INFO: task kworker/u4:5:10771 blocked for more than 140 seconds. Not tainted 4.20.0-rc6+ #149 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:5 D13104 10771 2 0x80000000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 netdev_run_todo+0x6ae/0xa60 net/core/dev.c:8802 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:117 ip_tunnel_delete_nets+0x4d7/0x6d0 net/ipv4/ip_tunnel.c:1083 ipgre_exit_batch_net+0x22/0x30 net/ipv4/ip_gre.c:1060 ops_exit_list.isra.5+0x105/0x160 net/core/net_namespace.c:156 cleanup_net+0x555/0xb10 net/core/net_namespace.c:551 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:0:27593 blocked for more than 140 seconds. Not tainted 4.20.0-rc6+ #149 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D19896 27593 2 0x80000000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:150 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:4:17344 blocked for more than 140 seconds. Not tainted 4.20.0-rc6+ #149 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:4 D22584 17344 2 0x80000000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4481 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task syz-executor2:28843 blocked for more than 140 seconds. Not tainted 4.20.0-rc6+ #149 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D22352 28843 20828 0x80000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 exp_funnel_lock kernel/rcu/tree_exp.h:319 [inline] _synchronize_rcu_expedited.constprop.58+0x8df/0x9d0 kernel/rcu/tree_exp.h:620 synchronize_rcu_expedited+0x27/0xa0 kernel/rcu/tree_exp.h:758 synchronize_net+0x3b/0x60 net/core/dev.c:9074 tipc_nametbl_stop+0x968/0xca0 net/tipc/name_table.c:797 tipc_exit_net+0x2d/0x40 net/tipc/core.c:103 ops_exit_list.isra.5+0xb0/0x160 net/core/net_namespace.c:153 setup_net+0x501/0x8d0 net/core/net_namespace.c:331 copy_net_ns+0x2b1/0x4a0 net/core/net_namespace.c:437 create_new_namespaces+0x6ad/0x900 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x79c/0x10b0 kernel/fork.c:2539 __do_sys_unshare kernel/fork.c:2607 [inline] __se_sys_unshare kernel/fork.c:2605 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2605 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457659 Code: fc ff 48 8b 44 24 08 48 8b 08 48 89 0c 24 e8 ee 27 fc ff e8 39 78 fc ff 48 8b 44 24 08 e9 95 fe ff ff e8 5a 28 00 00 e9 45 fe ff cc cc cc cc cc 48 8b 4c 24 10 48 8b 11 64 48 8b 1c 25 f8 ff RSP: 002b:00007f0a4983ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000457659 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0a4983f6d4 R13: 00000000004c5a72 R14: 00000000004da238 R15: 00000000ffffffff INFO: task syz-executor3:28833 blocked for more than 140 seconds. Not tainted 4.20.0-rc6+ #149 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D20920 28833 20511 0x80000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 exp_funnel_lock kernel/rcu/tree_exp.h:319 [inline] _synchronize_rcu_expedited.constprop.58+0x8df/0x9d0 kernel/rcu/tree_exp.h:620 synchronize_rcu_expedited+0x27/0xa0 kernel/rcu/tree_exp.h:758 synchronize_net+0x3b/0x60 net/core/dev.c:9074 dev_deactivate_many+0x543/0xdd0 net/sched/sch_generic.c:1222 __dev_close_many+0x197/0x380 net/core/dev.c:1461 dev_close_many+0x2df/0x860 net/core/dev.c:1499 rollback_registered_many+0x543/0x1250 net/core/dev.c:7991 unregister_netdevice_many+0xfa/0x4c0 net/core/dev.c:9119 ip_tunnel_delete_nets+0x4d2/0x6d0 net/ipv4/ip_tunnel.c:1082 ipgre_tap_exit_batch_net+0x22/0x30 net/ipv4/ip_gre.c:1644 ops_exit_list.isra.5+0x105/0x160 net/core/net_namespace.c:156 setup_net+0x501/0x8d0 net/core/net_namespace.c:331 copy_net_ns+0x2b1/0x4a0 net/core/net_namespace.c:437 create_new_namespaces+0x6ad/0x900 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x79c/0x10b0 kernel/fork.c:2539 __do_sys_unshare kernel/fork.c:2607 [inline] __se_sys_unshare kernel/fork.c:2605 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2605 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457659 Code: fc ff 48 8b 44 24 08 48 8b 08 48 89 0c 24 e8 ee 27 fc ff e8 39 78 fc ff 48 8b 44 24 08 e9 95 fe ff ff e8 5a 28 00 00 e9 45 fe ff cc cc cc cc cc 48 8b 4c 24 10 48 8b 11 64 48 8b 1c 25 f8 ff RSP: 002b:00007f3c18bdfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000457659 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3c18be06d4 R13: 00000000004c5a72 R14: 00000000004da238 R15: 00000000ffffffff INFO: task syz-executor3:28846 blocked for more than 140 seconds. Not tainted 4.20.0-rc6+ #149 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D21456 28846 20511 0x80000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 tc_action_net_exit include/net/act_api.h:133 [inline] tunnel_key_exit_net+0x7d/0x450 net/sched/act_tunnel_key.c:580 ops_exit_list.isra.5+0x105/0x160 net/core/net_namespace.c:156 setup_net+0x501/0x8d0 net/core/net_namespace.c:331 copy_net_ns+0x2b1/0x4a0 net/core/net_namespace.c:437 create_new_namespaces+0x6ad/0x900 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x79c/0x10b0 kernel/fork.c:2539 __do_sys_unshare kernel/fork.c:2607 [inline] __se_sys_unshare kernel/fork.c:2605 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2605 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457659 Code: fc ff 48 8b 44 24 08 48 8b 08 48 89 0c 24 e8 ee 27 fc ff e8 39 78 fc ff 48 8b 44 24 08 e9 95 fe ff ff e8 5a 28 00 00 e9 45 fe ff cc cc cc cc cc 48 8b 4c 24 10 48 8b 11 64 48 8b 1c 25 f8 ff RSP: 002b:00007f3c18bbec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000457659 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3c18bbf6d4 R13: 00000000004c5a72 R14: 00000000004da238 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1018: #0: 000000007f29209b (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 2 locks held by rsyslogd/5900: #0: 00000000dfe3fccb (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 00000000fcdd7326 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1124 [inline] #1: 00000000fcdd7326 (&rq->lock){-.-.}, at: __schedule+0x236/0x21d0 kernel/sched/core.c:3410 2 locks held by getty/5991: #0: 000000001ba5639f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000006369a1b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5992: #0: 00000000f85a7427 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000005961a168 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5993: #0: 00000000cf8cf974 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000cb706d75 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5994: #0: 00000000fdd7cab6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000022a36220 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5995: #0: 0000000091fd6ddf (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000009b4c2f5a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5996: #0: 00000000d17959e0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000375f3452 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5997: #0: 000000003ad07008 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000bb974e98 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 4 locks held by kworker/u4:5/10771: #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:209 [inline] #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000006d4da43a ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0xb43/0x1c40 kernel/workqueue.c:2124 #1: 0000000049ba1eb4 (net_cleanup_work){+.+.}, at: process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128 #2: 000000001545518b (pernet_ops_rwsem){++++}, at: cleanup_net+0x13f/0xb10 net/core/net_namespace.c:518 #3: 000000007bce9571 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/0:0/27593: #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:209 [inline] #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000fccc4aee ((wq_completion)"events"){+.+.}, at: process_one_work+0xb43/0x1c40 kernel/workqueue.c:2124 #1: 000000006956d2cf (deferred_process_work){+.+.}, at: process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128 #2: 000000007bce9571 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/0:4/17344: #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: __write_once_size include/linux/compiler.h:209 [inline] #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000cc904e35 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0xb43/0x1c40 kernel/workqueue.c:2124 #1: 00000000612f72a8 ((addr_chk_work).work){+.+.}, at: process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128 #2: 000000007bce9571 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor2/28843: #0: 000000001545518b (pernet_ops_rwsem){++++}, at: copy_net_ns+0x28c/0x4a0 net/core/net_namespace.c:433 2 locks held by syz-executor3/28833: #0: 000000001545518b (pernet_ops_rwsem){++++}, at: copy_net_ns+0x28c/0x4a0 net/core/net_namespace.c:433 #1: 000000007bce9571 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 2 locks held by syz-executor3/28846: #0: 000000001545518b (pernet_ops_rwsem){++++}, at: copy_net_ns+0x28c/0x4a0 net/core/net_namespace.c:433 #1: 000000007bce9571 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1018 Comm: khungtaskd Not tainted 4.20.0-rc6+ #149 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+0x244/0x39d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e8/0x22a 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+0xb51/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57