====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc2-syzkaller-gc72692105976 #0 Not tainted ------------------------------------------------------ kworker/u8:9/4423 is trying to acquire lock: ffff0000ee6ace00 (team->team_lock_key#4){+.+.}-{4:4}, at: team_port_change_check+0x5c/0x228 drivers/net/team/team_core.c:2966 but task is already holding lock: ffff0000ee664d30 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] ffff0000ee664d30 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] ffff0000ee664d30 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x4b8/0x210c net/core/dev.c:11938 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&dev_instance_lock_key#3){+.+.}-{4:4}: __mutex_lock_common+0x1f0/0x2604 kernel/locking/mutex.c:601 __mutex_lock kernel/locking/mutex.c:746 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:798 netdev_lock include/linux/netdevice.h:2751 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] dev_set_mtu+0xfc/0x214 net/core/dev_api.c:246 team_port_add drivers/net/team/team_core.c:1215 [inline] team_add_slave+0x64c/0x221c drivers/net/team/team_core.c:1989 do_set_master+0x42c/0x5bc net/core/rtnetlink.c:2946 do_setlink+0xc90/0x385c net/core/rtnetlink.c:3159 rtnl_changelink net/core/rtnetlink.c:3772 [inline] __rtnl_newlink net/core/rtnetlink.c:3931 [inline] rtnl_newlink+0x123c/0x185c net/core/rtnetlink.c:4068 rtnetlink_rcv_msg+0x670/0xa9c net/core/rtnetlink.c:6958 netlink_rcv_skb+0x234/0x408 net/netlink/af_netlink.c:2534 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6985 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x668/0x8a4 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x708/0xaa4 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] ____sys_sendmsg+0x578/0x890 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmsg+0x238/0x304 net/socket.c:2652 __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2655 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #0 (team->team_lock_key#4){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x17b8/0x32c4 kernel/locking/lockdep.c:5235 lock_acquire+0x150/0x2e8 kernel/locking/lockdep.c:5866 __mutex_lock_common+0x1f0/0x2604 kernel/locking/mutex.c:601 __mutex_lock kernel/locking/mutex.c:746 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:798 team_port_change_check+0x5c/0x228 drivers/net/team/team_core.c:2966 team_device_event+0x1b8/0x4d4 drivers/net/team/team_core.c:-1 notifier_call_chain+0x1c4/0x550 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info net/core/dev.c:2174 [inline] call_netdevice_notifiers_extack net/core/dev.c:2212 [inline] call_netdevice_notifiers net/core/dev.c:2226 [inline] dev_close_many+0x308/0x474 net/core/dev.c:1729 unregister_netdevice_many_notify+0x52c/0x210c net/core/dev.c:11940 unregister_netdevice_many net/core/dev.c:12035 [inline] default_device_exit_batch+0x904/0x984 net/core/dev.c:12527 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x6c4/0xa48 net/core/net_namespace.c:654 process_one_work+0x810/0x1638 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x97c/0xf08 kernel/workqueue.c:3400 kthread+0x674/0x7dc kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&dev_instance_lock_key#3); lock(team->team_lock_key#4); lock(&dev_instance_lock_key#3); lock(team->team_lock_key#4); *** DEADLOCK *** 5 locks held by kworker/u8:9/4423: #0: ffff0000c183a148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x674/0x1638 kernel/workqueue.c:3212 #1: ffff8000a0277b80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x708/0x1638 kernel/workqueue.c:3212 #2: ffff800093064d50 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x148/0xa48 net/core/net_namespace.c:608 #3: ffff800093071868 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 #4: ffff0000ee664d30 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] #4: ffff0000ee664d30 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #4: ffff0000ee664d30 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x4b8/0x210c net/core/dev.c:11938 stack backtrace: CPU: 1 UID: 0 PID: 4423 Comm: kworker/u8:9 Not tainted 6.15.0-rc2-syzkaller-gc72692105976 #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: netns cleanup_net Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 dump_stack+0x1c/0x1028 lib/dump_stack.c:129 print_circular_bug+0x32c/0x334 kernel/locking/lockdep.c:2079 check_noncircular+0x15c/0x178 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x17b8/0x32c4 kernel/locking/lockdep.c:5235 lock_acquire+0x150/0x2e8 kernel/locking/lockdep.c:5866 __mutex_lock_common+0x1f0/0x2604 kernel/locking/mutex.c:601 __mutex_lock kernel/locking/mutex.c:746 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:798 team_port_change_check+0x5c/0x228 drivers/net/team/team_core.c:2966 team_device_event+0x1b8/0x4d4 drivers/net/team/team_core.c:-1 notifier_call_chain+0x1c4/0x550 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info net/core/dev.c:2174 [inline] call_netdevice_notifiers_extack net/core/dev.c:2212 [inline] call_netdevice_notifiers net/core/dev.c:2226 [inline] dev_close_many+0x308/0x474 net/core/dev.c:1729 unregister_netdevice_many_notify+0x52c/0x210c net/core/dev.c:11940 unregister_netdevice_many net/core/dev.c:12035 [inline] default_device_exit_batch+0x904/0x984 net/core/dev.c:12527 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x6c4/0xa48 net/core/net_namespace.c:654 process_one_work+0x810/0x1638 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x97c/0xf08 kernel/workqueue.c:3400 kthread+0x674/0x7dc kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 team0 (unregistering): Port device team_slave_1 removed team0 (unregistering): Port device team_slave_0 removed team0 (unregistering): Port device dummy0 removed