INFO: task syz.4.734:7078 blocked for more than 143 seconds.
      Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.734       state:D stack:25272 pid: 7078 ppid:  5048 flags:0x00004206
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
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 iterate_supers+0xac/0x1e0 fs/super.c:714
 ksys_sync+0xb9/0x1c0 fs/sync.c:102
 __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: 0033:0x7f363645eef9
RSP: 002b:00007f36348d7038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f3636616f80 RCX: 00007f363645eef9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f36364d1b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3636616f80 R15: 00007ffdb88d5f48
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/3014:
 #0: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa8/0x140 kernel/sched/core.c:483
2 locks held by getty/3325:
 #0: ffff88814b3b8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc9000209b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/3566:
 #0: ffff88805ddd60e0 (&type->s_umount_key#89){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
2 locks held by kworker/u4:19/6416:
1 lock held by syz.4.734/7078:
 #0: ffff88805ddd60e0 (&type->s_umount_key#89){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:714
1 lock held by syz-executor/7202:
 #0: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #0: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
1 lock held by syz.1.1157/8930:

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6416 Comm: kworker/u4:19 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: bat_events batadv_tt_purge
RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:55 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x4a/0x290 mm/kasan/generic.c:189
Code: 48 c1 ed 2f 81 fd ff ff 01 00 0f 82 46 02 00 00 48 89 fb 48 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4e 8d 0c 03 4c 8d 54 37 ff <49> c1 ea 03 49 bb 01 00 00 00 00 fc ff df 4f 8d 34 1a 4c 89 f5 4c
RSP: 0018:ffffc90003577aa8 EFLAGS: 00000a06
RAX: 0000000000000001 RBX: 1ffff1100cadd730 RCX: ffffffff816427a4
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880656eb980
RBP: 000000000001ffff R08: dffffc0000000000 R09: ffffed100cadd730
R10: ffff8880656eb983 R11: dffffc0000000001 R12: ffff8880170cbd08
R13: 0000000000000000 R14: ffffffff8a148bb0 R15: ffff8880656eb980
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f88cc0d58 CR3: 0000000028045000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 queued_spin_is_locked include/asm-generic/qspinlock.h:28 [inline]
 debug_spin_unlock kernel/locking/spinlock_debug.c:100 [inline]
 do_raw_spin_unlock+0x54/0x8b0 kernel/locking/spinlock_debug.c:140
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:175 [inline]
 _raw_spin_unlock_bh+0x1f/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:408 [inline]
 batadv_tt_local_purge+0x2a0/0x340 net/batman-adv/translation-table.c:1356
 batadv_tt_purge+0x31/0xa40 net/batman-adv/translation-table.c:3560
 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>