INFO: task syz.0.1833:11852 blocked for more than 143 seconds.
      Not tainted 5.15.169-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1833      state:D stack:25280 pid:11852 ppid:  4167 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 exfat_sync_fs+0x67/0x100 fs/exfat/super.c:64
 iterate_supers+0x127/0x1e0 fs/super.c:718
 ksys_sync+0xd7/0x1c0 fs/sync.c:104
 __do_sys_sync+0xa/0x10 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f62d626a719
RSP: 002b:00007f62d46e2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f62d6421f80 RCX: 00007f62d626a719
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f62d62dd32e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f62d6421f80 R15: 00007ffd30b185f8
 </TASK>

Showing all locks held in the system:
1 lock held by ksoftirqd/0/14:
 #0: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3934:
 #0: ffff88802cd52098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025ae2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
2 locks held by udevd/5207:
 #0: ffff888020fa9d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
 #1: ffff88814738f468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa9/0xbe0 drivers/block/loop.c:1365
3 locks held by syz-executor/8432:
2 locks held by syz.0.1833/11852:
 #0: ffff8880605520e0 (&type->s_umount_key#79){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:716
 #1: ffff8880605540e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_sync_fs+0x67/0x100 fs/exfat/super.c:64

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.169-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9 Comm: kworker/u4:0 Not tainted 5.15.169-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205
Code: 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 08 f4 68 0c 48 89 de 5b e9 c7 f2 48 00 cc cc cc cc cc cc cc 48 8b 04 24 <65> 48 8b 0d d4 fb 81 7e 65 8b 15 d5 fb 81 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc90000ce7a50 EFLAGS: 00000283
RAX: ffffffff8a0be885 RBX: 000000000000036d RCX: 1ffff1100384e130
RDX: 0000000000000000 RSI: 000000000000036d RDI: ffffffff8ad90480
RBP: ffffc90000ce7b98 R08: dffffc0000000000 R09: fffffbfff1bd2cb6
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888064601800
R13: ffff88801c270980 R14: ffff888024449b68 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e74f442950 CR3: 000000002b60a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline]
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline]
 batadv_iv_ogm_schedule+0x429/0x1000 net/batman-adv/bat_iv_ogm.c:869
 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>