Buffer I/O error on dev loop0, logical block 0, lost async page write INFO: task blkid:6323 blocked for more than 120 seconds. Not tainted 4.4.119-g855ea74 #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D ffff8801c49af520 27560 6323 2295 0x00000004 ffff8801c49af520 ffff8801cdb7c780 ffff8801c49af4d8 ffffffff815c4071 ffff8801cdb7c780 dffffc0000000000 ffff8801db31fdb8 ffff8801db31fde0 ffff8801db31f4d8 ffff8801d9b49800 ffff8800ba7e9800 ffff8801c49afa50 Call Trace: [] schedule+0x7a/0x1b0 kernel/sched/core.c:3353 [] schedule_timeout+0x3a0/0x970 kernel/time/timer.c:1515 [] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:4935 [] io_schedule include/linux/sched.h:447 [inline] [] bit_wait_io+0x1b/0xc0 kernel/sched/wait.c:595 [] __wait_on_bit_lock+0x8f/0x140 kernel/sched/wait.c:434 [] __lock_page+0x18d/0x1f0 mm/filemap.c:888 [] lock_page include/linux/pagemap.h:458 [inline] [] write_cache_pages+0x73d/0xf70 mm/page-writeback.c:2217 [] generic_writepages+0xda/0x150 mm/page-writeback.c:2336 [] do_writepages+0xed/0x1c0 mm/page-writeback.c:2350 [] __filemap_fdatawrite_range+0x1b3/0x250 mm/filemap.c:347 [] __filemap_fdatawrite mm/filemap.c:355 [inline] [] filemap_fdatawrite mm/filemap.c:360 [inline] [] filemap_write_and_wait+0x61/0x120 mm/filemap.c:499 [] __sync_blockdev fs/block_dev.c:178 [inline] [] sync_blockdev.part.21+0x50/0x70 fs/block_dev.c:187 [] sync_blockdev fs/block_dev.c:174 [inline] [] __blkdev_put+0x184/0x7e0 fs/block_dev.c:1522 [] blkdev_put+0x85/0x550 fs/block_dev.c:1600 [] blkdev_close+0x8b/0xb0 fs/block_dev.c:1607 [] __fput+0x233/0x6d0 fs/file_table.c:208 [] ____fput+0x15/0x20 fs/file_table.c:244 [] task_work_run+0x104/0x180 kernel/task_work.c:115 [] tracehook_notify_resume include/linux/tracehook.h:191 [inline] [] exit_to_usermode_loop+0x13d/0x160 arch/x86/entry/common.c:252 [] prepare_exit_to_usermode arch/x86/entry/common.c:283 [inline] [] syscall_return_slowpath+0x1b5/0x1f0 arch/x86/entry/common.c:348 [] int_ret_from_sys_call+0x25/0xa3 1 lock held by blkid/6323: #0: (&bdev->bd_mutex){+.+.+.}, at: [] __blkdev_put+0xbc/0x7e0 fs/block_dev.c:1516 Sending NMI to all CPUs: NMI backtrace for cpu 0 CPU: 0 PID: 486 Comm: khungtaskd Not tainted 4.4.119-g855ea74 #28 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8800bac0b000 task.stack: ffff8800bac00000 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:ffff8800bac07cb8 EFLAGS: 00000046 RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000 RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300 RBP: ffff8800bac07ce0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000246 R13: 0000000000000003 R14: ffffffff8426f420 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f77ef9269b8 CR3: 00000001d1ac2000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff8426f420 ffffffff847efb00 fffffbfff08fda14 dffffc0000000000 ffff8801db31bca0 ffff8800bac07d00 ffffffff810b999b ffffffff839f63c0 0000000000000003 ffff8800bac07d60 ffffffff81d0ef94 ffffffff8141b013 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:506 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 6b 2f 17 00 4c 89 e7 57 9d 0f 1f NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.119-g855ea74 #28 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d9b49800 task.stack: ffff8801d9b58000 RIP: 0010:[] [] set_bit arch/x86/include/asm/bitops.h:75 [inline] RIP: 0010:[] [] set_ti_thread_flag include/linux/thread_info.h:42 [inline] RIP: 0010:[] [] __current_set_polling include/linux/sched.h:3231 [inline] RIP: 0010:[] [] cpuidle_idle_call kernel/sched/idle.c:192 [inline] RIP: 0010:[] [] cpu_idle_loop kernel/sched/idle.c:253 [inline] RIP: 0010:[] [] cpu_startup_entry+0x39f/0x8f0 kernel/sched/idle.c:301 RSP: 0018:ffff8801d9b5fe08 EFLAGS: 00000202 RAX: ffff8801d9b60000 RBX: dffffc0000000000 RCX: ffffffff81d63deb RDX: 0000000000000000 RSI: ffffffff839fe520 RDI: ffffffff839fe560 RBP: ffff8801d9b5fea8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff847ddc08 R13: fffffbfff070889c R14: ffffffff847ebf78 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd492cd5000 CR3: 00000001d1ac2000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: fffffbfff08fd7fe ffff8801d9b5fe30 0000000000000000 0000000041b58ab3 ffffffff83fa1c6b ffffffff81221570 ffffffff812ce9e2 43d9c20764c94cfb ffff8801db317fc0 ffffffff838445b0 0000000000000001 ffff8801db316040 Call Trace: [] start_secondary+0x304/0x3e0 arch/x86/kernel/smpboot.c:242 Code: 8b bd 70 ff ff ff 4c 89 fe 89 c2 e8 9c fb ff ff 4c 89 ff 89 c6 e8 b2 fe 93 01 65 48 8b 04 25 44 88 00 00 f0 80 88 0a 80 ff ff 20 <9c> 58 0f 1f 44 00 00 f6 c4 02 0f 85 ac fe ff ff 80 3d b4 8f 5b