INFO: task syz-executor.2:2091 blocked for more than 140 seconds.
      Not tainted 4.9.202+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D25528  2091      1 0x00000004
 0000000000000083 ffff8801d1ecaf80 ffff8801a213d800 ffff8801db71ffc0
 ffff8801c716df00 ffff8801db71ffd8 ffff8801a4c1f688 ffffffff8280a1de
 0000000041b58ab3 ffffffff82e2ad88 00ffffff812051e0 ffff8801db7208b0
Call Trace:
 [<0000000017bf371f>] schedule+0x92/0x1c0 kernel/sched/core.c:3546
 [<000000002a036943>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3579
 [<0000000029d84256>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<0000000029d84256>] mutex_lock_nested+0x38d/0x920 kernel/locking/mutex.c:621
 [<000000003931fa90>] lo_open+0x1d/0xb0 drivers/block/loop.c:1622
 [<000000001920ec1c>] __blkdev_get+0x268/0xeb0 fs/block_dev.c:1287
 [<00000000256c1182>] blkdev_get+0x2e8/0x920 fs/block_dev.c:1424
 [<00000000a1da669d>] blkdev_open+0x1aa/0x250 fs/block_dev.c:1579
 [<0000000077f68316>] do_dentry_open+0x422/0xd20 fs/open.c:791
 [<0000000028b39dc7>] vfs_open+0x105/0x230 fs/open.c:904
 [<000000003d278456>] do_last fs/namei.c:3457 [inline]
 [<000000003d278456>] path_openat+0xbf5/0x2f60 fs/namei.c:3581
 [<00000000464eaa8c>] do_filp_open+0x1a1/0x280 fs/namei.c:3615
 [<0000000024295473>] do_sys_open+0x2f0/0x610 fs/open.c:1097
 [<000000000825d9ae>] SYSC_open fs/open.c:1115 [inline]
 [<000000000825d9ae>] SyS_open+0x2d/0x40 fs/open.c:1110
 [<0000000062c48a94>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
 [<00000000fb225dc2>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<0000000093a20d65>] check_hung_uninterruptible_tasks kernel/hung_task.c:169 [inline]
 #0:  (rcu_read_lock){......}, at: [<0000000093a20d65>] watchdog+0x14b/0xaf0 kernel/hung_task.c:263
 #1:  (tasklist_lock){.+.+..}, at: [<00000000032cfe8f>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4339
1 lock held by rsyslogd/1894:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<0000000010b050c3>] __fdget_pos+0xa8/0xd0 fs/file.c:782
2 locks held by getty/2022:
 #0:  (&tty->ldisc_sem){++++++}, at: [<00000000b4425189>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<00000000ea2de884>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.2/2091:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<000000004e6a6ac7>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
 #1:  (loop_index_mutex){+.+.+.}, at: [<000000003931fa90>] lo_open+0x1d/0xb0 drivers/block/loop.c:1622
1 lock held by syz-executor.4/2096:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<000000004e6a6ac7>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
2 locks held by syz-executor.3/5879:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<000000004e6a6ac7>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
 #1:  (loop_index_mutex){+.+.+.}, at: [<000000003931fa90>] lo_open+0x1d/0xb0 drivers/block/loop.c:1622
2 locks held by syz-executor.1/6833:
 #0:  (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<000000004569fd87>] lo_ioctl+0x8e/0x1b10 drivers/block/loop.c:1404
 #1:  (&bdev->bd_mutex){+.+.+.}, at: [<00000000b293cb87>] blkdev_reread_part+0x1f/0x40 block/ioctl.c:189
2 locks held by syz-executor.5/6835:
 #0:  (loop_index_mutex){+.+.+.}, at: [<00000000317a4e5d>] loop_control_ioctl+0x7a/0x320 drivers/block/loop.c:1974
 #1:  (&lo->lo_ctl_mutex#2){+.+.+.}, at: [<00000000fc238bd0>] loop_control_ioctl+0x17f/0x320 drivers/block/loop.c:1988
2 locks held by blkid/6832:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<000000004e6a6ac7>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
 #1:  (loop_index_mutex){+.+.+.}, at: [<000000003931fa90>] lo_open+0x1d/0xb0 drivers/block/loop.c:1622
2 locks held by blkid/6839:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<000000004e6a6ac7>] __blkdev_get+0x10e/0xeb0 fs/block_dev.c:1273
 #1:  (loop_index_mutex){+.+.+.}, at: [<000000003931fa90>] lo_open+0x1d/0xb0 drivers/block/loop.c:1622

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.202+ #0
 ffff8801d98d7cc8 ffffffff81b55d2b 0000000000000000 0000000000000000
 0000000000000000 ffffffff8109a001 dffffc0000000000 ffff8801d98d7d00
 ffffffff81b60fcc 0000000000000000 0000000000000000 0000000000000000
Call Trace:
 [<00000000d6a6e0c0>] __dump_stack lib/dump_stack.c:15 [inline]
 [<00000000d6a6e0c0>] dump_stack+0xcb/0x130 lib/dump_stack.c:56
 [<00000000181424c0>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99
 [<00000000c00ca97d>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60
 [<00000000a793e9ac>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<000000009aee681d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<000000009aee681d>] check_hung_task kernel/hung_task.c:126 [inline]
 [<000000009aee681d>] check_hung_uninterruptible_tasks kernel/hung_task.c:183 [inline]
 [<000000009aee681d>] watchdog+0x670/0xaf0 kernel/hung_task.c:263
 [<00000000252e62d3>] kthread+0x278/0x310 kernel/kthread.c:211
 [<0000000070f7e0df>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:375
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff82819331