INFO: task syz.0.511:9364 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.511       state:D stack:27992 pid:9364  tgid:9361  ppid:5862   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 bdev_open+0xe0/0xd30
 blkdev_open+0x3a8/0x510
 do_dentry_open+0x953/0x13f0
 vfs_open+0x3b/0x340
 path_openat+0x2ee5/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8324f8d550
RSP: 002b:00007f8325dbfb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8324f8d550
RDX: 0000000000000000 RSI: 00007f8325dbfc10 RDI: 00000000ffffff9c
RBP: 00007f8325dbfc10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f83251c6218 R14: 00007f83251c6180 R15: 00007ffdbb4ed818
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5683:
 #0: ffff88810d1f70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
7 locks held by kworker/1:3/5918:
 #0: ffff88801bb35948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90004617bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: 
ffff888109ec6198 (&dev->mutex
){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff88810a1f3198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #4: ffff8881228e5160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #5: ffff88803613c9b8 (&go->hw_lock){+.+.}-{4:4}, at: go7007_boot_encoder+0x25/0xe0
 #6: ffffffff8dfe0310 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xf0/0x2b0
4 locks held by udevd/5929:
 #0: ffff8880321e12f0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff88810e096088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x55/0x3c0
 #2: ffff88811f0ab2d8 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0x75/0x3c0
 #3: ffff88810a1f3198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
1 lock held by udevd/5930:
 #0: ffff8881081df358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.0.511/9364:
 #0: ffff8881081df358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.8.844/11745:
 #0: ffff8881081df358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.9.862/11935:
 #0: ffffffff8e13f978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
1 lock held by udevadm/11977:

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

NMI backtrace for cpu 1
CPU: 1 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5730 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:mark_lock+0x3c/0x190
Code: 00 03 00 83 f9 01 bb 09 00 00 00 83 db 00 83 fa 08 0f 45 da bd 01 00 00 00 89 d9 d3 e5 25 ff 1f 00 00 48 0f a3 05 c4 88 0a 12 <73> 10 48 69 c0 c8 00 00 00 48 8d 88 10 13 49 93 eb 48 83 3d 2b 18
RSP: 0018:ffffc90002f8f8b8 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 0000000000000009 RCX: 0000000000000009
RDX: 0000000000000008 RSI: ffff88810d736180 RDI: ffff88810d735640
RBP: 0000000000000200 R08: 0000000000000000 R09: ffffffff8b473752
R10: dffffc0000000000 R11: ffffffff8b473680 R12: 00000000ffffff05
R13: 0000000000000001 R14: ffff88810d736180 R15: ffff88810d7361a0
FS:  0000000000000000(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 0000000023838000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __lock_acquire+0x6a8/0xd20
 lock_acquire+0x120/0x360
 batadv_nc_worker+0xef/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>
