INFO: task syz.0.221:5021 blocked for more than 144 seconds.
      Not tainted 5.15.166-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.221       state:D stack:    0 pid: 5021 ppid:  4573 flags:0x00000009
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6373
 schedule+0x11c/0x1c8 kernel/sched/core.c:6456
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x5b0/0x988 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x10c/0x398 kernel/locking/rwsem.c:1500
 iterate_supers+0xb0/0x1dc fs/super.c:714
 ksys_sync+0xb4/0x1cc fs/sync.c:102
 __arm64_sys_sync+0x14/0x24 fs/sync.c:113
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
3 locks held by kworker/1:1/25:
 #0: ffff0000d29f4938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001bd47c00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff800016be2128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72
1 lock held by khungtaskd/27:
 #0: ffff800014c817a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
2 locks held by kworker/0:2/1961:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff8000256d7c00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
2 locks held by getty/3788:
 #0: ffff0000d327a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001d52e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:3/4024:
3 locks held by kworker/0:5/4067:
 #0: ffff0000c0021938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800020277c00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0001b41a2918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:475 [inline]
 #2: ffff0001b41a2918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
 #2: ffff0001b41a2918 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1621 [inline]
 #2: ffff0001b41a2918 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x328/0x1e48 kernel/sched/core.c:6287
3 locks held by kworker/0:8/4070:
 #0: ffff0000d29f4938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff8000203a7c00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff800016be2128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72
1 lock held by syz-executor/4206:
 #0: ffff0000ce15c0e0 (&type->s_umount_key#61){++++}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
1 lock held by syz.0.221/5021:
 #0: ffff0000ce15c0e0 (&type->s_umount_key#61){++++}-{3:3}, at: iterate_supers+0xb0/0x1dc fs/super.c:714
2 locks held by kworker/u4:19/5107:
4 locks held by kworker/u4:22/5634:
 #0: ffff0000c03f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800020af7c00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff800016bd6950 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf4/0x9bc net/core/net_namespace.c:561
 #3: ffff800014c85da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #3: ffff800014c85da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x660 kernel/rcu/tree_exp.h:845
1 lock held by syz-executor/6600:
 #0: ffff800016be2128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffff800016be2128 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0xa2c/0xdac net/core/rtnetlink.c:5615
2 locks held by syz-executor/6671:
 #0: ffff800016be2128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffff800016be2128 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0xa2c/0xdac net/core/rtnetlink.c:5615
 #1: ffff800014c85da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #1: ffff800014c85da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2f0/0x660 kernel/rcu/tree_exp.h:845

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