====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc2-syzkaller-00682-gcd7276ecac9c #0 Not tainted ------------------------------------------------------ syz.3.484/7917 is trying to acquire lock: ffff88803195ce00 (team->team_lock_key#5){+.+.}-{4:4}, at: team_port_change_check+0x51/0x1e0 drivers/net/team/team_core.c:2966 but task is already holding lock: ffff8880558ecd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2750 [inline] ffff8880558ecd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x5ac/0x2640 net/core/dev.c:11995 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&dev_instance_lock_key#20){+.+.}-{4:4}: lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 netdev_lock include/linux/netdevice.h:2750 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] dev_set_mtu+0x11c/0x270 net/core/dev_api.c:246 team_port_add drivers/net/team/team_core.c:1215 [inline] team_add_slave+0x83b/0x28b0 drivers/net/team/team_core.c:1989 do_set_master+0x579/0x730 net/core/rtnetlink.c:2946 do_setlink+0xf76/0x4390 net/core/rtnetlink.c:3159 rtnl_changelink net/core/rtnetlink.c:3770 [inline] __rtnl_newlink net/core/rtnetlink.c:3929 [inline] rtnl_newlink+0x17e2/0x1fe0 net/core/rtnetlink.c:4066 rtnetlink_rcv_msg+0x80f/0xd70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8c3/0xcd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:727 ____sys_sendmsg+0x523/0x860 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmsg+0x271/0x360 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (team->team_lock_key#5){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 team_port_change_check+0x51/0x1e0 drivers/net/team/team_core.c:2966 team_device_event+0x161/0x5b0 drivers/net/team/team_core.c:2992 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline] call_netdevice_notifiers net/core/dev.c:2280 [inline] dev_close_many+0x33e/0x4c0 net/core/dev.c:1783 unregister_netdevice_many_notify+0x631/0x2640 net/core/dev.c:11998 unregister_netdevice_many net/core/dev.c:12099 [inline] unregister_netdevice_queue+0x383/0x400 net/core/dev.c:11943 unregister_netdevice include/linux/netdevice.h:3373 [inline] nsim_destroy+0x21e/0x690 drivers/net/netdevsim/netdev.c:1064 __nsim_dev_port_del+0x14b/0x1b0 drivers/net/netdevsim/dev.c:1428 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1440 [inline] nsim_dev_reload_destroy+0x28a/0x490 drivers/net/netdevsim/dev.c:1661 nsim_dev_reload_down+0x98/0xd0 drivers/net/netdevsim/dev.c:968 devlink_reload+0x1ac/0x8c0 net/devlink/dev.c:461 devlink_nl_reload_doit+0xa58/0xed0 net/devlink/dev.c:584 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb38/0xf00 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8c3/0xcd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:727 ____sys_sendmsg+0x523/0x860 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmsg+0x271/0x360 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&dev_instance_lock_key#20); lock(team->team_lock_key#5); lock(&dev_instance_lock_key#20); lock(team->team_lock_key#5); *** DEADLOCK *** 5 locks held by syz.3.484/7917: #0: ffffffff90163650 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffff88807ea150e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #1: ffff88807ea150e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #1: ffff88807ea150e8 (&dev->mutex){....}-{4:4}, at: devlink_get_from_attrs_lock+0x266/0x410 net/devlink/netlink.c:198 #2: ffff88807ea16250 (&devlink->lock_key#5){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #2: ffff88807ea16250 (&devlink->lock_key#5){+.+.}-{4:4}, at: devlink_get_from_attrs_lock+0x275/0x410 net/devlink/netlink.c:198 #3: ffffffff900fe988 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x10d/0x690 drivers/net/netdevsim/netdev.c:1059 #4: ffff8880558ecd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2750 [inline] #4: ffff8880558ecd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x5ac/0x2640 net/core/dev.c:11995 stack backtrace: CPU: 0 UID: 0 PID: 7917 Comm: syz.3.484 Not tainted 6.15.0-rc2-syzkaller-00682-gcd7276ecac9c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2079 check_noncircular+0x142/0x160 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+0xa69/0x24e0 kernel/locking/lockdep.c:3909 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 team_port_change_check+0x51/0x1e0 drivers/net/team/team_core.c:2966 team_device_event+0x161/0x5b0 drivers/net/team/team_core.c:2992 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline] call_netdevice_notifiers net/core/dev.c:2280 [inline] dev_close_many+0x33e/0x4c0 net/core/dev.c:1783 unregister_netdevice_many_notify+0x631/0x2640 net/core/dev.c:11998 unregister_netdevice_many net/core/dev.c:12099 [inline] unregister_netdevice_queue+0x383/0x400 net/core/dev.c:11943 unregister_netdevice include/linux/netdevice.h:3373 [inline] nsim_destroy+0x21e/0x690 drivers/net/netdevsim/netdev.c:1064 __nsim_dev_port_del+0x14b/0x1b0 drivers/net/netdevsim/dev.c:1428 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1440 [inline] nsim_dev_reload_destroy+0x28a/0x490 drivers/net/netdevsim/dev.c:1661 nsim_dev_reload_down+0x98/0xd0 drivers/net/netdevsim/dev.c:968 devlink_reload+0x1ac/0x8c0 net/devlink/dev.c:461 devlink_nl_reload_doit+0xa58/0xed0 net/devlink/dev.c:584 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb38/0xf00 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8c3/0xcd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:727 ____sys_sendmsg+0x523/0x860 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmsg+0x271/0x360 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa8cdf8e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa8ceeda038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa8ce1b5fa0 RCX: 00007fa8cdf8e969 RDX: 0000000004000084 RSI: 0000200000000100 RDI: 0000000000000005 RBP: 00007fa8ce010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa8ce1b5fa0 R15: 00007ffd404230f8 team0: Port device netdevsim0 removed