Patch "vxlan: vxlan dev should inherit lowerdev's gso_max_size" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

vxlan: vxlan dev should inherit lowerdev's gso_max_size

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
vxlan-vxlan-dev-should-inherit-lowerdev-s-gso_max_size.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Felix Manlunas <[email protected]>
Date: Wed, 29 Mar 2017 17:56:43 -0700
Subject: vxlan: vxlan dev should inherit lowerdev's gso_max_size

From: Felix Manlunas <[email protected]>

[ Upstream commit d6acfeb17d030bb3907e77c048b0e7783ad8e5a9 ]

vxlan dev currently ignores lowerdev's gso_max_size, which adversely affects TSO performance of liquidio if it's the lowerdev. Egress TCP packets' skb->len often exceed liquidio's advertised gso_max_size. This may happen on other NIC drivers.

Fix it by assigning lowerdev's gso_max_size to that of vxlan dev. Might as well do likewise for gso_max_segs.

Single flow TSO throughput of liquidio as lowerdev (using iperf3):

Before the patch: 139 Mbps
After the patch : 8.68 Gbps
Percent increase: 6,144 %

---
 drivers/net/vxlan.c |    5 +++++
 1 file changed, 5 insertions(+)

@@ -2834,6 +2834,11 @@ static int vxlan_dev_configure(struct ne
 		needed_headroom = lowerdev->hard_header_len;
 	}
 
+	if (lowerdev) {
+		dev->gso_max_size = lowerdev->gso_max_size;
+		dev->gso_max_segs = lowerdev->gso_max_segs;
+	}
+
 	if (conf->mtu) {
 		err = __vxlan_change_mtu(dev, lowerdev, dst, conf->mtu, false);
 		if (err)

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/vxlan-vxlan-dev-should-inherit-lowerdev-s-gso_max_size.patch