device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
============================================
WARNING: possible recursive locking detected
5.8.0-rc4-syzkaller #0 Not tainted
--------------------------------------------
kworker/u4:4/429 is trying to acquire lock:
ffff88804f606280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4243 [inline]
ffff88804f606280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0xad/0x190 net/core/dev_addr_lists.c:870

but task is already holding lock:
ffff888041c36280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4243 [inline]
ffff888041c36280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xca/0x1b0 net/core/dev_addr_lists.c:925

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&vlan_netdev_addr_lock_key/1);
  lock(&vlan_netdev_addr_lock_key/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

6 locks held by kworker/u4:4/429:
 #0: ffff88821b02f938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x6f4/0xfc0 kernel/workqueue.c:2242
 #1: ffffc90002507d80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x733/0xfc0 kernel/workqueue.c:2244
 #2: ffffffff895b8cf0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xac/0xba0 net/core/net_namespace.c:565
 #3: ffffffff895ba9e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:10549 [inline]
 #3: ffffffff895ba9e8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x124/0x6b0 net/core/dev.c:10587
 #4: ffff8880902a8280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:358 [inline]
 #4: ffff8880902a8280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: netif_addr_lock_bh include/linux/netdevice.h:4248 [inline]
 #4: ffff8880902a8280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_mc_unsync+0x8d/0x1b0 net/core/dev_addr_lists.c:924
 #5: ffff888041c36280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4243 [inline]
 #5: ffff888041c36280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xca/0x1b0 net/core/dev_addr_lists.c:925

stack backtrace:
CPU: 0 PID: 429 Comm: kworker/u4:4 Not tainted 5.8.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1f0/0x31e lib/dump_stack.c:118
 print_deadlock_bug kernel/locking/lockdep.c:2391 [inline]
 check_deadlock kernel/locking/lockdep.c:2432 [inline]
 validate_chain+0x69f2/0x8920 kernel/locking/lockdep.c:3202
 __lock_acquire+0x116c/0x2c30 kernel/locking/lockdep.c:4380
 lock_acquire+0x160/0x720 kernel/locking/lockdep.c:4959
 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:361
 netif_addr_lock_nested include/linux/netdevice.h:4243 [inline]
 dev_mc_sync+0xad/0x190 net/core/dev_addr_lists.c:870
 vlan_dev_set_rx_mode+0x47/0x70 net/8021q/vlan_dev.c:487
 dev_mc_unsync+0x105/0x1b0 net/core/dev_addr_lists.c:927
 vlan_dev_stop+0x47/0x320 net/8021q/vlan_dev.c:315
 __dev_close_many+0x2b2/0x390 net/core/dev.c:1599
 dev_close_many+0x1c1/0x4d0 net/core/dev.c:1624
 rollback_registered_many+0x46d/0x14a0 net/core/dev.c:8945
 unregister_netdevice_many net/core/dev.c:10113 [inline]
 default_device_exit_batch+0x42f/0x6b0 net/core/dev.c:10596
 ops_exit_list net/core/net_namespace.c:189 [inline]
 cleanup_net+0x79c/0xba0 net/core/net_namespace.c:603
 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269
 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415
 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
device veth1_macvtap left promiscuous mode
device veth0_macvtap left promiscuous mode
device veth1_vlan left promiscuous mode
device veth0_vlan left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): Released all slaves