INFO: task syz-executor.3:9570 can't die for more than 143 seconds. syz-executor.3 D28136 9570 8651 0x00004004 Call Trace: context_switch kernel/sched/core.c:2842 [inline] __schedule+0x755/0x15b0 kernel/sched/core.c:3468 schedule+0xa8/0x270 kernel/sched/core.c:3532 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1783 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 kthread_stop+0x131/0x730 kernel/kthread.c:559 io_sq_thread_stop fs/io_uring.c:2249 [inline] io_finish_async+0x73/0x140 fs/io_uring.c:2256 io_ring_ctx_free fs/io_uring.c:2767 [inline] io_ring_ctx_wait_and_kill+0x133/0x600 fs/io_uring.c:2831 io_uring_release+0x42/0x50 fs/io_uring.c:2839 __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+0x280/0x2d0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413201 Code: 48 89 54 24 10 48 85 d2 0f 86 cd 00 00 00 48 89 d3 31 d2 48 f7 f3 48 c7 41 30 00 00 00 00 48 c7 41 40 ff ff ff ff 48 89 41 38 <48> c7 41 48 00 00 00 00 48 c7 41 50 00 00 00 00 48 8b 41 38 48 89 RSP: 002b:00007fff61a67730 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000413201 RDX: 0000000000000000 RSI: 0000000000000081 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000760ea0 R09: ffffffffffffffff R10: 00007fff61a67800 R11: 0000000000000293 R12: 0000000000760ea8 R13: 0000000000000004 R14: 0000000000000000 R15: ffffffffffffffff INFO: task syz-executor.3:9570 blocked for more than 143 seconds. Not tainted 5.2.0-rc6-next-20190624 #21 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28136 9570 8651 0x00004004 Call Trace: context_switch kernel/sched/core.c:2842 [inline] __schedule+0x755/0x15b0 kernel/sched/core.c:3468 schedule+0xa8/0x270 kernel/sched/core.c:3532 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1783 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 kthread_stop+0x131/0x730 kernel/kthread.c:559 io_sq_thread_stop fs/io_uring.c:2249 [inline] io_finish_async+0x73/0x140 fs/io_uring.c:2256 io_ring_ctx_free fs/io_uring.c:2767 [inline] io_ring_ctx_wait_and_kill+0x133/0x600 fs/io_uring.c:2831 io_uring_release+0x42/0x50 fs/io_uring.c:2839 __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+0x280/0x2d0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413201 Code: 48 89 54 24 10 48 85 d2 0f 86 cd 00 00 00 48 89 d3 31 d2 48 f7 f3 48 c7 41 30 00 00 00 00 48 c7 41 40 ff ff ff ff 48 89 41 38 <48> c7 41 48 00 00 00 00 48 c7 41 50 00 00 00 00 48 8b 41 38 48 89 RSP: 002b:00007fff61a67730 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000413201 RDX: 0000000000000000 RSI: 0000000000000081 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000760ea0 R09: ffffffffffffffff R10: 00007fff61a67800 R11: 0000000000000293 R12: 0000000000760ea8 R13: 0000000000000004 R14: 0000000000000000 R15: ffffffffffffffff Showing all locks held in the system: 3 locks held by kworker/u4:1/21: #0: 00000000c161776e (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9755 [inline] #0: 00000000c161776e (&rq->lock){-.-.}, at: pick_next_task_fair+0x1227/0x19b0 kernel/sched/fair.c:6796 #1: 000000003c828251 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:5792 #2: 00000000d442157d (&base->lock){-.-.}, at: lock_timer_base+0x56/0x1b0 kernel/time/timer.c:932 1 lock held by khungtaskd/1045: #0: 000000003c828251 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5262 1 lock held by rsyslogd/8513: #0: 00000000a5b99471 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8603: #0: 000000000b031915 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000003c79e653 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8604: #0: 000000004efdb525 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000004eed5679 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8605: #0: 00000000378aa922 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000356c4b4f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8606: #0: 00000000e6ce80c4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000075b93abf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8607: #0: 000000006346f10a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001823e977 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8608: #0: 000000000cce817f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009a8e8db5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8609: #0: 000000000a93e55e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000004f9cfe84 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1045 Comm: khungtaskd Not tainted 5.2.0-rc6-next-20190624 #21 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:249 [inline] watchdog+0xc54/0x1320 kernel/hung_task.c:333 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:353 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.2.0-rc6-next-20190624 #21 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:match_held_lock+0xb/0x510 kernel/locking/lockdep.c:3943 Code: ec ff 48 c7 c7 c0 b3 d2 88 89 45 84 e8 2e e0 53 00 8b 45 84 e9 67 ff ff ff 66 0f 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 89 fb 48 83 c7 10 48 89 fa RSP: 0018:ffff8880a9a37bb0 EFLAGS: 00000086 RAX: dffffc0000000000 RBX: 0000000000000003 RCX: ffff8880a9a37c68 RDX: 0000000000000003 RSI: ffffffff88da73c0 RDI: ffff8880a9a26e60 RBP: ffff8880a9a37bf0 R08: 0000000000000003 R09: ffff8880a9a26e08 R10: fffffbfff13431df R11: ffffffff89a18eff R12: ffff8880a9a26e60 R13: ffffffff8712289a R14: ffffffff88da73c0 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000091119000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_release kernel/locking/lockdep.c:4172 [inline] lock_release+0x254/0x960 kernel/locking/lockdep.c:4437 rcu_lock_release include/linux/rcupdate.h:213 [inline] rcu_read_unlock include/linux/rcupdate.h:647 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline] batadv_nc_worker+0x225/0x760 net/batman-adv/network-coding.c:718 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:353