INFO: task syz-executor.0:30436 can't die for more than 143 seconds. syz-executor.0 D28160 30436 9035 0x00004004 Call Trace: context_switch kernel/sched/core.c:3252 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3878 schedule+0xa8/0x270 kernel/sched/core.c:3942 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+0x131/0x720 kernel/kthread.c:559 io_sq_thread_stop fs/io_uring.c:2464 [inline] io_finish_async+0x73/0x140 fs/io_uring.c:2471 io_ring_ctx_free fs/io_uring.c:2982 [inline] io_ring_ctx_wait_and_kill+0x133/0x600 fs/io_uring.c:3046 io_uring_release+0x42/0x50 fs/io_uring.c:3054 __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: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+0x5a9/0x6a0 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4134b1 Code: cf 48 c1 e9 03 4c 8b 05 85 1c 3b 01 48 c1 ef 05 49 29 f8 49 8d 78 ff 48 83 e1 03 48 83 fa 10 0f 84 a7 04 00 00 44 0f b6 43 17 <41> f6 c0 40 0f 85 58 04 00 00 4c 8b 03 48 8b 44 24 68 49 39 c0 0f RSP: 002b:00007ffd0a6448c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00000000004134b1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000001 R08: 00000000591263c1 R09: 00000000591263c5 R10: 00007ffd0a6449a0 R11: 0000000000000293 R12: 000000000075bf20 R13: 000000000007e0d5 R14: 00000000007615f0 R15: ffffffffffffffff INFO: task syz-executor.0:30436 blocked for more than 143 seconds. Not tainted 5.2.0-rc7-next-20190703 #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28160 30436 9035 0x00004004 Call Trace: context_switch kernel/sched/core.c:3252 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3878 schedule+0xa8/0x270 kernel/sched/core.c:3942 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+0x131/0x720 kernel/kthread.c:559 io_sq_thread_stop fs/io_uring.c:2464 [inline] io_finish_async+0x73/0x140 fs/io_uring.c:2471 io_ring_ctx_free fs/io_uring.c:2982 [inline] io_ring_ctx_wait_and_kill+0x133/0x600 fs/io_uring.c:3046 io_uring_release+0x42/0x50 fs/io_uring.c:3054 __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: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+0x5a9/0x6a0 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4134b1 Code: cf 48 c1 e9 03 4c 8b 05 85 1c 3b 01 48 c1 ef 05 49 29 f8 49 8d 78 ff 48 83 e1 03 48 83 fa 10 0f 84 a7 04 00 00 44 0f b6 43 17 <41> f6 c0 40 0f 85 58 04 00 00 4c 8b 03 48 8b 44 24 68 49 39 c0 0f RSP: 002b:00007ffd0a6448c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00000000004134b1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000001 R08: 00000000591263c1 R09: 00000000591263c5 R10: 00007ffd0a6449a0 R11: 0000000000000293 R12: 000000000075bf20 R13: 000000000007e0d5 R14: 00000000007615f0 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1045: #0: 0000000050bc9206 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5257 2 locks held by rsyslogd/8907: #0: 00000000b4748329 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: 00000000d97bd395 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1207 [inline] #1: 00000000d97bd395 (&rq->lock){-.-.}, at: __schedule+0x1f5/0x1580 kernel/sched/core.c:3830 2 locks held by getty/8997: #0: 0000000068d1b617 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008d4e2770 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8998: #0: 0000000068627bb7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a9b6c488 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8999: #0: 00000000db991e9f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000966c14dd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9000: #0: 0000000041d7baf9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a9f89cee (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9001: #0: 000000009b8bb399 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009d1baab7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9002: #0: 00000000f4f69b7d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e45a7dc8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9003: #0: 00000000635009b2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001b041da8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1045 Comm: khungtaskd Not tainted 5.2.0-rc7-next-20190703 #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+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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9099 Comm: kworker/u4:5 Not tainted 5.2.0-rc7-next-20190703 #28 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x0/0x20 kernel/kcov.c:174 Code: 5d c3 0f 1f 84 00 00 00 00 00 55 48 89 f2 48 89 fe bf 06 00 00 00 48 89 e5 48 8b 4d 08 e8 18 ff ff ff 5d c3 66 0f 1f 44 00 00 <55> 40 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 48 89 e5 48 8b 4d 08 e8 RSP: 0018:ffff888064fc7cd8 EFLAGS: 00000246 RAX: ffff888064fb8480 RBX: ffff88809fc35e80 RCX: ffffffff871794d8 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888064fc7d30 R08: ffff888064fb8480 R09: fffffbfff14a4141 R10: ffff888064fb8d68 R11: ffff888064fb8480 R12: 0000000000000000 R13: 0000000000000225 R14: ffff8880922651e8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000007b8000 CR3: 000000009858e000 CR4: 00000000001506e0 Call Trace: 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