;
 #define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
 		      NETIF_F_TSO6 | NETIF_F_UFO)
 #define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
-#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG)
+#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG | NETIF_F_FRAGLIST)

 static struct macvlan_dev *macvtap_get_vlan_rcu(const struct net_device *dev)
 {