Subject: Re: [patch net-next 1/7] rtnl: use dev_set_mac_address() instead of plain ndo_

From: Stephen Hemminger <[email-masked]>
Date: Tue, 1 Jan 2013 10:33:06 -0800

On Tue,  1 Jan 2013 14:30:13 +0100
Jiri Pirko <[email-masked]> wrote:

> Benefit from existence of dev_set_mac_address() and remove duplicate
> code.
> 
> Signed-off-by: Jiri Pirko <[email-masked]>
> ---
>  net/core/rtnetlink.c | 20 ++------------------
>  1 file changed, 2 insertions(+), 18 deletions(-)
> 
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index 2ef7a56..78d05a9 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -1310,7 +1310,6 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
>  		      struct nlattr **tb, char *ifname, int modified)
>  {
>  	const struct net_device_ops *ops = dev->netdev_ops;
> -	int send_addr_notify = 0;
>  	int err;
>  
>  	if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD]) {
> @@ -1363,16 +1362,6 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
>  		struct sockaddr *sa;
>  		int len;
>  
> -		if (!ops->ndo_set_mac_address) {
> -			err = -EOPNOTSUPP;
> -			goto errout;
> -		}
> -
> -		if (!netif_device_present(dev)) {
> -			err = -ENODEV;
> -			goto errout;
> -		}
> -
>  		len = sizeof(sa_family_t) + dev->addr_len;
>  		sa = kmalloc(len, GFP_KERNEL);
>  		if (!sa) {
> @@ -1382,13 +1371,11 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
>  		sa->sa_family = dev->type;
>  		memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
>  		       dev->addr_len);
> -		err = ops->ndo_set_mac_address(dev, sa);
> +		err = dev_set_mac_address(dev, sa);
>  		kfree(sa);
>  		if (err)
>  			goto errout;
> -		send_addr_notify = 1;
>  		modified = 1;
> -		add_device_randomness(dev->dev_addr, dev->addr_len);
>  	}
>  
>  	if (tb[IFLA_MTU]) {
> @@ -1425,7 +1412,7 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
>  
>  	if (tb[IFLA_BROADCAST]) {
>  		nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
> -		send_addr_notify = 1;
> +		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
>  	}
>  
>  	if (ifm->ifi_flags || ifm->ifi_change) {
> @@ -1546,9 +1533,6 @@ errout:
>  		net_warn_ratelimited("A link change request failed with some changes committed already. Interface %s may have been left with an inconsistent configuration, please check.\n",
>  				     dev->name);
>  
> -	if (send_addr_notify)
> -		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
> -
>  	return err;
>  }
>  

This will cause call_netdevice_notifiers to be called twice if both IFLA_BROADCAST and IFLA_ADDRESS
are changed in one request. Not sure if that would break anything?