INFO: task syz.8.247:6414 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.247       state:D stack:0     pid:6414  tgid:6409  ppid:5943   task_flags:0x400040 flags:0x00800011
Call trace:
 __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:792 (T)
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x1368/0x2b50 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7474
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x5d8/0x10b8 kernel/locking/mutex.c:821
 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874
 sync_bdevs+0x220/0x3f0 block/bdev.c:1378
 ksys_sync+0xc4/0x118 fs/sync.c:105
 __arm64_sys_sync+0x14/0x24 fs/sync.c:111
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:797
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:816
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606

Showing all locks held in the system:
locks held by kworker/u8:1/13: 4, last CPU#1:
 #0: ffff0000c004c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3470 [inline]
 #0: ffff0000c004c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x8c8/0x1250 kernel/workqueue.c:3578
 #1: ffff80008fa57c20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3470 [inline]
 #1: ffff80008fa57c20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x8d0/0x1250 kernel/workqueue.c:3578
 #2: ffff0001acea0d58 (&base->lock){-.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
 #2: ffff0001acea0d58 (&base->lock){-.-.}-{2:2}, at: neigh_periodic_work+0x8c/0x9fc net/core/neighbour.c:984
 #3: ffff0001acea1e18 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0xe8/0x1b0 kernel/time/timer.c:1005
locks held by khungtaskd/31: 1, last CPU#0:
 #0: ffff800089aa56a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff800089aa56a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff800089aa56a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6871
locks held by getty/4492: 2, on CPU#1:
 #0: ffff0000ca00c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000932db2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x350/0xffc drivers/tty/n_tty.c:2211
locks held by udevd/4705: 1, on CPU#1:
 #0: ffff0000c7c7e350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xc4/0x880 block/bdev.c:990
locks held by syz.8.247/6414: 1, on CPU#0:
 #0: ffff0000c7c7e350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x220/0x3f0 block/bdev.c:1378

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