INFO: task syz.7.208:5066 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.7.208       state:D stack:0     pid:5066  tgid:5064  ppid:4830   task_flags:0x40044c flags:0x00000018
Call trace:
 __switch_to+0x584/0xb20 arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1eec/0x33a4 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xac/0x27c kernel/sched/core.c:7058
 schedule_timeout+0x5c/0x1e4 kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x28c/0x444 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:1444
 synchronize_srcu+0x3cc/0x4f0 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+0xb8/0xbb8 mm/mmap.c:1263
 __mmput+0x10c/0x528 kernel/fork.c:1130
 mmput+0x70/0xac kernel/fork.c:1152
 exit_mm+0x158/0x258 kernel/exit.c:582
 do_exit+0x788/0x2378 kernel/exit.c:949
 do_group_exit+0x1d4/0x2ac kernel/exit.c:1102
 get_signal+0x1440/0x1554 kernel/signal.c:3034
 do_signal+0x23c/0x4dd0 arch/arm64/kernel/signal.c:1618
 do_notify_resume+0xb0/0x270 arch/arm64/kernel/entry-common.c:152
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline]
 el0_svc+0xb8/0x164 arch/arm64/kernel/entry-common.c:880
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
3 locks held by kworker/u4:1/21:
1 lock held by khungtaskd/27:
 #0: ffff800087876d18 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
2 locks held by getty/3187:
 #0: 96f0000011d0e8a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: c1ff80008c5cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x310/0x12b8 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/3308:
3 locks held by kworker/u4:6/3421:
2 locks held by kworker/u4:0/3652:
 #0: 3bf000000cc20948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7c8/0x1a18 kernel/workqueue.c:3210
 #1: ffff80008cda7c78 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x854/0x1a18 kernel/workqueue.c:3210
2 locks held by kworker/u4:3/3654:
3 locks held by kworker/u4:8/3788:
2 locks held by kworker/u4:4/4167:
3 locks held by kworker/u4:7/4170:
3 locks held by kworker/u4:10/4184:
3 locks held by kworker/u4:5/4532:
3 locks held by kworker/u4:11/4725:
2 locks held by syz.6.218/5040:
3 locks held by kworker/u4:14/5166:
2 locks held by dhcpcd-run-hook/5253:
2 locks held by modprobe/5255:
2 locks held by kworker/u4:3/5256:
1 lock held by dhcpcd-run-hook/5257:

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