============================================ WARNING: possible recursive locking detected 5.14.0-rc7-next-20210826-syzkaller #0 Not tainted -------------------------------------------- syz-executor.0/11978 is trying to acquire lock: ffff888075c80cf8 (team->team_lock_key){+.+.}-{3:3}, at: team_port_change_check drivers/net/team/team.c:2970 [inline] ffff888075c80cf8 (team->team_lock_key){+.+.}-{3:3}, at: team_device_event+0x1af/0xa90 drivers/net/team/team.c:2993 but task is already holding lock: ffff888075c80cf8 (team->team_lock_key){+.+.}-{3:3}, at: team_add_slave+0x9f/0x1cc0 drivers/net/team/team.c:1966 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(team->team_lock_key); lock(team->team_lock_key); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz-executor.0/11978: #0: ffffffff8d0e5268 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d0e5268 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5568 #1: ffff888075c80cf8 (team->team_lock_key){+.+.}-{3:3}, at: team_add_slave+0x9f/0x1cc0 drivers/net/team/team.c:1966 stack backtrace: CPU: 1 PID: 11978 Comm: syz-executor.0 Not tainted 5.14.0-rc7-next-20210826-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2944 [inline] check_deadlock kernel/locking/lockdep.c:2987 [inline] validate_chain kernel/locking/lockdep.c:3776 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __mutex_lock_common kernel/locking/mutex.c:596 [inline] __mutex_lock+0x131/0x12f0 kernel/locking/mutex.c:729 team_port_change_check drivers/net/team/team.c:2970 [inline] team_device_event+0x1af/0xa90 drivers/net/team/team.c:2993 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1996 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] __dev_notify_flags+0x110/0x2b0 net/core/dev.c:8795 dev_change_flags+0x112/0x170 net/core/dev.c:8833 vlan_device_event+0x1526/0x2020 net/8021q/vlan.c:475 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1996 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] dev_open net/core/dev.c:1525 [inline] dev_open+0x132/0x150 net/core/dev.c:1513 team_port_add drivers/net/team/team.c:1210 [inline] team_add_slave+0xaa4/0x1cc0 drivers/net/team/team.c:1967 do_set_master+0x1c8/0x220 net/core/rtnetlink.c:2521 do_setlink+0x99a/0x3900 net/core/rtnetlink.c:2725 __rtnl_newlink+0xde6/0x1750 net/core/rtnetlink.c:3390 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3505 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2406 ___sys_sendmsg+0xf3/0x170 net/socket.c:2460 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2489 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbee2b1d188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000009 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffe0134836f R14: 00007fbee2b1d300 R15: 0000000000022000