Lockdep complains about circular lock in 1 -> 2 -> 3 (see below).

Change the lock ordering to be:
- rtnl_lock
- dev_addr_sem
- netdev_ops (only for lower devices!)
- team_lock (or other per-upper device lock)

1. rtnl_lock -> netdev_ops -> dev_addr_sem

rtnl_setlink
  rtnl_lock
    do_setlink IFLA_ADDRESS on lower
      netdev_ops
        dev_addr_sem

2. rtnl_lock -> team_lock -> netdev_ops

rtnl_newlink
  rtnl_lock
    do_setlink IFLA_MASTER on lower
      do_set_master
        team_add_slave
          team_lock
            team_port_add
	      dev_set_mtu
	        netdev_ops

3. rtnl_lock -> dev_addr_sem -> team_lock

rtnl_newlink
  rtnl_lock
    do_setlink IFLA_ADDRESS on upper
      dev_addr_sem
        netif_set_mac_address
          team_set_mac_address
            team_lock

4. rtnl_lock -> netdev_ops -> dev_addr_sem

rtnl_lock
  dev_ifsioc
    dev_set_mac_address_user

__tun_chr_ioctl
  rtnl_lock
    dev_set_mac_address_user

tap_ioctl
  rtnl_lock
    dev_set_mac_address_user

dev_set_mac_address_user
  netdev_lock_ops
    netif_set_mac_address_user
      dev_addr_sem

v2:
- move lock reorder to happen after kmalloc (Kuniyuki)

Cc: Kohei Enju <enjuk@amazon.com>
Fixes: df43d8bf1031 ("net: replace dev_addr_sem with netdev instance lock")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
---
 include/linux/netdevice.h |  2 --
 net/core/dev.c            | 11 -----------
 net/core/dev_api.c        |  4 +++-
 net/core/rtnetlink.c      | 15 +++++++++++++--
 4 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 42c75cb028e7..2bf1f914f61a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4198,8 +4198,6 @@ int netif_set_mac_address(struct net_device *dev, struct sockaddr *sa,
 			  struct netlink_ext_ack *extack);
 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
 			struct netlink_ext_ack *extack);
-int netif_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
-			       struct netlink_ext_ack *extack);
 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
 			     struct netlink_ext_ack *extack);
 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name);
diff --git a/net/core/dev.c b/net/core/dev.c
index 5a64389461e2..66290c159ad8 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -9592,17 +9592,6 @@ int netif_set_mac_address(struct net_device *dev, struct sockaddr *sa,
 
 DECLARE_RWSEM(dev_addr_sem);
 
-int netif_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
-			       struct netlink_ext_ack *extack)
-{
-	int ret;
-
-	down_write(&dev_addr_sem);
-	ret = netif_set_mac_address(dev, sa, extack);
-	up_write(&dev_addr_sem);
-	return ret;
-}
-
 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name)
 {
 	size_t size = sizeof(sa->sa_data_min);
diff --git a/net/core/dev_api.c b/net/core/dev_api.c
index 2e17548af685..8dbc60612100 100644
--- a/net/core/dev_api.c
+++ b/net/core/dev_api.c
@@ -89,9 +89,11 @@ int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
 {
 	int ret;
 
+	down_write(&dev_addr_sem);
 	netdev_lock_ops(dev);
-	ret = netif_set_mac_address_user(dev, sa, extack);
+	ret = netif_set_mac_address(dev, sa, extack);
 	netdev_unlock_ops(dev);
+	up_write(&dev_addr_sem);
 
 	return ret;
 }
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 9355058bf996..5a24a30dfc2d 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3088,13 +3088,24 @@ static int do_setlink(const struct sk_buff *skb, struct net_device *dev,
 			goto errout;
 		}
 		sa->sa_family = dev->type;
+
+		netdev_unlock_ops(dev);
+
+		/* dev_addr_sem is an outer lock, enforce proper ordering */
+		down_write(&dev_addr_sem);
+		netdev_lock_ops(dev);
+
 		memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
 		       dev->addr_len);
-		err = netif_set_mac_address_user(dev, sa, extack);
+		err = netif_set_mac_address(dev, sa, extack);
 		kfree(sa);
-		if (err)
+		if (err) {
+			up_write(&dev_addr_sem);
 			goto errout;
+		}
 		status |= DO_SETLINK_MODIFIED;
+
+		up_write(&dev_addr_sem);
 	}
 
 	if (tb[IFLA_MTU]) {
-- 
2.48.1

From: Stanislav Fomichev <sdf@fomichev.me>
Date: Wed, 12 Mar 2025 12:05:13 -0700
> Lockdep complains about circular lock in 1 -> 2 -> 3 (see below).
> 
> Change the lock ordering to be:
> - rtnl_lock
> - dev_addr_sem
> - netdev_ops (only for lower devices!)
> - team_lock (or other per-upper device lock)
> 
> 1. rtnl_lock -> netdev_ops -> dev_addr_sem
> 
> rtnl_setlink
>   rtnl_lock
>     do_setlink IFLA_ADDRESS on lower
>       netdev_ops
>         dev_addr_sem
> 
> 2. rtnl_lock -> team_lock -> netdev_ops
> 
> rtnl_newlink
>   rtnl_lock
>     do_setlink IFLA_MASTER on lower
>       do_set_master
>         team_add_slave
>           team_lock
>             team_port_add
> 	      dev_set_mtu
> 	        netdev_ops
> 
> 3. rtnl_lock -> dev_addr_sem -> team_lock
> 
> rtnl_newlink
>   rtnl_lock
>     do_setlink IFLA_ADDRESS on upper
>       dev_addr_sem
>         netif_set_mac_address
>           team_set_mac_address
>             team_lock
> 
> 4. rtnl_lock -> netdev_ops -> dev_addr_sem
> 
> rtnl_lock
>   dev_ifsioc
>     dev_set_mac_address_user
> 
> __tun_chr_ioctl
>   rtnl_lock
>     dev_set_mac_address_user
> 
> tap_ioctl
>   rtnl_lock
>     dev_set_mac_address_user
> 
> dev_set_mac_address_user
>   netdev_lock_ops
>     netif_set_mac_address_user
>       dev_addr_sem
> 
> v2:
> - move lock reorder to happen after kmalloc (Kuniyuki)

My intention was move kmalloc() and memcpy() out of both
netdev_lock and dev_addr_sem like

  netdev_ops_unlock()
  kmalloc()
  memcpy()
  down_write()

, but not a big deal :)

> 
> Cc: Kohei Enju <enjuk@amazon.com>
> Fixes: df43d8bf1031 ("net: replace dev_addr_sem with netdev instance lock")
> Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>