INFO: task syz.7.198:5314 blocked for more than 430 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.198       state:D stack:0     pid:5314  tgid:5313  ppid:4891   task_flags:0x40044c flags:0x00000011
Call trace:
 __switch_to+0x584/0xb00 arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x200c/0x3428 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xac/0x27c kernel/sched/core.c:6960
 schedule_timeout+0x68/0x1ec kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x28c/0x440 kernel/sched/completion.c:100
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x44/0x5c kernel/sched/completion.c:153
 __synchronize_srcu+0x2a4/0x320 kernel/rcu/srcutree.c:1518
 synchronize_srcu+0x3d0/0x4f8 kernel/rcu/srcutree.c:-1
 mn_hlist_release mm/mmu_notifier.c:347 [inline]
 __mmu_notifier_release+0x424/0x614 mm/mmu_notifier.c:359
 mmu_notifier_release include/linux/mmu_notifier.h:402 [inline]
 exit_mmap+0xbc/0xb8c mm/mmap.c:1260
 __mmput+0x10c/0x528 kernel/fork.c:1173
 mmput+0x70/0xa8 kernel/fork.c:1196
 exit_mm+0x158/0x248 kernel/exit.c:581
 do_exit+0x790/0x2378 kernel/exit.c:959
 do_group_exit+0x1d4/0x2ac kernel/exit.c:1112
 get_signal+0x1440/0x154c kernel/signal.c:3034
 arch_do_signal_or_restart+0x23c/0x4bac arch/arm64/kernel/signal.c:1619
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x88/0x188 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 exit_to_user_mode_prepare_legacy include/linux/irq-entry-common.h:242 [inline]
 arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:81 [inline]
 el0_svc+0x17c/0x238 arch/arm64/kernel/entry-common.c:725
 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:
3 locks held by kworker/u4:0/12:
3 locks held by kworker/u4:1/21:
1 lock held by khungtaskd/27:
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: __ll_sc_atomic64_fetch_or arch/arm64/include/asm/atomic_ll_sc.h:-1 [inline]
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: arch_atomic64_fetch_or arch/arm64/include/asm/atomic.h:86 [inline]
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: raw_atomic64_fetch_or include/linux/atomic/atomic-arch-fallback.h:3816 [inline]
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: raw_atomic_long_fetch_or include/linux/atomic/atomic-long.h:1090 [inline]
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: arch_test_and_set_bit include/asm-generic/bitops/atomic.h:42 [inline]
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline]
 #0: ffff800087a86d08 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x0/0x44 kernel/sched/sched.h:3748
1 lock held by syslogd/3129:
2 locks held by getty/3199:
 #0: 74f000001242e8a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: 8aff80008c80b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x308/0x1234 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/3333:
3 locks held by kworker/u4:8/3391:
3 locks held by kworker/u4:9/3589:
2 locks held by kworker/u4:2/3899:
2 locks held by kworker/u4:12/4893:
 #0: 61f000000cc26948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x7c8/0x1a10 kernel/workqueue.c:3231
 #1: ffff8000a2507c88 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x854/0x1a10 kernel/workqueue.c:3231
2 locks held by syz.8.197/5306:
2 locks held by kworker/u4:7/5336:
 #0: 61f000000cc26948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x7c8/0x1a10 kernel/workqueue.c:3231
 #1: ffff8000a1bb7c88 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x854/0x1a10 kernel/workqueue.c:3231
3 locks held by kworker/u4:13/5429:
1 lock held by modprobe/5457:

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