From f51048c3e07b68c90b21a77541fc4b208f9244d7 Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Thu, 6 Jul 2017 15:01:57 -0700 Subject: bonding: avoid NETDEV_CHANGEMTU event when unregistering slave As Hongjun/Nicolas summarized in their original patch: " When a device changes from one netns to another, it's first unregistered, then the netns reference is updated and the dev is registered in the new netns. Thus, when a slave moves to another netns, it is first unregistered. This triggers a NETDEV_UNREGISTER event which is caught by the bonding driver. The driver calls bond_release(), which calls dev_set_mtu() and thus triggers NETDEV_CHANGEMTU (the device is still in the old netns). " This is a very special case, because the device is being unregistered no one should still care about the NETDEV_CHANGEMTU event triggered at this point, we can avoid broadcasting this event on this path, and avoid touching inetdev_event()/addrconf_notify() path. It requires to export __dev_set_mtu() to bonding driver. Reported-by: Hongjun Li Reported-by: Nicolas Dichtel Cc: Jay Vosburgh Cc: Veaceslav Falico Cc: Andy Gospodarek Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- include/linux/netdevice.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e48ee2eaaa3e..779b23595596 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3284,6 +3284,7 @@ void __dev_notify_flags(struct net_device *, unsigned int old_flags, int dev_change_name(struct net_device *, const char *); int dev_set_alias(struct net_device *, const char *, size_t); int dev_change_net_namespace(struct net_device *, struct net *, const char *); +int __dev_set_mtu(struct net_device *, int); int dev_set_mtu(struct net_device *, int); void dev_set_group(struct net_device *, int); int dev_set_mac_address(struct net_device *, struct sockaddr *); -- cgit v1.2.2