From e8e1a4097434114b07c57d183daf617fc2998675 Mon Sep 17 00:00:00 2001
From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Date: Sun, 4 Feb 2018 06:45:38 -0800
Subject: [PATCH] netdev-linux: Report netdev change events when mac changed.

When mac addr of ports on bridge has been changed, for example,

$ ip link set dev eth0 address 00:11:22:33:44:55

we should reconfigure the datapath id and mac addr of local port.
But now openvswitch dont do that as expected.

A simple example of how to reproduce it:

$ ovs-vsctl add-br br0
$ ifconfig br0 			# for example, mac is c6:c6:d7:46:b4:4b
$ ip link set dev br0 address 00:11:22:33:44:55
$ ifconfig br0 			# mac of br0 will be 00:11:22:33:44:55

then repeat:
$ ip link set dev br0 address 00:11:22:33:44:55
$ ifconfig br0 			# mac of br0 will be c6:c6:d7:46:b4:4b

This patch reports the mac changed event when ports changed, then
openvswitch will reconfigure the datapath id and mac addr of local
port.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
---
 lib/netdev-linux.c     | 3 +++
 lib/netlink-notifier.c | 4 +---
 lib/netlink-notifier.h | 1 +
 lib/rtnetlink.c        | 9 +++++++++
 lib/rtnetlink.h        | 1 +
 5 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 6dae7964a89..4e0473cf331 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -747,6 +747,9 @@ netdev_linux_update(struct netdev_linux *dev,
                 dev->etheraddr = change->mac;
                 dev->cache_valid |= VALID_ETHERADDR;
                 dev->ether_addr_error = 0;
+
+                /* The mac addr has been changed, report it now. */
+                rtnetlink_report_link();
             }
 
             dev->ifindex = change->if_index;
diff --git a/lib/netlink-notifier.c b/lib/netlink-notifier.c
index 3acded418bd..7d8cfffa2af 100644
--- a/lib/netlink-notifier.c
+++ b/lib/netlink-notifier.c
@@ -32,8 +32,6 @@ VLOG_DEFINE_THIS_MODULE(netlink_notifier);
 
 COVERAGE_DEFINE(nln_changed);
 
-static void nln_report(const struct nln *nln, void *change, int group);
-
 struct nln {
     struct nl_sock *notify_sock; /* Netlink socket. */
     struct ovs_list all_notifiers;   /* All nln notifiers. */
@@ -225,7 +223,7 @@ nln_wait(struct nln *nln)
     }
 }
 
-static void
+void
 nln_report(const struct nln *nln, void *change, int group)
 {
     struct nln_notifier *notifier;
diff --git a/lib/netlink-notifier.h b/lib/netlink-notifier.h
index f6a5150390e..dd0c183de45 100644
--- a/lib/netlink-notifier.h
+++ b/lib/netlink-notifier.h
@@ -48,4 +48,5 @@ struct nln_notifier *nln_notifier_create(struct nln *, int multicast_group,
 void nln_notifier_destroy(struct nln_notifier *);
 void nln_run(struct nln *);
 void nln_wait(struct nln *);
+void nln_report(const struct nln *nln, void *change, int group);
 #endif /* netlink-notifier.h */
diff --git a/lib/rtnetlink.c b/lib/rtnetlink.c
index 5009cd504d7..4d9003b5270 100644
--- a/lib/rtnetlink.c
+++ b/lib/rtnetlink.c
@@ -180,3 +180,12 @@ rtnetlink_wait(void)
         nln_wait(nln);
     }
 }
+
+/* Report RTNLGRP_LINK netdev change events. */
+void
+rtnetlink_report_link(void)
+{
+    if (nln) {
+        nln_report(nln, NULL, RTNLGRP_LINK);
+    }
+}
diff --git a/lib/rtnetlink.h b/lib/rtnetlink.h
index 91ed4860f0a..518320f735f 100644
--- a/lib/rtnetlink.h
+++ b/lib/rtnetlink.h
@@ -67,4 +67,5 @@ rtnetlink_notifier_create(rtnetlink_notify_func *, void *aux);
 void rtnetlink_notifier_destroy(struct nln_notifier *);
 void rtnetlink_run(void);
 void rtnetlink_wait(void);
+void rtnetlink_report_link(void);
 #endif /* rtnetlink.h */