INFO: task blkid:18536 blocked for more than 120 seconds. Not tainted 4.15.0+ #299 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D20416 18536 4143 0x80000006 Call Trace: context_switch kernel/sched/core.c:2845 [inline] __schedule+0x8eb/0x2060 kernel/sched/core.c:3421 schedule+0xf5/0x430 kernel/sched/core.c:3480 io_schedule+0x1c/0x70 kernel/sched/core.c:5096 wait_on_page_bit_common mm/filemap.c:1099 [inline] __lock_page+0x574/0x720 mm/filemap.c:1272 lock_page include/linux/pagemap.h:483 [inline] truncate_inode_pages_range+0x197c/0x1fe0 mm/truncate.c:448 truncate_inode_pages+0x24/0x30 mm/truncate.c:478 kill_bdev+0xbc/0xf0 fs/block_dev.c:86 __blkdev_put+0x198/0x7f0 fs/block_dev.c:1764 blkdev_put+0x85/0x4f0 fs/block_dev.c:1835 blkdev_close+0x8b/0xb0 fs/block_dev.c:1842 __fput+0x327/0x7e0 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x199/0x270 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x9bb/0x1ad0 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:968 get_signal+0x73a/0x16d0 kernel/signal.c:2469 do_signal+0x90/0x1e90 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x6ed/0x940 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x7f08a0af4310 RSP: 002b:00007ffecd68cb68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffffc RBX: 0000000000000000 RCX: 00007f08a0af4310 RDX: 0000000000000400 RSI: 0000000000fe5c58 RDI: 0000000000000003 RBP: 0000000000fe5c30 R08: 0000000000000028 R09: 0000000001680000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000fe5030 R13: 0000000000000400 R14: 0000000000fe5080 R15: 0000000000fe5c48 Showing all locks held in the system: 2 locks held by khungtaskd/759: #0: (rcu_read_lock){....}, at: [<00000000e510659a>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<00000000e510659a>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+}, at: [<00000000935622e3>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 2 locks held by getty/4132: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4133: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4134: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4135: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4136: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4137: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4138: #0: (&tty->ldisc_sem){++++}, at: [<00000000eeb8bb72>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000057b5cb6f>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 1 lock held by blkid/18536: #0: (&bdev->bd_mutex){+.+.}, at: [<000000005a779d07>] __blkdev_put+0xbc/0x7f0 fs/block_dev.c:1757 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 759 Comm: khungtaskd Not tainted 4.15.0+ #299 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:429 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+ #299 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lock_is_held_type+0x42/0x210 kernel/locking/lockdep.c:3951 RSP: 0018:ffff8801db407498 EFLAGS: 00000002 RAX: 0000000000000007 RBX: ffffffff86a2c340 RCX: 1ffff1003b6859fa RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff86a2cbb4 RBP: ffff8801db4074b8 R08: ffff88021fff801c R09: ffff88021fff8008 R10: ffff88021fff8010 R11: ffff88021fff801d R12: dffffc0000000000 R13: ffff8801db42c5d8 R14: ffff8801db4077f0 R15: 1ffff1003b680f14 FS: 0000000000000000(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001403000 CR3: 0000000006a22004 CR4: 00000000001606f0 DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: lock_is_held include/linux/lockdep.h:344 [inline] rq_clock_task kernel/sched/sched.h:928 [inline] cfs_rq_clock_task kernel/sched/fair.c:5103 [inline] update_blocked_averages+0xd28/0x1b60 kernel/sched/fair.c:7368 rebalance_domains+0x145/0xcc0 kernel/sched/fair.c:9123 run_rebalance_domains+0x378/0x770 kernel/sched/fair.c:9384 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 scheduler_ipi+0x318/0x820 kernel/sched/core.c:1804 smp_reschedule_interrupt+0xe6/0x670 arch/x86/kernel/smp.c:277 reschedule_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:849 RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54 RSP: 0018:ffffffff86a07c38 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 1ffffffff0d40f8a RCX: 0000000000000000 RDX: 1ffffffff0d59278 RSI: 0000000000000001 RDI: ffffffff86ac93c0 RBP: ffffffff86a07c38 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff86a07cf0 R14: ffffffff87269de0 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:93 [inline] default_idle+0xbf/0x430 arch/x86/kernel/process.c:354 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:345 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: 48 8b 1c 25 c0 ed 01 00 48 8d bb 74 08 00 00 48 83 ec 08 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 6e 01 00 00 8b 83 74 08 00 00 85 c0 0f 85 46 01 00