INFO: task syz.2.931:9550 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.931       state:D stack:0     pid:9550  tgid:9549  ppid:4711   task_flags:0x400140 flags:0x00000011
Call trace:
 __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7362
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7419
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x4ec/0xf14 kernel/locking/mutex.c:821
 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874
 sync_bdevs+0x214/0x3d4 block/bdev.c:1369
 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+0x64/0x260 arch/arm64/kernel/entry-common.c:758
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590
INFO: task syz.2.931:9552 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.931       state:D stack:0     pid:9552  tgid:9549  ppid:4711   task_flags:0x400140 flags:0x00000011
Call trace:
 __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7362
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7419
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x4ec/0xf14 kernel/locking/mutex.c:821
 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874
 sync_bdevs+0x214/0x3d4 block/bdev.c:1369
 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+0x64/0x260 arch/arm64/kernel/entry-common.c:758
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590

Showing all locks held in the system:
locks held by khungtaskd/31: 1, last CPU#1:
 #0: ffff800088de2060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff800088de2060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff800088de2060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6837
locks held by pr/ttyAMA-1/41: 2, last CPU#0:
 #0: ffff800088cbf158 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
 #0: ffff800088cbf158 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
 #0: ffff800088cbf158 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x4c/0x68 kernel/printk/printk.c:291
 #1: ffff0000c2eb7098 (&port_lock_key){....}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline]
 #1: ffff0000c2eb7098 (&port_lock_key){....}-{3:3}, at: pl011_console_device_lock+0x90/0xe4 drivers/tty/serial/amba-pl011.c:2715
locks held by getty/4486: 2, on CPU#0:
 #0: ffff0000cd7900a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000925de2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf78 drivers/tty/n_tty.c:2211
locks held by kworker/u9:2/4708: 3, on CPU#0:
 #0: ffff0000d6a61140 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3362 [inline]
 #0: ffff0000d6a61140 ((wq_completion)hci2){+.+.}-{0:0}, at: process_scheduled_works+0x8c8/0x1250 kernel/workqueue.c:3470
 #1: ffff800099937c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3362 [inline]
 #1: ffff800099937c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x8d0/0x1250 kernel/workqueue.c:3470
 #2: ffff0000f815cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x178/0x374 net/bluetooth/hci_sync.c:331
locks held by udevd/8924: 1, on CPU#1:
 #0: ffff0000c7695350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xc4/0x880 block/bdev.c:990
locks held by syz.2.931/9550: 1, on CPU#0:
 #0: ffff0000c7695350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x214/0x3d4 block/bdev.c:1369
locks held by syz.2.931/9552: 1, on CPU#1:
 #0: ffff0000c7695350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x214/0x3d4 block/bdev.c:1369

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