INFO: task syz-executor.4:4245 blocked for more than 143 seconds. Not tainted 5.2.0-rc7 #39 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28128 4245 9582 0x00004004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 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+0x10b/0x6c0 kernel/kthread.c:559 io_sq_thread_stop fs/io_uring.c:2252 [inline] io_finish_async+0x73/0x140 fs/io_uring.c:2259 io_ring_ctx_free fs/io_uring.c:2770 [inline] io_ring_ctx_wait_and_kill+0x133/0x600 fs/io_uring.c:2834 io_uring_release+0x42/0x50 fs/io_uring.c:2842 __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:185 [inline] exit_to_usermode_loop+0x273/0x2c0 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+0x58e/0x680 arch/x86/entry/common.c:304 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:00007fff7b4282b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00000000004134b1 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000004 RBP: 0000000000000000 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007fff7b428390 R11: 0000000000000293 R12: 000000000075bfc8 R13: 00000000000a0945 R14: 0000000000761120 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1043: #0: 000000006fb591f3 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5149 2 locks held by rsyslogd/9408: #0: 00000000c55663f3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: 000000006fb591f3 (rcu_read_lock){....}, at: __might_fault+0xfb/0x1e0 mm/memory.c:4495 2 locks held by getty/9530: #0: 000000002f16396b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000007e297caf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9531: #0: 00000000877dd237 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000c8cfdd57 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9532: #0: 000000000aa80fc0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000003493c8f5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9533: #0: 000000000ffc62a0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001fc31923 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9534: #0: 000000007412a418 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000006258683 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9535: #0: 00000000c2b3be0d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000164ee07b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9536: #0: 000000007c856edf (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008e5174ad (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1043 Comm: khungtaskd Not tainted 5.2.0-rc7 #39 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:205 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:289 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.2.0-rc7 #39 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:write_comp_data+0x68/0x70 kernel/kcov.c:147 Code: 00 00 4e 8d 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 0f 1f 80 00 00 00 00 55 40 0f b6 d6 40 0f b6 f7 31 ff 48 89 e5 RSP: 0018:ffff8880ae809cf0 EFLAGS: 00000006 RAX: 0000000000000102 RBX: ffff88805e9ca200 RCX: ffffffff8160aa0e RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff8880ae809cf8 R08: ffffffff88a7a100 R09: ffffffff88a7a9a0 R10: ffffffff88a7a980 R11: ffffffff88a7a100 R12: 0000000000000101 R13: ffff8880ae809da8 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000002394070 CR3: 000000008bcf2000 CR4: 00000000001406f0 Call Trace: trace_timer_expire_entry include/trace/events/timer.h:90 [inline] call_timer_fn+0x58e/0x720 kernel/time/timer.c:1321 expire_timers kernel/time/timer.c:1362 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x462/0x1740 kernel/time/timer.c:1698 __do_softirq+0x25c/0x94c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x180/0x1d0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x13b/0x550 arch/x86/kernel/apic/apic.c:1068 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806 RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61 Code: ff ff 48 89 df e8 92 2e 8c fa eb 82 e9 07 00 00 00 0f 00 2d 64 ad 4a 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 54 ad 4a 00 fb f4 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 7e 90 41 fa e8 39 RSP: 0018:ffffffff88a07cf8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1164e89 RBX: ffffffff88a7a100 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff88a7a97c RBP: ffffffff88a07d28 R08: ffffffff88a7a100 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff88b27438 R14: 0000000000000000 R15: 0000000000000000 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571 default_idle_call+0x36/0x90 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x377/0x560 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354 rest_init+0x245/0x37b init/main.c:451 arch_call_rest_init+0xe/0x1b start_kernel+0x854/0x893 init/main.c:761 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:472 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:453 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243