b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
INFO: task kworker/1:3:7865 blocked for more than 120 seconds.
      Not tainted 4.9.98-ga03d0bb #18
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:3     D28936  7865      2 0x00000000
Workqueue: events_power_efficient reg_check_chans_work
 ffff8801ccb79800 ffff8801c6b6da40 ffff8801c6b6da40 ffff8801cb43b000
 ffff8801db321b98 ffff8801ca687a18 ffffffff839e377d ffff8801ccb7a0c8
__find_get_block_slow() failed. block=1, b_blocknr=8
 ffffed003996f418 ffff8801ccb79800 00fffc0000000000 ffff8801db322468
b_state=0x00000029, b_size=512
Call Trace:
device loop0 blocksize: 4096
 [<ffffffff839e4d7f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839e5703>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3590
 [<ffffffff839e9b86>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff839e9b86>] mutex_lock_nested+0x326/0x870 kernel/locking/mutex.c:621
__find_get_block_slow() failed. block=1, b_blocknr=8
 [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
b_state=0x00000029, b_size=512
 [<ffffffff836ddda4>] reg_check_chans_work+0x74/0xd90 net/wireless/reg.c:1652
 [<ffffffff8118ae31>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
device loop0 blocksize: 4096
 [<ffffffff8118bc26>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119ad5d>] kthread+0x26d/0x300 kernel/kthread.c:211
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
 [<ffffffff839f481c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
device loop0 blocksize: 4096

Showing all locks held in the system:
3 locks held by kworker/1:0/18:
 #0:  ("%s"("ipv6_addrconf")
__find_get_block_slow() failed. block=1, b_blocknr=8
){.+.+..}, at: [<ffffffff8118ad3e>] work_static include/linux/workqueue.h:186 [inline]
){.+.+..}, at: [<ffffffff8118ad3e>] set_work_data kernel/workqueue.c:617 [inline]
){.+.+..}, at: [<ffffffff8118ad3e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
){.+.+..}, at: [<ffffffff8118ad3e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
b_state=0x00000029, b_size=512
 (device loop0 blocksize: 4096
(addr_chk_work).work){+.+...}, at: [<ffffffff8118ad78>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646ec>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646ec>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423ba0>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
__find_get_block_slow() failed. block=1, b_blocknr=8
1 lock held by rsyslogd/3677:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d565c>] __fdget_pos+0xac/0xd0 fs/file.c:781
b_state=0x00000029, b_size=512
2 locks held by getty/3773:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f2822>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (
device loop0 blocksize: 4096
&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211cbb2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2133
3 locks held by kworker/1:3/7865:
 #0:  ("events_power_efficient"){.+.+.+}, at: [<ffffffff8118ad3e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_power_efficient"){.+.+.+}, at: [<ffffffff8118ad3e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_power_efficient"){.+.+.+}, at: [<ffffffff8118ad3e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_power_efficient"){.+.+.+}, at: [<ffffffff8118ad3e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
b_state=0x00000029, b_size=512
 #1:  ((reg_check_chans).work){+.+...}, at: [<ffffffff8118ad78>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
 #2:  (
device loop0 blocksize: 4096
rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
__find_get_block_slow() failed. block=1, b_blocknr=8
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
1 lock held by syz-executor0/8951:
 #0:  (
b_state=0x00000029, b_size=512
rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
1 lock held by syz-executor4/8952:
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b635b>] rtnl_lock net/core/rtnetlink.c:70 [inline]
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b635b>] rtnetlink_rcv+0x1b/0x40 net/core/rtnetlink.c:4064
1 lock held by syz-executor7/8935:
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
1 lock held by syz-executor7/8956:
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
1 lock held by syz-executor1/8942:
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
1 lock held by syz-executor1/8955:
__find_get_block_slow() failed. block=1, b_blocknr=8
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
b_state=0x00000029, b_size=512
1 lock held by syz-executor1/8959:
device loop0 blocksize: 4096
 #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff830b1837>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
1 lock held by init/8964:
__find_get_block_slow() failed. block=1, b_blocknr=8
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open+0x46c/0xe20 drivers/tty/tty_io.c:2125
b_state=0x00000029, b_size=512
1 lock held by init/8965:
device loop0 blocksize: 4096
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open+0x46c/0xe20 drivers/tty/tty_io.c:2125
1 lock held by init/8966:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open+0x46c/0xe20 drivers/tty/tty_io.c:2125
1 lock held by init/8967:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open+0x46c/0xe20 drivers/tty/tty_io.c:2125
1 lock held by init/8968:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open+0x46c/0xe20 drivers/tty/tty_io.c:2125
1 lock held by init/8969:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff82116c5c>] tty_open+0x46c/0xe20 drivers/tty/tty_io.c:2125

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

NMI backtrace for cpu 0
__find_get_block_slow() failed. block=1, b_blocknr=8
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.98-ga03d0bb #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
b_state=0x00000029, b_size=512
 ffff8801d8bafd08
device loop0 blocksize: 4096
 ffffffff81eb0e89 0000000000000000 0000000000000000
 ffffffff81ebc187 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb0e89>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb0e89>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebc187>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebc11a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b7ea4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81364c84>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81364c84>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81364c84>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81364c84>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
__find_get_block_slow() failed. block=1, b_blocknr=8
 [<ffffffff8119ad5d>] kthread+0x26d/0x300 kernel/kthread.c:211
b_state=0x00000029, b_size=512
 [<ffffffff839f481c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
device loop0 blocksize: 4096
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8927 Comm: syz-executor0 Not tainted 4.9.98-ga03d0bb #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801cb43b000 task.stack: ffff8801cb600000
RIP: 0010:[<ffffffff8123251e>] 
c [<ffffffff8123251e>] hlock_class kernel/locking/lockdep.c:142 [inline]
RIP: 0010:[<ffffffff8123251e>] 
c [<ffffffff8123251e>] mark_lock+0x4e/0x1280 kernel/locking/lockdep.c:3039
RSP: 0018:ffff8801cb606e08  EFLAGS: 00000046
RAX: 000000000000054a RBX: ffff8801cb43b8c8 RCX: 0000000000000007
RDX: 1ffff1003968771d RSI: ffff8801cb43b8c8 RDI: ffff8801cb43b000
RBP: ffff8801cb606e50 R08: ffff8801cb43b8e8 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801cb43b8c8
R13: 0000000000000080 R14: 0000000000000007 R15: ffff8801cb43b000
FS:  00007fe1944d1700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000171fb10 CR3: 00000001cf09a000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801cb606f2f
c 1ffff100396c0dc5
c ffffffff83cce0f7
c ffffffff83cce0f8
c
 0000000000000000
c ffff8801cb43b8c8
c ffffed0039687718
c ffff8801cb43b000
c
 dffffc0000000000
c ffff8801cb606ea0
c ffffffff81233817
c ffff88021fffd048
c
Call Trace:
 [<ffffffff81233817>] mark_held_locks+0xc7/0x130 kernel/locking/lockdep.c:2660
 [<ffffffff81233c0b>] __trace_hardirqs_on_caller kernel/locking/lockdep.c:2689 [inline]
 [<ffffffff81233c0b>] trace_hardirqs_on_caller+0x38b/0x590 kernel/locking/lockdep.c:2736
 [<ffffffff8100301a>] trace_hardirqs_on_thunk+0x1a/0x1c
 [<ffffffff839f4fe9>] retint_kernel+0x2d/0x2d
 [<ffffffff8125db48>] vprintk+0x28/0x30 kernel/printk/printk.c:1913
 [<ffffffff8125db6d>] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1914
 [<ffffffff8142a975>] vprintk_func kernel/printk/internal.h:36 [inline]
 [<ffffffff8142a975>] printk+0xaf/0xd7 kernel/printk/printk.c:1975
 [<ffffffff81cb7490>] __find_get_block_slow.cold.57+0xcd/0xf0 fs/buffer.c:244
 [<ffffffff81621a3e>] __find_get_block+0x23e/0x4c0 fs/buffer.c:1360
 [<ffffffff81622849>] __getblk_slow fs/buffer.c:1101 [inline]
 [<ffffffff81622849>] __getblk_gfp+0x189/0x710 fs/buffer.c:1386
 [<ffffffff816261ed>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818b3f68>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818b3f68>] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100
 [<ffffffff818b6bf1>] fat_get_entry fs/fat/dir.c:128 [inline]
 [<ffffffff818b6bf1>] fat_get_short_entry+0x131/0x2a0 fs/fat/dir.c:876
 [<ffffffff818b714d>] fat_scan+0xfd/0x340 fs/fat/dir.c:961
 [<ffffffff818de759>] msdos_find+0xf9/0x2d0 fs/fat/namei_msdos.c:128
 [<ffffffff818df075>] msdos_lookup+0x135/0x250 fs/fat/namei_msdos.c:208
 [<ffffffff8159249e>] lookup_slow+0x23e/0x470 fs/namei.c:1668
 [<ffffffff8159ea26>] walk_component+0x716/0x1bb0 fs/namei.c:1784
 [<ffffffff815a0749>] link_path_walk+0x889/0x1200 fs/namei.c:2120
 [<ffffffff815a13b4>] path_lookupat.isra.41+0x1b4/0x410 fs/namei.c:2282
 [<ffffffff815a35b9>] do_o_path fs/namei.c:3493 [inline]
 [<ffffffff815a35b9>] path_openat+0x1fa9/0x3590 fs/namei.c:3522
 [<ffffffff815a8e67>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff8156b63d>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff8156b960>] SYSC_openat fs/open.c:1099 [inline]
 [<ffffffff8156b960>] SyS_openat+0x30/0x40 fs/open.c:1093
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f4653>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
c48 
cc1 
cea 
c03 
c41 
cbd 
c01 
c00 
c00 
c00 
c41 
c54 
c41 
cd3 
ce5 
c53 
c48 
c89 
cf3 
c48 
c83 
cec 
c20 
c0f 
cb6 
c04 
c02 
c84 
cc0 
c74 
c08 
c3c 
c01 
c0f 
c8e 
cb0 
c04 
c00 
c00 
c0f 
cb7 
c43 
c20 
c<66> 
ca9 
cff 
c1f 
c74 
c7b 
c48 
cba 
c00 
c00 
c00 
c00 
c00 
cfc 
cff 
cdf 
c4c 
c89 
cc1 
c48 
cc1 
c