INFO: task syz.0.16:5177 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.16        state:D stack:27272 pid: 5177 ppid:  5060 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit kernel/sched/wait_bit.c:49 [inline]
 out_of_line_wait_on_bit+0x15e/0x200 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 __wait_on_buffer fs/buffer.c:122 [inline]
 wait_on_buffer include/linux/buffer_head.h:390 [inline]
 __bread_slow fs/buffer.c:1181 [inline]
 __bread_gfp+0x2c2/0x380 fs/buffer.c:1384
 sb_bread include/linux/buffer_head.h:337 [inline]
 qnx6_check_first_superblock+0xa1/0x320 fs/qnx6/inode.c:265
 qnx6_fill_super+0x341/0x1990 fs/qnx6/inode.c:335
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f36769f0d29
RSP: 002b:00007f3675c69038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3676be0fa0 RCX: 00007f36769f0d29
RDX: 0000000020000580 RSI: 0000000020000480 RDI: 0000000020000440
RBP: 00007f3676a6cb08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000010000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3676be0fa0 R15: 00007ffda3acd338
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3951:
 #0: ffff88802bfeb098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz.0.16/5177:
 #0: ffff88807b84c0e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.1.17/5215:
 #0: ffff88807d9ee0e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.2.18/5237:
 #0: ffff88805c3de0e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.3.19/5260:
 #0: ffff8880758e60e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.4.20/5294:
 #0: ffff88805c6080e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.5.21/5322:
 #0: ffff8880581b40e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.6.22/5350:
 #0: ffff88805644c0e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.7.23/5382:
 #0: ffff88807ea140e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.8.24/5411:
 #0: ffff8880562d80e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
1 lock held by syz.9.25/5439:
 #0: ffff888055b540e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 9 Comm: kworker/u4:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:hlock_class kernel/locking/lockdep.c:197 [inline]
RIP: 0010:mark_lock+0x9c/0x320 kernel/locking/lockdep.c:4569
Code: 89 c7 41 81 e7 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 c0 e0 fb 8f be 08 00 00 00 e8 9c 84 5f 00 4c 0f a3 3d 94 2f 9f 0e <73> 10 4b 8d 04 7f c1 e0 06 4c 8d b8 80 5f 94 8f eb 24 48 c7 c0 80
RSP: 0018:ffffc90000ce7980 EFLAGS: 00000057
RAX: 0000000000000101 RBX: ffff88813fed0000 RCX: ffffffff815cb124
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbe1c8
RBP: 0000000000000002 R08: dffffc0000000000 R09: fffffbfff1ff7c3a
R10: fffffbfff1ff7c3a R11: 1ffffffff1ff7c39 R12: 0000000000000004
R13: dffffc0000000000 R14: ffff88813fed0af0 R15: 000000000000084a
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c6aa3bfa38 CR3: 000000002a87c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mark_held_locks kernel/locking/lockdep.c:4193 [inline]
 __trace_hardirqs_on_caller kernel/locking/lockdep.c:4211 [inline]
 lockdep_hardirqs_on_prepare+0x23c/0x760 kernel/locking/lockdep.c:4278
 trace_hardirqs_on+0x67/0x80 kernel/trace/trace_preemptirq.c:49
 __local_bh_enable_ip+0x12a/0x1b0 kernel/softirq.c:406
 spin_unlock_bh include/linux/spinlock.h:409 [inline]
 batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475
 batadv_nc_worker+0x327/0x5c0 net/batman-adv/network-coding.c:726
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>