INFO: task kworker/u4:14:17138 blocked for more than 143 seconds. Not tainted 5.1.0-rc1 #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:14 D24152 17138 2 0x80000000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_timeout+0x8ca/0xfd0 kernel/time/timer.c:1779 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 flush_workqueue+0x40f/0x14c0 kernel/workqueue.c:2826 rxrpc_destroy_all_connections+0x103/0x487 net/rxrpc/conn_object.c:472 rxrpc_exit_net+0x1c2/0x310 net/rxrpc/net_ns.c:126 ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:153 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:551 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.4:5407 blocked for more than 143 seconds. Not tainted 5.1.0-rc1 #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28368 5407 7914 0x80000002 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 tp_perf_event_destroy+0x16/0x20 kernel/events/core.c:8575 _free_event+0x356/0x13b0 kernel/events/core.c:4453 put_event+0x47/0x60 kernel/events/core.c:4539 perf_event_release_kernel+0x693/0xc60 kernel/events/core.c:4645 perf_release+0x37/0x50 kernel/events/core.c:4655 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:980 __do_sys_exit_group kernel/exit.c:991 [inline] __se_sys_exit_group kernel/exit.c:989 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:989 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458079 Code: Bad RIP value. RSP: 002b:00007ffc72b2ce28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000000458079 RDX: 0000000000411d71 RSI: 0000000000a54ef0 RDI: 0000000000000000 RBP: 00000000004bd682 R08: 000000000000000c R09: 00007ffc72b2cf30 R10: 00000000017d6940 R11: 0000000000000246 R12: 000000000073bfac R13: 0000000000000001 R14: 0000000000000003 R15: 000000000073bfac INFO: task syz-executor.1:5509 blocked for more than 144 seconds. Not tainted 5.1.0-rc1 #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28384 5509 10543 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_timeout+0x8ca/0xfd0 kernel/time/timer.c:1779 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 __synchronize_srcu+0x197/0x250 kernel/rcu/srcutree.c:925 synchronize_srcu_expedited kernel/rcu/srcutree.c:950 [inline] synchronize_srcu+0x239/0x3e8 kernel/rcu/srcutree.c:1001 tracepoint_synchronize_unregister include/linux/tracepoint.h:84 [inline] perf_trace_event_unreg.isra.0+0xcb/0x220 kernel/trace/trace_event_perf.c:163 perf_trace_destroy+0xc1/0x100 kernel/trace/trace_event_perf.c:238 tp_perf_event_destroy+0x16/0x20 kernel/events/core.c:8575 _free_event+0x356/0x13b0 kernel/events/core.c:4453 put_event+0x47/0x60 kernel/events/core.c:4539 perf_event_release_kernel+0x693/0xc60 kernel/events/core.c:4645 perf_release+0x37/0x50 kernel/events/core.c:4655 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x411e31 Code: ec 08 48 85 f6 0f 84 de 00 00 00 48 85 ff 48 89 fd 0f 84 d2 00 00 00 48 c7 06 00 00 00 00 bf 58 30 44 00 b9 08 00 00 00 48 89 f3 a6 74 2a bf 60 30 44 00 b9 09 00 00 00 48 89 ee f3 a6 75 29 RSP: 002b:00007ffc0bd900a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000411e31 RDX: 0000001b2ea20000 RSI: 0000000000740c10 RDI: 0000000000000003 RBP: 0000000000000000 R08: ffffffff8145b125 R09: 000000004cc1c536 R10: 00007ffc0bd8ffd0 R11: 0000000000000293 R12: 0000000000000000 R13: 00007ffc0bd900e0 R14: 0000000000000000 R15: 00007ffc0bd900f0 Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 000000006f13cd88 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5061 1 lock held by rsyslogd/7769: #0: 00000000bb66f1f1 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7860: #0: 000000003cf20ca7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008df7481e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7861: #0: 0000000013e37a90 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000036d1de7b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7862: #0: 00000000579135ed (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000007ae125dd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7863: #0: 00000000d1a8ac57 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000024e3da03 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7864: #0: 0000000025c66722 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ff27b3a2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7865: #0: 00000000e5a01453 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000035bdcdb9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7866: #0: 00000000b542775c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000034c497c6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/10711: #0: 00000000b398aa33 (event_mutex){+.+.}, at: perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 3 locks held by kworker/u4:14/17138: #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000e95476ac ((wq_completion)netns){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 0000000044ee5a28 (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 00000000fbbb12b4 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:518 1 lock held by syz-executor.4/429: #0: 00000000b398aa33 (event_mutex){+.+.}, at: perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 1 lock held by syz-executor.4/692: #0: 00000000b398aa33 (event_mutex){+.+.}, at: perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 3 locks held by kworker/0:3/651: 1 lock held by syz-executor.4/5407: #0: 00000000b398aa33 (event_mutex){+.+.}, at: perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 1 lock held by syz-executor.1/5509: #0: 00000000b398aa33 (event_mutex){+.+.}, at: perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1041 Comm: khungtaskd Not tainted 5.1.0-rc1 #28 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+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: