INFO: task loop0:5815 blocked for more than 120 seconds. Not tainted 4.4.124-g49632c6 #62 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. loop0 D ffff8801c416ede0 26904 5815 2 0x00000000 ffff8801c416ede0 0000000000064820 ffff8801c4170000 ffffffff8377a3e9 ffff8801c416ef00 ffff8801db21fdb8 ffff8801db21fde0 ffff8801db21f4d8 ffff8801db21f4c0 ffff8801d38ac800 ffff8801c4170000 ffff8801c416f670 Call Trace: [] schedule+0x7a/0x1b0 kernel/sched/core.c:3359 [] schedule_timeout+0x3a0/0x970 kernel/time/timer.c:1515 [] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:4941 [] io_schedule include/linux/sched.h:447 [inline] [] bt_get+0x305/0x760 block/blk-mq-tag.c:301 [] __blk_mq_get_tag block/blk-mq-tag.c:325 [inline] [] blk_mq_get_tag+0x1eb/0x340 block/blk-mq-tag.c:353 [] __blk_mq_alloc_request+0x24/0xa50 block/blk-mq.c:215 [] blk_mq_map_request+0x8d1/0xde0 block/blk-mq.c:1190 [] blk_sq_make_request+0x1a0/0xfc0 block/blk-mq.c:1361 [] generic_make_request+0x311/0x990 block/blk-core.c:2081 [] submit_bio+0x17a/0x540 block/blk-core.c:2154 [] dio_bio_submit fs/direct-io.c:409 [inline] [] do_blockdev_direct_IO+0x6ba8/0x8810 fs/direct-io.c:1283 [] __blockdev_direct_IO+0xae/0xe0 fs/direct-io.c:1342 [] blkdev_direct_IO+0xb2/0xe0 fs/block_dev.c:167 [] generic_file_read_iter+0x360/0x1160 mm/filemap.c:1791 [] blkdev_read_iter+0x105/0x170 fs/block_dev.c:1679 [] lo_rw_aio drivers/block/loop.c:506 [inline] [] lo_rw_simple drivers/block/loop.c:520 [inline] [] do_req_filebacked drivers/block/loop.c:558 [inline] [] loop_handle_cmd drivers/block/loop.c:1698 [inline] [] loop_queue_work+0x1eac/0x31c0 drivers/block/loop.c:1710 [] kthread_worker_fn+0x27b/0x600 kernel/kthread.c:602 [] kthread+0x268/0x300 kernel/kthread.c:211 [] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:510 no locks held by loop0/5815. Sending NMI to all CPUs: NMI backtrace for cpu 0 CPU: 0 PID: 487 Comm: khungtaskd Not tainted 4.4.124-g49632c6 #62 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8800bb9a8000 task.stack: ffff8800bad00000 RIP: 0010:[] [] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline] RIP: 0010:[] [] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline] RIP: 0010:[] [] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline] RIP: 0010:[] [] flat_send_IPI_mask+0xf7/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69 RSP: 0018:ffff8800bad07cb8 EFLAGS: 00000046 RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000 RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300 RBP: ffff8800bad07ce0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000246 R13: 0000000000000003 R14: ffffffff8426f5a0 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd83c8ae000 CR3: 00000001ca34a000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff8426f5a0 ffffffff847f09c0 fffffbfff08fdbec dffffc0000000000 ffff8801db31bca0 ffff8800bad07d00 ffffffff810b9adb ffffffff839f6e40 0000000000000003 ffff8800bad07d60 ffffffff81d115a4 0000000000000000 Call Trace: [] nmi_raise_cpu_backtrace+0x5b/0x70 arch/x86/kernel/apic/hw_nmi.c:33 [] nmi_trigger_all_cpu_backtrace+0x4a4/0x550 lib/nmi_backtrace.c:85 [] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 [] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog+0x6fa/0xae0 kernel/hung_task.c:238 [] kthread+0x268/0x300 kernel/kthread.c:211 [] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:510 Code: b3 5f ff f6 c4 10 75 e1 44 89 e8 c1 e0 18 89 04 25 10 b3 5f ff 44 89 fa 09 da 80 cf 04 41 83 ff 02 0f 44 d3 89 14 25 00 b3 5f ff <41> f7 c4 00 02 00 00 74 1a e8 8b 31 17 00 4c 89 e7 57 9d 0f 1f NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.124-g49632c6 #62 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d9b49800 task.stack: ffff8801d9b58000 RIP: 0010:[] [] _raw_spin_unlock_irqrestore+0x0/0x70 RSP: 0018:ffff8801d9b5fbf8 EFLAGS: 00000046 RAX: 0000000000000096 RBX: ffff8800bada9930 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000096 RDI: ffffffff857d7748 RBP: ffff8801d9b5fcc8 R08: 1ffff100174bf0ce R09: ffffffff8511a5d0 R10: 0000000000000001 R11: 1ffff1003b36bf46 R12: 1ffff1003b36bf84 R13: 0000000000000003 R14: dffffc0000000000 R15: ffffffff857d7748 FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdc580d7000 CR3: 00000001ca34a000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff81d6867d 0000000000000025 0000000000000000 ffffffff842c6460 ffff8801db319c40 0000000041b58ab3 ffffffff83fd02a1 ffffffff81d68410 0000000000000092 ffff8801db319c70 dffffc0000000000 ffff8801d9b5fd08 Call Trace: [] debug_hrtimer_deactivate kernel/time/hrtimer.c:415 [inline] [] debug_deactivate kernel/time/hrtimer.c:461 [inline] [] remove_hrtimer kernel/time/hrtimer.c:951 [inline] [] hrtimer_try_to_cancel+0x189/0x660 kernel/time/hrtimer.c:1059 [] hrtimer_cancel+0x22/0x40 kernel/time/hrtimer.c:1079 [] tick_nohz_restart+0x1e/0x190 kernel/time/tick-sched.c:559 [] tick_nohz_restart_sched_tick kernel/time/tick-sched.c:726 [inline] [] tick_nohz_idle_exit+0x247/0x3d0 kernel/time/tick-sched.c:946 [] cpu_idle_loop kernel/sched/idle.c:267 [inline] [] cpu_startup_entry+0x2a5/0x8f0 kernel/sched/idle.c:301 [] start_secondary+0x304/0x3e0 arch/x86/kernel/smpboot.c:242 Code: ab fd fb 66 0f 1f 44 00 00 bf 01 00 00 00 e8 a8 bb a2 fd 65 8b 05 41 d9 89 7c 85 c0 74 03 5b 5d c3 e8 eb a2 88 fd 5b 5d c3 66 90 <55> 48 89 e5 41 54 49 89 fc 48 83 c7 18 48 8b 55 08 53 48 89 f3