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Buffer I/O error on dev loop0, logical block 3, lost async page write
INFO: task syz-executor1:29877 blocked for more than 120 seconds.
      Not tainted 4.4.124-g851fb4d #60
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor1   D ffff8801d7bcf2c0 26568 29877  29711 0x00000004
 ffff8801d7bcf2c0 ffff8800bacc68e0 0000000000000025 ffff8800bacc6000
 ffffffff842bdb00 ffff8801db21fdb8 ffff8801db21fde0 ffff8801db21f4d8
 ffff8801db21f4c0 ffffffff84217840 ffff8800bacc6000 ffff8801d7bcf860
Call Trace:
 [<ffffffff8376b59a>] schedule+0x7a/0x1b0 kernel/sched/core.c:3359
 [<ffffffff837768b0>] schedule_timeout+0x3a0/0x970 kernel/time/timer.c:1515
 [<ffffffff8376942e>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:4941
 [<ffffffff8376c85b>] io_schedule include/linux/sched.h:447 [inline]
 [<ffffffff8376c85b>] bit_wait_io+0x1b/0xc0 kernel/sched/wait.c:595
 [<ffffffff8376bf9c>] __wait_on_bit+0x8c/0x140 kernel/sched/wait.c:395
 [<ffffffff8141db65>] wait_on_page_bit+0x1e5/0x210 mm/filemap.c:758
 [<ffffffff8141dd53>] wait_on_page_writeback include/linux/pagemap.h:530 [inline]
 [<ffffffff8141dd53>] __filemap_fdatawait_range+0x1c3/0x2e0 mm/filemap.c:410
 [<ffffffff8141de95>] filemap_fdatawait_range+0x25/0x50 mm/filemap.c:440
 [<ffffffff81424064>] filemap_write_and_wait_range+0x74/0xb0 mm/filemap.c:539
 [<ffffffff815d0b06>] blkdev_fsync+0x66/0xb0 fs/block_dev.c:355
 [<ffffffff815bdb8a>] vfs_fsync_range+0x10a/0x250 fs/sync.c:195
 [<ffffffff815d2228>] generic_write_sync include/linux/fs.h:2498 [inline]
 [<ffffffff815d2228>] blkdev_write_iter+0x398/0x490 fs/block_dev.c:1658
 [<ffffffff8151d4d7>] vfs_iter_write+0x1c7/0x2d0 fs/read_write.c:364
 [<ffffffff815b8eaa>] iter_file_splice_write+0x58a/0xae0 fs/splice.c:1024
 [<ffffffff815b5885>] do_splice_from fs/splice.c:1128 [inline]
 [<ffffffff815b5885>] direct_splice_actor+0x125/0x180 fs/splice.c:1294
 [<ffffffff815b6b92>] splice_direct_to_actor+0x2d2/0x830 fs/splice.c:1247
 [<ffffffff815b7297>] do_splice_direct+0x1a7/0x270 fs/splice.c:1337
 [<ffffffff8152160c>] do_sendfile+0x54c/0xd30 fs/read_write.c:1227
 [<ffffffff81523663>] SYSC_sendfile64 fs/read_write.c:1282 [inline]
 [<ffffffff81523663>] SyS_sendfile64+0xc3/0x150 fs/read_write.c:1274
 [<ffffffff837796e5>] entry_SYSCALL_64_fastpath+0x22/0x9e
no locks held by syz-executor1/29877.
Sending NMI to all CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 486 Comm: khungtaskd Not tainted 4.4.124-g851fb4d #60
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800bbb8e000 task.stack: ffff8800bacc8000
RIP: 0010:[<ffffffff810c3fa7>]  [<ffffffff810c3fa7>] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline]
RIP: 0010:[<ffffffff810c3fa7>]  [<ffffffff810c3fa7>] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline]
RIP: 0010:[<ffffffff810c3fa7>]  [<ffffffff810c3fa7>] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline]
RIP: 0010:[<ffffffff810c3fa7>]  [<ffffffff810c3fa7>] flat_send_IPI_mask+0xf7/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69
RSP: 0018:ffff8800baccfcb8  EFLAGS: 00000046
RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000
RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300
RBP: ffff8800baccfce0 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: 000000c421d09010 CR3: 00000000ae540000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8426f5a0 ffffffff847f09c0 fffffbfff08fdbec dffffc0000000000
 ffff8801db31bca0 ffff8800baccfd00 ffffffff810b9adb ffffffff839f6e40
 0000000000000003 ffff8800baccfd60 ffffffff81d115a4 0000000000000000
Call Trace:
 [<ffffffff810b9adb>] nmi_raise_cpu_backtrace+0x5b/0x70 arch/x86/kernel/apic/hw_nmi.c:33
 [<ffffffff81d115a4>] nmi_trigger_all_cpu_backtrace+0x4a4/0x550 lib/nmi_backtrace.c:85
 [<ffffffff810b9b74>] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 [<ffffffff8136944a>] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline]
 [<ffffffff8136944a>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8136944a>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8136944a>] watchdog+0x6fa/0xae0 kernel/hung_task.c:238
 [<ffffffff811909c8>] kthread+0x268/0x300 kernel/kthread.c:211
 [<ffffffff83779b15>] 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-g851fb4d #60
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d9b49800 task.stack: ffff8801d9b58000
RIP: 0010:[<ffffffff810ecd16>]  [<ffffffff810ecd16>] variable_test_bit arch/x86/include/asm/bitops.h:318 [inline]
RIP: 0010:[<ffffffff810ecd16>]  [<ffffffff810ecd16>] cpumask_test_cpu include/linux/cpumask.h:294 [inline]
RIP: 0010:[<ffffffff810ecd16>]  [<ffffffff810ecd16>] switch_mm_irqs_off+0x2a6/0xc30 arch/x86/mm/tlb.c:169
RSP: 0018:ffff8801d9b5fd00  EFLAGS: 00000047
RAX: 0000000000000001 RBX: ffff8801c689c000 RCX: ffffffff81d663fb
RDX: ffff8801c689c000 RSI: ffffffff839ff020 RDI: ffffffff839ff060
RBP: ffff8801d9b5fd40 R08: ffffffff83844600 R09: 0000000000000001
R10: dffffc0000000000 R11: 1ffff1003b36bf72 R12: ffff8801c689c000
R13: ffff8801c689c000 R14: ffff8801d9b49ca0 R15: ffffffff847ece38
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001190000 CR3: 00000000ae540000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801db31f4d8 ffff8801db31fde8 ffffffff847ece38 ffff8801db31f4c0
 ffff8801c689c000 ffff8801c689c000 ffff8801d9b49ca0 ffffffff847ece38
 ffff8801d9b5fdc8 ffffffff8376a1d8 0000008bfe9e7fc4 ffff8801d9b5fda0
Call Trace:
 [<ffffffff8376a1d8>] context_switch kernel/sched/core.c:2792 [inline]
 [<ffffffff8376a1d8>] __schedule+0xbd8/0x1da0 kernel/sched/core.c:3330
 [<ffffffff8376b59a>] schedule+0x7a/0x1b0 kernel/sched/core.c:3359
 [<ffffffff8376bd93>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3392
 [<ffffffff81221b90>] cpu_idle_loop kernel/sched/idle.c:279 [inline]
 [<ffffffff81221b90>] cpu_startup_entry+0x2c0/0x8f0 kernel/sched/idle.c:301
 [<ffffffff810adcf4>] start_secondary+0x304/0x3e0 arch/x86/kernel/smpboot.c:242
Code: e9 0a ff ff ff 65 c7 05 0d 1e f3 7e 01 00 00 00 65 48 8b 15 fd 1d f3 7e 49 39 d4 0f 85 5f 05 00 00 89 c0 48 0f a3 83 60 03 00 00 <19> d2 85 d2 0f 85 34 ff ff ff f0 48 0f ab 83 60 03 00 00 48 8d