INFO: task syz.8.403:6082 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.8.403       state:D stack:0     pid:6082  tgid:6080  ppid:5658   task_flags:0x40044c flags:0x00000010
Call trace:
 __switch_to+0x5e0/0xb5c arch/arm64/kernel/process.c:810 (T)
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1f54/0x38a8 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0xac/0x27c kernel/sched/core.c:7283
 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+0x1b4/0x1f4 kernel/rcu/srcutree.c:1496
 synchronize_srcu+0x668/0x8dc kernel/rcu/srcutree.c:-1
 mn_hlist_release mm/mmu_notifier.c:373 [inline]
 __mmu_notifier_release+0x668/0x858 mm/mmu_notifier.c:385
 mmu_notifier_release include/linux/mmu_notifier.h:443 [inline]
 exit_mmap+0xcc/0xb64 mm/mmap.c:1282
 __mmput+0x10c/0x528 kernel/fork.c:1178
 mmput+0x70/0xa8 kernel/fork.c:1201
 exit_mm+0x1e4/0x2f8 kernel/exit.c:582
 do_exit+0x828/0x2404 kernel/exit.c:964
 do_group_exit+0x1d4/0x2ac kernel/exit.c:1119
 get_signal+0x1440/0x154c kernel/signal.c:3037
 arch_do_signal_or_restart+0x23c/0x4bf4 arch/arm64/kernel/signal.c:1665
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x88/0x188 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x184/0x238 arch/arm64/kernel/entry-common.c:741
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:759
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Showing all locks held in the system:
1 lock held by khungtaskd/26:
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: __ll_sc_atomic64_fetch_or arch/arm64/include/asm/atomic_ll_sc.h:-1 [inline]
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: arch_atomic64_fetch_or arch/arm64/include/asm/atomic.h:86 [inline]
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: raw_atomic64_fetch_or include/linux/atomic/atomic-arch-fallback.h:3816 [inline]
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: raw_atomic_long_fetch_or include/linux/atomic/atomic-long.h:1090 [inline]
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: arch_test_and_set_bit include/asm-generic/bitops/atomic.h:42 [inline]
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline]
 #0: ffff800087dc48b8 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x0/0x44 kernel/sched/sched.h:3869
3 locks held by kworker/u4:3/41:
2 locks held by getty/3234:
 #0: 5bf00000127a60a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: 39ff80008cb5b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x310/0x1284 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/3363:
3 locks held by kworker/u4:2/4011:
3 locks held by kworker/u4:6/4787:
2 locks held by kworker/u4:7/4976:
3 locks held by kworker/u4:9/5362:
2 locks held by kworker/u4:11/5414:
 #0: 21f000000d036540 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x7f8/0x1d80 kernel/workqueue.c:3288
 #1: ffff80008f6b7ca8 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x884/0x1d80 kernel/workqueue.c:3288
3 locks held by kworker/u4:14/5824:
2 locks held by syz.7.401/6069:
2 locks held by kworker/u4:1/6125:
 #0: 21f000000d036540 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x7f8/0x1d80 kernel/workqueue.c:3288
 #1: ffff80008f9c7ca8 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x884/0x1d80 kernel/workqueue.c:3288
3 locks held by kworker/u4:5/6142:
4 locks held by cmp/6254:
2 locks held by modprobe/6255:
1 lock held by modprobe/6256:

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