INFO: task loop0:14081 blocked for more than 120 seconds.
Not tainted 4.15.0-rc9+ #280
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
loop0 D24976 14081 2 0x80000000
Call Trace:
context_switch kernel/sched/core.c:2799 [inline]
__schedule+0x8eb/0x2060 kernel/sched/core.c:3375
schedule+0xf5/0x430 kernel/sched/core.c:3434
schedule_timeout+0x1a3/0x230 kernel/time/timer.c:1769
io_schedule_timeout+0x26/0x80 kernel/sched/core.c:5030
do_wait_for_common kernel/sched/completion.c:86 [inline]
__wait_for_common kernel/sched/completion.c:107 [inline]
wait_for_common_io kernel/sched/completion.c:124 [inline]
wait_for_completion_io+0x415/0x770 kernel/sched/completion.c:172
submit_bio_wait+0x13f/0x1e0 block/bio.c:947
blkdev_issue_flush+0x226/0x310 block/blk-flush.c:548
blkdev_fsync+0x86/0xb0 fs/block_dev.c:632
vfs_fsync_range+0x110/0x260 fs/sync.c:196
vfs_fsync+0x29/0x30 fs/sync.c:210
lo_req_flush drivers/block/loop.c:444 [inline]
do_req_filebacked drivers/block/loop.c:572 [inline]
loop_handle_cmd drivers/block/loop.c:1724 [inline]
loop_queue_work+0x12a2/0x3900 drivers/block/loop.c:1738
kthread_worker_fn+0x32b/0x980 kernel/kthread.c:642
loop_kthread_worker_fn+0x51/0x60 drivers/block/loop.c:841
kthread+0x33c/0x400 kernel/kthread.c:238
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:541
Showing all locks held in the system:
2 locks held by khungtaskd/746:
#0: (rcu_read_lock){....}, at: [<000000005ba154aa>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
#0: (rcu_read_lock){....}, at: [<000000005ba154aa>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249
#1: (tasklist_lock){.+.+}, at: [<00000000a0666adb>] debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4464
1 lock held by rsyslogd/3503:
#0: (&f->f_pos_lock){+.+.}, at: [<00000000c0e2cb9b>] __fdget_pos+0x12b/0x190 fs/file.c:770
2 locks held by getty/3626:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3627:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3628:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3629:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3630:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3631:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/521:
#0: (&tty->ldisc_sem){++++}, at: [<00000000129dd02a>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000021b0d542>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 746 Comm: khungtaskd Not tainted 4.15.0-rc9+ #280
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+0x194/0x257 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:541
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc9+ #280
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rcu_read_lock_sched_held+0x8/0x120 kernel/rcu/update.c:107
RSP: 0018:ffff8801db207b58 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff86809138 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff870386e0 RDI: ffffffff870387c4
RBP: ffff8801db207d48 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000040
R13: 0000000000000007 R14: ffffffff86809100 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f87a7256db8 CR3: 0000000006822002 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
invoke_softirq kernel/softirq.c:365 [inline]
irq_exit+0x1cc/0x200 kernel/softirq.c:405
scheduler_ipi+0x318/0x820 kernel/sched/core.c:1803
smp_reschedule_interrupt+0xe6/0x670 arch/x86/kernel/smp.c:277
reschedule_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:961
</IRQ>
RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54
RSP: 0018:ffffffff86807c38 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff02
RAX: dffffc0000000000 RBX: 1ffffffff0d00f8a RCX: 0000000000000000
RDX: 1ffffffff0d19190 RSI: 0000000000000001 RDI: ffffffff868c8c80
RBP: ffffffff86807c38 R08: ffffffff86670ae0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff86807cf0 R14: ffffffff870386e0 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:93 [inline]
default_idle+0xbf/0x460 arch/x86/kernel/process.c:355
arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:346
default_idle_call+0x36/0x90 kernel/sched/idle.c:98
cpuidle_idle_call kernel/sched/idle.c:156 [inline]
do_idle+0x24a/0x3b0 kernel/sched/idle.c:246
cpu_startup_entry+0x104/0x120 kernel/sched/idle.c:351
rest_init+0xed/0xf0 init/main.c:436
start_kernel+0x7f1/0x819 init/main.c:716
x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378
x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237
Code: 58 0f 1f 44 00 00 48 c1 e8 09 48 83 f0 01 83 e0 01 5d c3 0f 0b e8 99 bb 4a 00 eb d9 0f 1f 80 00 00 00 00 48 c7 c7 c4 87 03 87 55 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 48 89 e5 53