INFO: task syz-executor0:24603 blocked for more than 120 seconds. Not tainted 4.16.0-rc4+ #259 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D20112 24603 23842 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:1928 call_read_iter include/linux/fs.h:1775 [inline] generic_file_splice_read+0x3f9/0x7b0 fs/splice.c:307 do_splice_to+0x10a/0x160 fs/splice.c:880 splice_direct_to_actor+0x242/0x820 fs/splice.c:952 do_splice_direct+0x29b/0x3c0 fs/splice.c:1061 do_sendfile+0x5c9/0xe80 fs/read_write.c:1413 C_SYSC_sendfile fs/read_write.c:1489 [inline] compat_SyS_sendfile+0xea/0x1a0 fs/read_write.c:1478 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: 0023:0xf7fc7c99 RSP: 002b:00000000f77c309c EFLAGS: 00000286 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 0000000000000014 RDX: 00000000200000c0 RSI: 0000000000004200 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: [<00000000024b3a09>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<00000000024b3a09>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+}, at: [<00000000c4119703>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 2 locks held by kworker/0:1H/1634: #0: ((wq_completion)"kblockd"){+.+.}, at: [<00000000e27ac947>] work_static include/linux/workqueue.h:198 [inline] #0: ((wq_completion)"kblockd"){+.+.}, at: [<00000000e27ac947>] set_work_data kernel/workqueue.c:619 [inline] #0: ((wq_completion)"kblockd"){+.+.}, at: [<00000000e27ac947>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ((wq_completion)"kblockd"){+.+.}, at: [<00000000e27ac947>] process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 #1: ((work_completion)(&q->timeout_work)#2){+.+.}, at: [<00000000f2a85b9a>] process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 1 lock held by rsyslogd/3991: #0: (&f->f_pos_lock){+.+.}, at: [<000000009de61a19>] __fdget_pos+0x12b/0x190 fs/file.c:765 2 locks held by getty/4114: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4115: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4116: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4117: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4118: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4119: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4120: #0: (&tty->ldisc_sem){++++}, at: [<000000003e6ba5ff>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000dfa49885>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 799 Comm: khungtaskd Not tainted 4.16.0-rc4+ #259 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+0x123/0x180 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 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54