[3.8.y.z extended stable] Patch "macvtap: Do not double-count received packets" has been added to staging queue

[Kamal Mostafa]

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

    macvtap: Do not double-count received packets

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.16.

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

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From a49a300eb69523a0ab1925a0f167a24ce9cf3259 Mon Sep 17 00:00:00 2001
From: Vlad Yasevich <vyasevic at redhat.com>
Date: Tue, 26 Nov 2013 12:37:12 -0500
Subject: macvtap: Do not double-count received packets

[ Upstream commit 006da7b07bc4d3a7ffabad17cf639eec6849c9dc ]

Currently macvlan will count received packets after calling each
vlans receive handler.   Macvtap attempts to count the packet
yet again when the user reads the packet from the tap socket.
This code doesn't do this consistently either.  Remove the
counting from macvtap and let only macvlan count received
packets.

Signed-off-by: Vlad Yasevich <vyasevic at redhat.com>
Acked-by: Michael S. Tsirkin <mst at redhat.com>
Acked-by: Jason Wang <jasowang at redhat.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/macvtap.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 15820ab..a4df37f 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -805,7 +805,6 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q,
 				const struct sk_buff *skb,
 				const struct iovec *iv, int len)
 {
-	struct macvlan_dev *vlan;
 	int ret;
 	int vnet_hdr_len = 0;
 	int vlan_offset = 0;
@@ -859,12 +858,6 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q,
 	copied += len;

 done:
-	rcu_read_lock_bh();
-	vlan = rcu_dereference_bh(q->vlan);
-	if (vlan)
-		macvlan_count_rx(vlan, copied - vnet_hdr_len, ret == 0, 0);
-	rcu_read_unlock_bh();
-
 	return ret ? ret : copied;
 }

--
1.8.3.2