INFO: task kworker/1:3:8745 blocked for more than 143 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D26008 8745 2 0x80004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 linkwatch_event+0xf/0x70 net/core/link_watch.c:242 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:0:15536 blocked for more than 143 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D27000 15536 2 0x80004000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:74 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.4:16935 blocked for more than 143 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D24600 16935 1 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 __sys_sendto+0x262/0x380 net/socket.c:1952 __do_sys_sendto net/socket.c:1964 [inline] __se_sys_sendto net/socket.c:1960 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1960 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf3 Code: 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 db 73 ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 00 00 RSP: 002b:00007fff56c65218 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000413bf3 RDX: 000000000000006c RSI: 0000000000a71df0 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007fff56c65220 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff56c655e0 R13: 00007fff56c652a8 R14: 00007fff56c65370 R15: 00000000004bee80 INFO: task syz-executor.1:16938 blocked for more than 144 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D24600 16938 1 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 __sys_sendto+0x262/0x380 net/socket.c:1952 __do_sys_sendto net/socket.c:1964 [inline] __se_sys_sendto net/socket.c:1960 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1960 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf3 Code: 88 44 1c 30 48 ff c3 48 ff c8 48 89 c6 eb 17 49 89 c0 48 0d 80 00 00 00 88 44 1c 30 49 c1 e8 07 48 ff c3 4c 89 c0 48 3d 80 00 <00> 00 72 0b 48 83 fb 28 72 db e9 22 01 00 00 48 83 fb 28 0f 83 11 RSP: 002b:00007ffc54c12c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000413bf3 RDX: 000000000000003c RSI: 0000000000a71df0 RDI: 0000000000000003 RBP: 00007ffc54c13010 R08: 00007ffc54c12c70 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 00000000004bee80 INFO: task syz-executor.5:16939 blocked for more than 145 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D24600 16939 1 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 __sys_sendto+0x262/0x380 net/socket.c:1952 __do_sys_sendto net/socket.c:1964 [inline] __se_sys_sendto net/socket.c:1960 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1960 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf3 Code: 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 db 73 ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 00 00 RSP: 002b:00007ffdf8cf1688 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000413bf3 RDX: 0000000000000038 RSI: 0000000000a71df0 RDI: 0000000000000003 RBP: 00007ffdf8cf1a30 R08: 00007ffdf8cf1690 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 00000000004bee80 INFO: task syz-executor.0:16961 blocked for more than 146 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28160 16961 12095 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 tun_detach drivers/net/tun.c:737 [inline] tun_chr_close+0x3f/0x180 drivers/net/tun.c:3448 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413a91 Code: 8b 7c 24 30 48 83 c4 38 c3 48 8b 05 f9 9b 24 00 49 8b 55 00 49 83 c4 01 41 b9 cb 2a 44 00 48 89 ee 4c 89 e7 48 85 c0 4c 0f 45 45 31 c0 31 c9 e8 34 50 00 00 85 c0 89 c3 0f 85 7b ff ff ff 31 RSP: 002b:00007ffc46540010 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413a91 RDX: 0000001b2fa20000 RSI: 0000000000000d82 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000e8818d82 R09: 00000000e8818d86 R10: 00007ffc465400f0 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000761590 R15: 000000000075bf2c INFO: task syz-executor.3:16967 blocked for more than 146 seconds. Not tainted 5.4.0-rc1+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28136 16967 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 __sys_sendto+0x262/0x380 net/socket.c:1952 __do_sys_sendto net/socket.c:1964 [inline] __se_sys_sendto net/socket.c:1960 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1960 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf3 Code: 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 db 73 ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 00 00 RSP: 002b:00007ffcbae8f6e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000413bf3 RDX: 0000000000000028 RSI: 0000000000a71df0 RDI: 0000000000000003 RBP: 00007ffcbae8f750 R08: 00007ffcbae8f6f0 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ffcbae8fa58 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1069: #0: ffffffff88faadc0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/8608: #0: ffff88809a943660 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8698: #0: ffff88809bf7a490 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8699: #0: ffff888099492c50 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8700: #0: ffff888087e26d50 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8701: #0: ffff888087e275d0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8702: #0: ffff8880994934d0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f152e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8703: #0: ffff8880990b6cd0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f352e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8704: #0: ffff88809d1d8b50 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 3 locks held by kworker/1:3/8745: #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff8880a79a7dc0 ((linkwatch_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 9 locks held by kworker/u4:5/8817: 2 locks held by kworker/u4:6/9349: 3 locks held by kworker/0:0/15536: #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff888098587dc0 (deferred_process_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/1:17/16895: #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8882165d4168 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff888069b57dc0 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.4/16935: #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 1 lock held by syz-executor.1/16938: #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 1 lock held by syz-executor.5/16939: #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 2 locks held by syz-executor.2/16958: #0: ffffffff89995f48 (pernet_ops_rwsem){++++}, at: copy_net_ns+0x26d/0x420 net/core/net_namespace.c:472 #1: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.0/16961: #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.3/16967: #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff899a31a0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5220 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1069 Comm: khungtaskd Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9d0/0xef0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8817 Comm: kworker/u4:5 Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:io_serial_out+0x73/0x90 drivers/tty/serial/8250/8250_port.c:457 Code: 00 49 8d 7c 24 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 19 41 03 5c 24 38 44 89 e8 89 da ee <5b> 41 5c 41 5d 5d c3 e8 81 34 1e fe eb c0 e8 da 34 1e fe eb e0 0f RSP: 0018:ffff888069dc7458 EFLAGS: 00000002 RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff83903b06 RDI: ffffffff8b57da78 RBP: ffff888069dc7470 R08: ffff888069dbc6c0 R09: ffffed100d3b8e89 R10: ffffed100d3b8e88 R11: 0000000000000003 R12: ffffffff8b57da40 R13: 000000000000005b R14: ffffffff8b57da40 R15: 000000000000005b FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efd10022008 CR3: 000000008eb14000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_out include/linux/serial_core.h:265 [inline] serial8250_console_putchar+0x45/0x60 drivers/tty/serial/8250/8250_port.c:3111 uart_console_write+0x54/0x110 drivers/tty/serial/serial_core.c:1928 serial8250_console_write+0x612/0x9a0 drivers/tty/serial/8250/8250_port.c:3174 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:587 call_console_drivers kernel/printk/printk.c:1791 [inline] console_unlock+0xb89/0xf10 kernel/printk/printk.c:2473 vprintk_emit+0x2a0/0x700 kernel/printk/printk.c:1996 vprintk_default+0x28/0x30 kernel/printk/printk.c:2023 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:386 printk+0xba/0xed kernel/printk/printk.c:2056 kobject_uevent_env+0x1f5/0x101d lib/kobject_uevent.c:496 kobject_uevent+0x20/0x26 lib/kobject_uevent.c:641 kobject_cleanup lib/kobject.c:680 [inline] kobject_release lib/kobject.c:722 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put.cold+0x177/0x2e6 lib/kobject.c:739 netdev_queue_update_kobjects+0x250/0x3d0 net/core/net-sysfs.c:1505 remove_queue_kobjects net/core/net-sysfs.c:1558 [inline] netdev_unregister_kobject+0x15e/0x1f0 net/core/net-sysfs.c:1708 rollback_registered_many+0x7c6/0xfc0 net/core/dev.c:8278 unregister_netdevice_many.part.0+0x1b/0x1f0 net/core/dev.c:9364 unregister_netdevice_many net/core/dev.c:9363 [inline] default_device_exit_batch+0x34e/0x410 net/core/dev.c:9835 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:175 cleanup_net+0x4e7/0xa70 net/core/net_namespace.c:595 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352