RDX: 000000000000001b RSI: 0000000000000029 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000020 R09: 0000000000000000 R10: 0000000020000100 R11: 0000000000000246 R12: 00007f8dfaaf36d4 R13: 00000000004cef20 R14: 00000000004dda40 R15: 0000000000000005 INFO: task kworker/u4:7:24559 blocked for more than 140 seconds. Not tainted 4.19.67 #41 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:7 D24920 24559 2 0x80000000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 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/0x14b0 kernel/workqueue.c:2707 rxrpc_destroy_all_connections+0x103/0x487 net/rxrpc/conn_object.c:471 rxrpc_exit_net+0x1c2/0x310 net/rxrpc/net_ns.c:123 ops_exit_list.isra.0+0xaa/0x150 net/core/net_namespace.c:153 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552 process_one_work+0x989/0x1750 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task syz-executor.1:30588 blocked for more than 140 seconds. Not tainted 4.19.67 #41 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28216 30588 15616 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780 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+0x12e/0x210 kernel/rcu/srcutree.c:936 synchronize_srcu_expedited kernel/rcu/srcutree.c:961 [inline] synchronize_srcu+0x239/0x3e8 kernel/rcu/srcutree.c:1012 tracepoint_synchronize_unregister include/linux/tracepoint.h:84 [inline] perf_trace_event_unreg.isra.0+0xc6/0x220 kernel/trace/trace_event_perf.c:163 perf_trace_destroy+0xbc/0x100 kernel/trace/trace_event_perf.c:238 tp_perf_event_destroy+0x16/0x20 kernel/events/core.c:8402 _free_event+0x354/0x1220 kernel/events/core.c:4453 put_event+0x47/0x60 kernel/events/core.c:4547 perf_event_release_kernel+0x6d1/0xd80 kernel/events/core.c:4662 perf_release+0x37/0x50 kernel/events/core.c:4672 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413511 Code: 8c d6 65 00 ba 02 00 00 00 bf 28 38 44 00 ff 15 7d a1 24 00 85 c0 0f 85 37 fe ff ff 31 c9 31 f6 41 b9 b0 20 41 00 41 b8 90 d6 <65> 00 ba 03 00 00 00 bf 31 38 44 00 ff 15 55 a1 24 00 85 c0 0f 85 RSP: 002b:00007ffc03468b20 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413511 RDX: 0000001b33b20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000f1ed4f10 R09: 00000000f1ed4f14 R10: 00007ffc03468c00 R11: 0000000000000293 R12: 000000000075bf20 R13: 00000000002396a7 R14: 0000000000761fd0 R15: ffffffffffffffff Showing all locks held in the system: 2 locks held by kworker/u4:2/45: 1 lock held by khungtaskd/1037: #0: 0000000037957466 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4435 1 lock held by udevd/3601: 1 lock held by rsyslogd/7126: #0: 00000000657f1675 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/7249: #0: 0000000061c9226b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000002d54a45 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7250: #0: 000000001ea80625 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c9c2e98c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7251: #0: 00000000f4cab7a0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a6d97f22 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7252: #0: 00000000d281faa0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000006f89097c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7253: #0: 0000000078dbe844 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c4bdd20f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7254: #0: 00000000d3f75164 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000055c7085c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7255: #0: 00000000eb7c7945 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c1bcef55 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 3 locks held by kworker/u4:7/24559: #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000bdf0ab31 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124 #1: 000000005d9233e1 (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 #2: 0000000075e70e32 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:519 3 locks held by kworker/1:1/24322: 1 lock held by syz-executor.1/30588: #0: 00000000c578af34 (event_mutex){+.+.}, at: perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:236 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1037 Comm: khungtaskd Not tainted 4.19.67 #41 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+0x1b0/0x1f8 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:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 45 Comm: kworker/u4:2 Not tainted 4.19.67 #41 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_release kernel/locking/lockdep.c:3678 [inline] RIP: 0010:lock_release+0x2e6/0xa30 kernel/locking/lockdep.c:3919 Code: 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 0c 11 48 89 fa 83 e2 07 83 c2 01 38 ca 7c 08 84 c9 0f 85 e3 05 00 00 66 f7 40 22 f0 ff <74> 37 48 8d 78 20 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 RSP: 0018:ffff8880a988fb80 EFLAGS: 00000046 RAX: ffff8880a987cd50 RBX: 1ffff11015311f76 RCX: 0000000000000000 RDX: 0000000000000003 RSI: ffff8880a9110f30 RDI: ffff8880a987cd72 RBP: ffff8880a988fc38 R08: ffff8880a987c480 R09: 0000000000000003 R10: ffffed10152221e3 R11: ffff8880a9110f1b R12: ffff8880a9110f30 R13: ffffffff86d86c75 R14: ffffffff8a37f660 R15: ffff8880a988fc10 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000961b3000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:174 [inline] _raw_spin_unlock_bh+0x1b/0x40 kernel/locking/spinlock.c:200 spin_unlock_bh include/linux/spinlock.h:374 [inline] batadv_nc_purge_paths+0x265/0x370 net/batman-adv/network-coding.c:482 batadv_nc_worker+0x29c/0x760 net/batman-adv/network-coding.c:731 process_one_work+0x989/0x1750 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415