INFO: task blkid:8890 blocked for more than 120 seconds. Not tainted 4.9.80-gb30d2b5 #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D27120 8890 2363 0x00000006 ffff8801b504c800 0000000000000000 ffff8801c3519f80 ffff8801d9b73000 ffff8801db321b98 ffff8801b4c57340 ffffffff838a23db 0000000041b58ab3 ffffffff84193128 00ffffff8123be80 ffff8801db322468 ffff8801db322490 Call Trace: [<ffffffff838a397f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3550 [<ffffffff838afadc>] schedule_timeout+0x56c/0x10b0 kernel/time/timer.c:1768 [<ffffffff838a1b8e>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:5172 [<ffffffff838a4df9>] io_schedule include/linux/sched.h:460 [inline] [<ffffffff838a4df9>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582 [<ffffffff838a4662>] __wait_on_bit_lock+0xc2/0x1c0 kernel/sched/wait.c:421 [<ffffffff81432ddf>] __lock_page+0xff/0x160 mm/filemap.c:934 [<ffffffff8146c7ea>] lock_page include/linux/pagemap.h:454 [inline] [<ffffffff8146c7ea>] truncate_inode_pages_range+0xc1a/0x12c0 mm/truncate.c:373 [<ffffffff8146ceb4>] truncate_inode_pages+0x24/0x30 mm/truncate.c:401 [<ffffffff8162a43c>] kill_bdev+0xbc/0xf0 fs/block_dev.c:96 [<ffffffff8162dc41>] __blkdev_put+0x191/0x7e0 fs/block_dev.c:1586 [<ffffffff8162f065>] blkdev_put+0x85/0x550 fs/block_dev.c:1663 [<ffffffff8162f5bb>] blkdev_close+0x8b/0xb0 fs/block_dev.c:1670 [<ffffffff8157568c>] __fput+0x28c/0x6e0 fs/file_table.c:208 [<ffffffff81575b65>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff811957d5>] task_work_run+0x115/0x190 kernel/task_work.c:116 [<ffffffff8113c277>] exit_task_work include/linux/task_work.h:21 [inline] [<ffffffff8113c277>] do_exit+0x7e7/0x2a40 kernel/exit.c:833 [<ffffffff81142988>] do_group_exit+0x108/0x320 kernel/exit.c:937 [<ffffffff811657e4>] get_signal+0x4d4/0x14e0 kernel/signal.c:2317 [<ffffffff81052c87>] do_signal+0x87/0x1a00 arch/x86/kernel/signal.c:807 [<ffffffff81003a31>] exit_to_usermode_loop+0xe1/0x120 arch/x86/entry/common.c:156 [<ffffffff81006340>] prepare_exit_to_usermode arch/x86/entry/common.c:190 [inline] [<ffffffff81006340>] syscall_return_slowpath+0x1a0/0x1e0 arch/x86/entry/common.c:259 [<ffffffff838b352b>] entry_SYSCALL_64_fastpath+0xe6/0xe8 Showing all locks held in the system: 2 locks held by khungtaskd/514: #0: (rcu_read_lock){......}, at: [<ffffffff81372ed5>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline] #0: (rcu_read_lock){......}, at: [<ffffffff81372ed5>] watchdog+0x125/0xa70 kernel/hung_task.c:239 #1: (tasklist_lock){.+.+..}, at: [<ffffffff81237fe0>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336 2 locks held by getty/3784: #0: (&tty->ldisc_sem){++++++}, at: [<ffffffff838b1652>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82009fa4>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133 1 lock held by blkid/8890: #0: (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162db6c>] __blkdev_put+0xbc/0x7e0 fs/block_dev.c:1579 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 514 Comm: khungtaskd Not tainted 4.9.80-gb30d2b5 #28 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801d928fd00 ffffffff81d94b69 0000000000000000 0000000000000001 0000000000000001 0000000000000001 ffffffff810bac60 ffff8801d928fd38 ffffffff81d9fc8d 0000000000000001 0000000000000000 ffff8801b504cc18 Call Trace: [<ffffffff81d94b69>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffffff81d94b69>] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [<ffffffff81d9fc8d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99 [<ffffffff81d9fdc7>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60 [<ffffffff810bad54>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [<ffffffff813734a0>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [<ffffffff813734a0>] check_hung_task kernel/hung_task.c:125 [inline] [<ffffffff813734a0>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [<ffffffff813734a0>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239 [<ffffffff8119a73d>] kthread+0x26d/0x300 kernel/kthread.c:211 [<ffffffff838b37dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:477 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff838b20c6