INFO: task syz-executor.4:5056 blocked for more than 143 seconds.
      Not tainted 6.4.0-syzkaller-11479-g6cd06ab12d1a #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:23672 pid:5056  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xc9a/0x5880 kernel/sched/core.c:6710
 schedule+0xde/0x1a0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 rwsem_down_write_slowpath+0x3e2/0x1220 kernel/locking/rwsem.c:1178
 __down_write_common kernel/locking/rwsem.c:1306 [inline]
 __down_write kernel/locking/rwsem.c:1315 [inline]
 down_write+0x1d2/0x200 kernel/locking/rwsem.c:1574
 deactivate_super+0xa9/0xd0 fs/super.c:360
 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1254
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f9a1108d7f7
RSP: 002b:00007fffa9629e48 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f9a1108d7f7
RDX: 00007fffa9629f1c RSI: 000000000000000a RDI: 00007fffa9629f10
RBP: 00007fffa9629f10 R08: 00000000ffffffff R09: 00007fffa9629ce0
R10: 0000555556434893 R11: 0000000000000246 R12: 00007f9a110d643b
R13: 00007fffa962afd0 R14: 0000555556434810 R15: 00007fffa962b010
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/13:
 #0: ffffffff8c9a3af0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:522
1 lock held by rcu_tasks_trace/14:
 #0: ffffffff8c9a37f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:522
1 lock held by khungtaskd/28:
 #0: ffffffff8c9a4700 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6615
2 locks held by getty/4767:
 #0: ffff88802cab2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xf08/0x13f0 drivers/tty/n_tty.c:2187
1 lock held by syz-executor.4/5056:
 #0: ffff88802eaf40e0 (&type->s_umount_key#103){++++}-{3:3}, at: deactivate_super+0xa9/0xd0 fs/super.c:360
5 locks held by syz-executor.3/12797:
1 lock held by syz-executor.3/12839:
 #0: ffff88802eaf40e0 (&type->s_umount_key#103){++++}-{3:3}, at: iterate_supers+0xdf/0x2a0 fs/super.c:742

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.4.0-syzkaller-11479-g6cd06ab12d1a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xe16/0x1090 kernel/hung_task.c:379
 kthread+0x344/0x440 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7341 Comm: kworker/u4:8 Not tainted 6.4.0-syzkaller-11479-g6cd06ab12d1a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: bat_events batadv_nc_worker
RIP: 0010:rcu_is_watching+0x0/0xb0 kernel/rcu/tree.c:691
Code: 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 c7 c7 20 02 6e 8a e8 40 2c b1 08 65 8a 05 75 f6 95 7e 0f b6 c0 c3 0f 1f 44 00 00 <f3> 0f 1e fa 55 53 65 ff 05 bb db 95 7e e8 fe 2b b1 08 48 c7 c3 e8
RSP: 0018:ffffc9000478fc88 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff888019b01698 RCX: 0000000000000000
RDX: ffff888021660000 RSI: ffffffff89e9d32c RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff888078e1d6d8
R13: 0000000000000000 R14: dffffc0000000000 R15: 00000000000002d3
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557a1a06e600 CR3: 0000000019b6d000 CR4: 0000000000350ee0
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 rcu_read_lock include/linux/rcupdate.h:750 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xbc1/0xfe0 net/batman-adv/network-coding.c:719
 process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2748
 kthread+0x344/0x440 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>