INFO: ta
INFO: task syz.3.906:9411 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.906       state:D stack:0     pid:9411  tgid:9409  ppid:8672   task_flags:0x400140 flags:0x00000011
Call trace:
 __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:810 (T)
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1c04/0x2db8 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7283
 schedule_timeout+0xc0/0x28c kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common+0x220/0x394 kernel/sched/completion.c:132
 wait_for_completion+0x18/0x24 kernel/sched/completion.c:153
 __flush_work+0x820/0xa24 kernel/workqueue.c:4366
 flush_work+0x34/0x48 kernel/workqueue.c:4387
 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline]
 p9_conn_destroy net/9p/trans_fd.c:804 [inline]
 p9_fd_close+0x1d8/0x380 net/9p/trans_fd.c:840
 p9_client_create+0x4ac/0xa40 net/9p/client.c:937
 v9fs_session_init+0x58/0x9f4 fs/9p/v9fs.c:446
 v9fs_get_tree+0xc4/0x8e8 fs/9p/vfs_super.c:97
 vfs_get_tree+0x90/0x28c fs/super.c:1754
 fc_mount+0x24/0xac fs/namespace.c:1193
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x2a4/0x538 fs/namespace.c:3834
 path_mount+0x5f0/0xa88 fs/namespace.c:4154
 do_mount+0xe8/0x148 fs/namespace.c:4167
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount fs/namespace.c:4360 [inline]
 __arm64_sys_mount+0x334/0x380 fs/namespace.c:4360
 __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:
2 locks held by kworker/0:0/9:
 #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x734/0x10b8 kernel/workqueue.c:3397
 #1: ffff80008eb17c40 (p9_poll_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #1: ffff80008eb17c40 (p9_poll_work){+.+.}-{0:0}, at: process_scheduled_works+0x73c/0x10b8 kernel/workqueue.c:3397
1 lock held by khungtaskd/31:
 #0: ffff800088bf70c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff800088bf70c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffff800088bf70c0 (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/4488:
 #0: ffff0000cfe0c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000923ab2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf70 drivers/tty/n_tty.c:2211

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