INFO: task syz.0.471:9047 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.471       state:D stack:25128 pid:9047  tgid:9046  ppid:8413   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f441dd8eba9
RSP: 002b:00007f441ec57038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f441dfd5fa0 RCX: 00007f441dd8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f441dfd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f441dfd6038 R14: 00007f441dfd5fa0 R15: 00007ffe18192608
 </TASK>
INFO: task syz.0.471:9050 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.471       state:D stack:28936 pid:9050  tgid:9046  ppid:8413   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f441dd8eba9
RSP: 002b:00007f441ec36038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f441dfd6090 RCX: 00007f441dd8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f441dfd6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f441dfd6128 R14: 00007f441dfd6090 R15: 00007ffe18192608
 </TASK>
INFO: task syz.0.471:9051 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.471       state:D stack:28936 pid:9051  tgid:9046  ppid:8413   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f441dd8eba9
RSP: 002b:00007f441ec15038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f441dfd6180 RCX: 00007f441dd8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f441dfd6180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f441dfd6218 R14: 00007f441dfd6180 R15: 00007ffe18192608
 </TASK>
INFO: task syz.0.471:9052 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.471       state:D stack:25896 pid:9052  tgid:9046  ppid:8413   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f441dd8eba9
RSP: 002b:00007f441ebf4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f441dfd6270 RCX: 00007f441dd8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f441dfd6270 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f441dfd6308 R14: 00007f441dfd6270 R15: 00007ffe18192608
 </TASK>
INFO: task syz.0.471:9053 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.471       state:D stack:28936 pid:9053  tgid:9046  ppid:8413   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f441dd8eba9
RSP: 002b:00007f441ebd3038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f441dfd6360 RCX: 00007f441dd8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f441dfd6360 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f441dfd63f8 R14: 00007f441dfd6360 R15: 00007ffe18192608
 </TASK>
INFO: task syz.0.471:9054 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.471       state:D stack:28936 pid:9054  tgid:9046  ppid:8413   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f441dd8eba9
RSP: 002b:00007f441ebb2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f441dfd6450 RCX: 00007f441dd8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f441dfd6450 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f441dfd64e8 R14: 00007f441dfd6450 R15: 00007ffe18192608
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
7 locks held by kworker/0:2/793:
 #0: ffff888104b41148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000449fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88810b042198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff888041f40198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x950
 #4: ffff888021d70160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800
 #5: ffffffff8efa7f48 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x328/0x640
 #6: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
1 lock held by syslogd/5280:
 #0: ffff888136639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
2 locks held by getty/5674:
 #0: ffff8880277b70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
4 locks held by udevd/5848:
 #0: ffff88803e565c30 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff888031928488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x55/0x3c0
 #2: ffff88803c9ed5a8 (kn->active#32){.+.+}-{0:0}, at: kernfs_seq_start+0x75/0x3c0
 #3: ffff888041f40198 (&dev->mutex){....}-{4:4}, at: product_show+0x26/0xa0
4 locks held by syz-executor/5852:
4 locks held by udevd/5941:
 #0: ffff88810bebac30 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff888128eff088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x55/0x3c0
 #2: ffff888035b25698 (kn->active#31){++++}-{0:0}, at: kernfs_seq_start+0x75/0x3c0
 #3: ffff8880219fa198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
6 locks held by kworker/0:6/6046:
 #0: ffff888104b41148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900062a7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88802194a198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff8880219fa198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #4: ffff88802efcc160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #5: ffffffff8dfe0350 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xf0/0x2b0
1 lock held by syz.0.471/9047:
 #0: ffff8881254c80e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.471/9050:
 #0: ffff8881254c80e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.471/9051:
 #0: ffff8881254c80e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.471/9052:
 #0: ffff8881254c80e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.471/9053:
 #0: ffff8881254c80e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.471/9054:
 #0: ffff8881254c80e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.3.858/11036:
 #0: ffff88802194a198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5744 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: bat_events batadv_nc_worker
RIP: 0010:check_preemption_disabled+0x6/0x120
Code: c7 c6 60 39 e3 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 <48> 83 ec 10 65 48 8b 05 be 6e 26 07 48 89 44 24 08 65 8b 05 c6 6e
RSP: 0018:ffffc900030678e8 EFLAGS: 00000046
RAX: ffff888020398000 RBX: 0000000000000000 RCX: 2e4e6bbd4caa7100
RDX: 0000000000000000 RSI: ffffffff8d9cce41 RDI: ffffffff8be33980
RBP: ffffffff8b481d2a R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47407 R12: 0000000000000002
R13: ffffffff8e139f20 R14: 0000000000000000 R15: 0000000000000246
FS:  0000000000000000(0000) GS:ffff8881a3c15000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560e7ad1f7e8 CR3: 0000000035efa000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0xe7/0x360
 batadv_nc_process_nc_paths+0xdb/0x3a0
 batadv_nc_worker+0x429/0x610
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
