============================================ WARNING: possible recursive locking detected 6.12.0-syzkaller #0 Not tainted -------------------------------------------- syz.1.1745/9922 is trying to acquire lock: ffff88807b4d4d40 (team->team_lock_key#3){+.+.}-{3:3}, at: team_port_change_check+0x51/0x1e0 drivers/net/team/team_core.c:2950 but task is already holding lock: ffff88807b4d4d40 (team->team_lock_key#3){+.+.}-{3:3}, at: team_add_slave+0xad/0x2760 drivers/net/team/team_core.c:1975 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(team->team_lock_key#3); lock(team->team_lock_key#3); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz.1.1745/9922: #0: ffffffff8fcc1908 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc1908 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 #1: ffff88807b4d4d40 (team->team_lock_key#3){+.+.}-{3:3}, at: team_add_slave+0xad/0x2760 drivers/net/team/team_core.c:1975 stack backtrace: CPU: 1 UID: 0 PID: 9922 Comm: syz.1.1745 Not tainted 6.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 team_port_change_check+0x51/0x1e0 drivers/net/team/team_core.c:2950 team_device_event+0x4e6/0x5b0 drivers/net/team/team_core.c:2973 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93 __dev_notify_flags+0x207/0x400 dev_change_flags+0xf0/0x1a0 net/core/dev.c:8922 vlan_device_event+0x1b81/0x1de0 net/8021q/vlan.c:468 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline] call_netdevice_notifiers net/core/dev.c:2048 [inline] dev_open+0x13a/0x1b0 net/core/dev.c:1517 team_port_add drivers/net/team/team_core.c:1216 [inline] team_add_slave+0x9c8/0x2760 drivers/net/team/team_core.c:1976 do_set_master net/core/rtnetlink.c:2730 [inline] do_setlink+0xe73/0x41f0 net/core/rtnetlink.c:2936 __rtnl_newlink net/core/rtnetlink.c:3725 [inline] rtnl_newlink+0x180d/0x20a0 net/core/rtnetlink.c:3772 rtnetlink_rcv_msg+0x73f/0xcf0 net/core/rtnetlink.c:6675 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2536 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1342 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1886 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:744 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2607 ___sys_sendmsg net/socket.c:2661 [inline] __sys_sendmsg+0x292/0x380 net/socket.c:2690 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe0a497e759 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:00007fe0a572f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fe0a4b35f80 RCX: 00007fe0a497e759 RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003 RBP: 00007fe0a49f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe0a4b35f80 R15: 00007ffebe5fe2b8