batman_adv: batadv0: Interface deactivated: batadv_slave_1 batman_adv: batadv0: Removing interface: batadv_slave_1 bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state ============================================ WARNING: possible recursive locking detected 5.8.0-rc2-syzkaller #0 Not tainted -------------------------------------------- kworker/u4:8/10540 is trying to acquire lock: ffff88805d320280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4243 [inline] ffff88805d320280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync net/core/dev_addr_lists.c:915 [inline] ffff88805d320280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xf4/0x190 net/core/dev_addr_lists.c:909 but task is already holding lock: ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:358 [inline] ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_bh include/linux/netdevice.h:4248 [inline] ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync net/core/dev_addr_lists.c:914 [inline] ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xb0/0x190 net/core/dev_addr_lists.c:909 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 5 locks held by kworker/u4:8/10540: #0: ffff8880a97ad138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a97ad138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880a97ad138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880a97ad138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880a97ad138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880a97ad138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90002667da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8a7a3a70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565 #3: ffffffff8a7b08e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:10557 [inline] #3: ffffffff8a7b08e8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xea/0x3d0 net/core/dev.c:10595 #4: ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:358 [inline] #4: ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_bh include/linux/netdevice.h:4248 [inline] #4: ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync net/core/dev_addr_lists.c:914 [inline] #4: ffff88805dc60280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xb0/0x190 net/core/dev_addr_lists.c:909 stack backtrace: CPU: 1 PID: 10540 Comm: kworker/u4:8 Not tainted 5.8.0-rc2-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+0x18f/0x20d lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:2391 [inline] check_deadlock kernel/locking/lockdep.c:2432 [inline] validate_chain kernel/locking/lockdep.c:3202 [inline] __lock_acquire.cold+0x178/0x3f8 kernel/locking/lockdep.c:4380 lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:4959 _raw_spin_lock_nested+0x30/0x40 kernel/locking/spinlock.c:361 netif_addr_lock_nested include/linux/netdevice.h:4243 [inline] dev_mc_unsync net/core/dev_addr_lists.c:915 [inline] dev_mc_unsync+0xf4/0x190 net/core/dev_addr_lists.c:909 vlan_dev_stop+0x51/0x350 net/8021q/vlan_dev.c:315 __dev_close_many+0x1b3/0x2e0 net/core/dev.c:1605 dev_close_many+0x238/0x650 net/core/dev.c:1630 rollback_registered_many+0x3af/0xf60 net/core/dev.c:8953 unregister_netdevice_many.part.0+0x1a/0x2f0 net/core/dev.c:10121 unregister_netdevice_many net/core/dev.c:10120 [inline] default_device_exit_batch+0x30c/0x3d0 net/core/dev.c:10604 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189 cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 bond12 (unregistering): (slave bridge14): Releasing backup interface device bridge14 left promiscuous mode bond12 (unregistering): Released all slaves bond11 (unregistering): (slave bridge9): Releasing backup interface bond11 (unregistering): (slave bridge8): Removing an active aggregator bond11 (unregistering): (slave bridge8): Releasing backup interface bond11 (unregistering): Released all slaves bond10 (unregistering): Released all slaves bond9 (unregistering): Released all slaves bond8 (unregistering): (slave bridge6): Releasing backup interface bond8 (unregistering): (slave bridge5): Releasing backup interface bond8 (unregistering): Released all slaves bond7 (unregistering): Released all slaves bond6 (unregistering): Released all slaves bond5 (unregistering): Released all slaves bond4 (unregistering): Released all slaves bond3 (unregistering): Released all slaves bond2 (unregistering): Released all slaves bond1 (unregistering): Released all slaves 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