INFO: task kworker/0:0:30892 blocked for more than 143 seconds. Not tainted 5.3.0+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D27888 30892 2 0x80004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x76e/0x17d0 kernel/sched/core.c:4056 schedule+0xd9/0x260 kernel/sched/core.c:4123 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4182 __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 syz-executor.4:30322 blocked for more than 143 seconds. Not tainted 5.3.0+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28712 30322 8781 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x76e/0x17d0 kernel/sched/core.c:4056 schedule+0xd9/0x260 kernel/sched/core.c:4123 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4182 __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 sock_do_ioctl+0x24e/0x2f0 net/socket.c:1051 sock_ioctl+0x3ed/0x780 net/socket.c:1189 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a09 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <90> 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00007f8eb8958c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000007 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8eb89596d4 R13: 00000000004c33ae R14: 00000000004d6cc8 R15: 00000000ffffffff INFO: task syz-executor.0:30338 blocked for more than 143 seconds. Not tainted 5.3.0+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27408 30338 8771 0x00004006 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x76e/0x17d0 kernel/sched/core.c:4056 schedule+0xd9/0x260 kernel/sched/core.c:4123 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4182 __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 get_signal+0x2078/0x2500 kernel/signal.c:2528 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159 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: 0033:0x459a09 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <90> 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00007f237a00ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000020000000 RSI: 00000000400454ca RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f237a00b6d4 R13: 00000000004c4556 R14: 00000000004d89c0 R15: 00000000ffffffff INFO: task syz-executor.2:30341 blocked for more than 144 seconds. Not tainted 5.3.0+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D27184 30341 18755 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x76e/0x17d0 kernel/sched/core.c:4056 schedule+0xd9/0x260 kernel/sched/core.c:4123 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline] synchronize_rcu_expedited+0x57f/0x5f0 kernel/rcu/tree_exp.h:817 synchronize_net+0x3b/0x60 net/core/dev.c:9319 tun_detach_all+0x3d4/0x840 drivers/net/tun.c:768 tun_net_uninit+0x16/0x20 drivers/net/tun.c:1012 rollback_registered_many+0x9bd/0xdd0 net/core/dev.c:8268 rollback_registered+0x109/0x1d0 net/core/dev.c:8296 unregister_netdevice_queue net/core/dev.c:9345 [inline] unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9338 unregister_netdevice include/linux/netdevice.h:2644 [inline] __tun_detach+0xd8a/0x1040 drivers/net/tun.c:723 tun_detach drivers/net/tun.c:740 [inline] tun_chr_close+0xe0/0x180 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: 0033:0x4136f1 Code: 48 89 d0 4c 89 ea 49 89 cf 48 89 f1 4c 89 fe 49 89 c5 48 83 e0 0f 48 0d f0 00 00 00 4c 8d 71 04 49 39 de 0f 83 08 01 00 00 88 <07> 49 c1 ed 04 4c 39 c2 74 5f 48 83 fe 08 73 4a 0f b6 02 49 89 ce RSP: 002b:00007ffefb152eb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00000000004136f1 RDX: 0000001b2f320000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000f18c9049 R09: ffffffffffffffff R10: 00007ffefb152f90 R11: 0000000000000293 R12: 000000000075bf20 R13: 00000000001b2f76 R14: 00000000007606f0 R15: 000000000075bf2c INFO: task syz-executor.3:30359 blocked for more than 144 seconds. Not tainted 5.3.0+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D29720 30359 8779 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x76e/0x17d0 kernel/sched/core.c:4056 schedule+0xd9/0x260 kernel/sched/core.c:4123 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4182 __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 sock_do_ioctl+0x24e/0x2f0 net/socket.c:1051 sock_ioctl+0x3ed/0x780 net/socket.c:1189 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a09 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <90> 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00007fdf8915dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000005 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdf8915e6d4 R13: 00000000004c33ae R14: 00000000004d6cc8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1065: #0: ffffffff88fab280 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/8641: #0: ffff8880a99cc860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8731: #0: ffff88808d644f10 (&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/8732: #0: ffff888097baa650 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8733: #0: ffff88808db496d0 (&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/8734: #0: ffff88808fd80690 (&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 2 locks held by getty/8735: #0: ffff8880a744cad0 (&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/8736: #0: ffff88808dfd2590 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8737: #0: ffff8880a9981590 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f012e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 3 locks held by kworker/1:1/29133: #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff888216ab5be8 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff88809665fdc0 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/0:0/30892: #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: ffff888095d2fdc0 ((linkwatch_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/1:3/7565: #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: ffff888098a2fdc0 (deferred_process_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.0/27639: #0: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.4/30322: #0: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.0/30338: #0: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.2/30341: #0: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.3/30359: #0: ffffffff8999dfe0 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1065 Comm: khungtaskd Not tainted 5.3.0+ #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 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60