INFO: task s
INFO: task syz.6.753:7848 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.6.753       state:D stack:0     pid:7848  tgid:7847  ppid:6037   task_flags:0x400140 flags:0x00000011
Call trace:
 __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7326
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7383
 __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:1297
 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:736
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
INFO: task syz.1.910:8485 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.1.910       state:D stack:0     pid:8485  tgid:8484  ppid:4721   task_flags:0x400140 flags:0x00000011
Call trace:
 __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7326
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7383
 __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:1297
 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:736
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffff800088cf7020 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff800088cf7020 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff800088cf7020 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6775
2 locks held by pr/ttyAMA-1/41:
2 locks held by getty/4493:
 #0: ffff0000cea140a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000924cb2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf78 drivers/tty/n_tty.c:2211
1 lock held by udevd/4700:
 #0: ffff0000c7c19350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xc4/0x880 block/bdev.c:948
4 locks held by kworker/u8:10/5576:
1 lock held by syz.6.753/7848:
 #0: ffff0000c7c19350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x214/0x3d4 block/bdev.c:1297
1 lock held by syz.1.910/8485:
 #0: ffff0000c7c19350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x214/0x3d4 block/bdev.c:1297

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