IPVS: Creating netns size=2536 id=56
INFO: task syz-executor5:30569 blocked for more than 120 seconds.
      Not tainted 4.9.93-gf6bec4e #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D29080 30569   3842 0x20020004
 ffff8801a5d08000 0000000000000000 ffff8801cd2dcfc0 ffff8801d9b73000
 ffff8801db321b98 ffff8801cfdd7a90 ffffffff838c4a7d 1ffff10039fbaf46
 ffffffff85317ef8 0000000041b58ab3 00ffffff841a45f8 ffff8801db322468
Call Trace:
 [<ffffffff838c607f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3556
 [<ffffffff838d2491>] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768
 [<ffffffff838c425a>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5178
 [<ffffffff838c79b3>] do_wait_for_common kernel/sched/completion.c:75 [inline]
 [<ffffffff838c79b3>] __wait_for_common kernel/sched/completion.c:93 [inline]
 [<ffffffff838c79b3>] wait_for_common_io kernel/sched/completion.c:107 [inline]
 [<ffffffff838c79b3>] wait_for_completion_io+0x203/0x2e0 kernel/sched/completion.c:155
 [<ffffffff81ce39bb>] submit_bio_wait+0x11b/0x180 block/bio.c:885
 [<ffffffff81d1620b>] blkdev_issue_flush+0x15b/0x220 block/blk-flush.c:518
 [<ffffffff8162c6a5>] blkdev_fsync+0x85/0xb0 fs/block_dev.c:378
 [<ffffffff81617cac>] vfs_fsync_range+0x10c/0x260 fs/sync.c:195
 [<ffffffff81617e72>] vfs_fsync fs/sync.c:209 [inline]
 [<ffffffff81617e72>] do_fsync+0x42/0xb0 fs/sync.c:219
 [<ffffffff816185f6>] SYSC_fsync fs/sync.c:228 [inline]
 [<ffffffff816185f6>] SyS_fsync+0x16/0x20 fs/sync.c:226
 [<ffffffff81006da7>] do_syscall_32_irqs_on arch/x86/entry/common.c:325 [inline]
 [<ffffffff81006da7>] do_fast_syscall_32+0x2f7/0x870 arch/x86/entry/common.c:387
 [<ffffffff838d7050>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

Showing all locks held in the system:
2 locks held by khungtaskd/515:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813643dc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813643dc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423b90>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3748:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838d3b22>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82007e22>] n_tty_read+0x202/0x16b0 drivers/tty/n_tty.c:2133

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 515 Comm: khungtaskd Not tainted 4.9.93-gf6bec4e #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8b7fd08 ffffffff81d9c299 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b7d90 ffff8801d8b7fd40
 ffffffff81da75d7 0000000000000000 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81d9c299>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d9c299>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81da75d7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81da756a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b7e94>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81364974>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81364974>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81364974>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81364974>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119ab4d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838d5b1c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff838d4586