buffer_io_error: 64 callbacks suppressed
Buffer I/O error on dev loop0, logical block 16, async page read
Buffer I/O error on dev loop0, logical block 16, async page read
Buffer I/O error on dev loop0, logical block 16, async page read
INFO: task syz-executor7:12938 blocked for more than 120 seconds.
      Not tainted 4.9.92-g7cd9561 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor7   D27160 12938   3868 0x00000004
 ffff8801cc253000 ffff8801cbf9e4c0 ffff8801cbf9ea00 ffff8801b5ec3000
 ffff8801db321b98 ffff88019e7e7280 ffffffff838c49cd 0000000041b58ab3
 ffffffff841a4570 ffffffff81233c60 00ffffff814635a0 ffff8801db322468
Call Trace:
 [<ffffffff838c5fcf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3556
 [<ffffffff838d23e1>] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768
 [<ffffffff838c41aa>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5178
 [<ffffffff838c7419>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff838c7419>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff838c6b63>] __wait_on_bit+0x93/0x120 kernel/sched/wait.c:383
 [<ffffffff81431fe0>] wait_on_page_bit+0x130/0x140 mm/filemap.c:802
 [<ffffffff814321b1>] wait_on_page_writeback include/linux/pagemap.h:526 [inline]
 [<ffffffff814321b1>] __filemap_fdatawait_range+0x1c1/0x290 mm/filemap.c:453
 [<ffffffff814322a5>] filemap_fdatawait_range+0x25/0x50 mm/filemap.c:483
 [<ffffffff8143afe5>] filemap_write_and_wait_range+0x85/0xb0 mm/filemap.c:584
 [<ffffffff8162c8a6>] blkdev_fsync+0x66/0xb0 fs/block_dev.c:369
 [<ffffffff81617ecc>] vfs_fsync_range+0x10c/0x260 fs/sync.c:195
 [<ffffffff81630fb9>] generic_write_sync include/linux/fs.h:2590 [inline]
 [<ffffffff81630fb9>] blkdev_write_iter+0x2a9/0x370 fs/block_dev.c:1720
 [<ffffffff8156e150>] vfs_iter_write+0x2e0/0x460 fs/read_write.c:390
 [<ffffffff81614efb>] iter_file_splice_write+0x5fb/0xb30 fs/splice.c:768
 [<ffffffff8160ff68>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff8160ff68>] direct_splice_actor+0x128/0x190 fs/splice.c:1037
 [<ffffffff816112b1>] splice_direct_to_actor+0x2c1/0x7e0 fs/splice.c:992
 [<ffffffff81611973>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff81573020>] do_sendfile+0x4f0/0xc60 fs/read_write.c:1393
 [<ffffffff815750a1>] SYSC_sendfile64 fs/read_write.c:1448 [inline]
 [<ffffffff815750a1>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1440
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff838d58d3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
3 locks held by kworker/u4:0/6:
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118ab5e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118ab5e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118ab5e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118ab5e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff8118ab98>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
 #2:  (&type->s_umount_key#29){++++..}, at: [<ffffffff8157a140>] trylock_super+0x20/0xf0 fs/super.c:393
2 locks held by khungtaskd/516:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813643ec>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813643ec>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423dc0>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3744:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838d3a72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82008052>] n_tty_read+0x202/0x16b0 drivers/tty/n_tty.c:2133

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