INFO: task syz-executor.4:9964 blocked for more than 143 seconds. Not tainted 5.2.0-rc5+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28128 9964 8387 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: 0033:0x412fb1 Code: 75 52 0f b6 19 48 ff c1 0f ba e3 00 73 de 48 89 54 24 20 89 5c 24 1c 48 89 4c 24 38 48 8b 44 24 68 48 8d 0c 02 48 8b 5c 24 60 <48> 8d 34 1a 48 8b 09 48 89 4c 24 08 48 89 34 24 e8 9a ea ff ff 48 RSP: 002b:00007ffebd9eb960 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412fb1 RDX: 0000001b2fe20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: 000000001c5f1c3e R09: 000000001c5f1c42 R10: 00007ffebd9eba40 R11: 0000000000000293 R12: 00000000007604b0 R13: 000000000016ed4d R14: 000000000016ed7a R15: 000000000075bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1043: #0: 000000000cacd35d (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5149 1 lock held by rsyslogd/8246: #0: 00000000dfbd6ee4 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8336: #0: 00000000ad66d55c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008fe3f707 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8337: #0: 00000000fd776bdf (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006f8f8148 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8338: #0: 00000000cbc2776b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000044f2627e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8339: #0: 000000002fa323e0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000aa5b55ba (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8340: #0: 0000000025e46f1f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000cf98b598 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8341: #0: 00000000b627ebec (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000061f1b21f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8342: #0: 000000001ba3f69e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a30ed2cc (&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-rc5+ #38 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-rc5+ #38 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_release kernel/locking/lockdep.c:4053 [inline] RIP: 0010:lock_release+0x23c/0xa00 kernel/locking/lockdep.c:4322 Code: df 4c 89 f2 48 c1 ea 03 0f b6 14 02 4c 89 f0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 f8 05 00 00 44 89 c8 0b 05 a4 3a 0e 09 <0f> 84 b9 03 00 00 44 89 ca 4c 89 c7 4c 89 e6 44 89 8d 60 ff ff ff RSP: 0018:ffffffff88a07b40 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 1ffffffff1140f6e RCX: 1ffffffff130187e RDX: 0000000000000004 RSI: 1ffffffff10ea04c RDI: 0000000000000001 RBP: ffffffff88a07bf8 R08: ffffffff88a7a100 R09: 0000000000000001 R10: ffffffff88a7a980 R11: ffffffff88a7a100 R12: ffff8880ae8354d8 R13: ffffffff814d85f6 R14: ffffffff8a65ad40 R15: ffffffff88a07bd0 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001cda220 CR3: 00000000a038d000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:166 [inline] _raw_spin_unlock_irq+0x1b/0x90 kernel/locking/spinlock.c:199 finish_lock_switch kernel/sched/core.c:2568 [inline] finish_task_switch+0x146/0x730 kernel/sched/core.c:2668 context_switch kernel/sched/core.c:2821 [inline] __schedule+0x7d3/0x1560 kernel/sched/core.c:3445 schedule_idle+0x58/0x80 kernel/sched/core.c:3537 do_idle+0x192/0x560 kernel/sched/idle.c:287 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:470 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:451 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243