INFO: task syz-executor3:12346 blocked for more than 120 seconds. Not tainted 4.16.0-rc3+ #245 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D20768 12346 4208 0x20020004 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440 schedule+0xf5/0x430 kernel/sched/core.c:3499 io_schedule+0x1c/0x70 kernel/sched/core.c:5115 __blkdev_direct_IO_simple+0x7bd/0xf50 fs/block_dev.c:241 blkdev_direct_IO+0xccb/0x1060 fs/block_dev.c:428 generic_file_read_iter+0x4cc/0x28e0 mm/filemap.c:2343 blkdev_read_iter+0x105/0x170 fs/block_dev.c:1913 call_read_iter include/linux/fs.h:1775 [inline] new_sync_read fs/read_write.c:401 [inline] __vfs_read+0x6a7/0xa00 fs/read_write.c:413 vfs_read+0x11e/0x350 fs/read_write.c:447 SYSC_pread64 fs/read_write.c:611 [inline] SyS_pread64+0x15b/0x190 fs/read_write.c:598 sys32_pread+0x39/0x50 arch/x86/ia32/sys_ia32.c:180 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f1ec99 RSP: 002b:00000000f771a09c EFLAGS: 00000286 ORIG_RAX: 00000000000000b4 RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000020000000 RDX: 00000000dffd1661 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 2 locks held by khungtaskd/799: #0: (rcu_read_lock){....}, at: [<0000000065af513f>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<0000000065af513f>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+}, at: [<00000000bd285dae>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 1 lock held by rsyslogd/4002: #0: (&f->f_pos_lock){+.+.}, at: [<000000009d853884>] __fdget_pos+0x12b/0x190 fs/file.c:765 2 locks held by getty/4124: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4125: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4126: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4127: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4128: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4129: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4130: #0: (&tty->ldisc_sem){++++}, at: [<0000000099aa8066>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000092388730>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 799 Comm: khungtaskd Not tainted 4.16.0-rc3+ #245 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x122/0x180 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:138 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0x90c/0xd60 kernel/hung_task.c:249 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54