INFO: task syz.5.329:8013 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.329       state:D stack:0     pid:8013  tgid:8011  ppid:7338   task_flags:0x400040 flags:0x00000011
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7017
 rwsem_down_read_slowpath+0x578/0x86c kernel/locking/rwsem.c:1086
 __down_read_common kernel/locking/rwsem.c:1261 [inline]
 __down_read kernel/locking/rwsem.c:1274 [inline]
 down_read+0x9c/0x308 kernel/locking/rwsem.c:1539
 __super_lock fs/super.c:59 [inline]
 super_lock+0x240/0x32c fs/super.c:121
 __iterate_supers+0x130/0x5bc fs/super.c:923
 iterate_supers+0x2c/0x3c fs/super.c:939
 ksys_sync+0x90/0x164 fs/sync.c:102
 __arm64_sys_sync+0x14/0x24 fs/sync.c:113
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
1 lock held by khungtaskd/32:
 #0: ffff80008fa5b6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
1 lock held by pr/ttyAMA-1/43:
2 locks held by kworker/u8:18/5399:
4 locks held by kworker/u8:19/6020:
 #0: ffff0000c1843148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009f9f7be0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff800092ad79d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf0/0x638 net/core/net_namespace.c:670
 #3: ffff80008fa610c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x58/0x528 kernel/rcu/tree.c:3816
2 locks held by getty/6353:
 #0: ffff0000c19ce0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800099f1e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfc8 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/6572:
1 lock held by syz.5.329/8013:
 #0: ffff0000d2c9c0e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
 #0: ffff0000d2c9c0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x240/0x32c fs/super.c:121
3 locks held by syz.1.1907/13430:
1 lock held by syz.4.1910/13441:

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