[PATCH 3.18 21/69] net: Resend IGMP memberships upon peer notification.

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Vlad Yasevich <vyasevich@xxxxxxxxx>


[ Upstream commit 37c343b4f4e70e9dc328ab04903c0ec8d154c1a4 ]

When we notify peers of potential changes,  it's also good to update
IGMP memberships.  For example, during VM migration, updating IGMP
memberships will redirect existing multicast streams to the VM at the
new location.

Signed-off-by: Vladislav Yasevich <vyasevic@xxxxxxxxxx>
Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/core/dev.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1248,6 +1248,7 @@ void netdev_notify_peers(struct net_devi
 {
 	rtnl_lock();
 	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
+	call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev);
 	rtnl_unlock();
 }
 EXPORT_SYMBOL(netdev_notify_peers);