INFO: task syz.2.2030:10250 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.2.2030 state:D stack:0 pid:10250 tgid:10248 ppid:4718 task_flags:0x400040 flags:0x00800001 Call trace: __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T) context_switch kernel/sched/core.c:5533 [inline] __schedule+0x135c/0x2b00 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x13c/0x20c kernel/sched/core.c:7376 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7433 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x5d4/0x1078 kernel/locking/mutex.c:821 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874 bdev_open+0xc4/0x880 block/bdev.c:990 blkdev_open+0x2d4/0x408 block/fops.c:674 do_dentry_open+0x5c4/0xfbc fs/open.c:996 vfs_open+0x44/0x2dc fs/open.c:1101 do_open fs/namei.c:4837 [inline] path_openat+0x1084/0x18f0 fs/namei.c:5000 do_file_open+0x1c8/0x2e8 fs/namei.c:5029 do_sys_openat2+0x114/0x1e8 fs/open.c:1417 do_sys_open+0xb0/0xe0 fs/open.c:1423 __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __arm64_sys_openat+0xa8/0xc4 fs/open.c:1434 __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:796 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 Showing all locks held in the system: locks held by kworker/0:1/10: 1, last CPU#0: #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: process_scheduled_works+0x698/0x1250 kernel/workqueue.c:3479 locks held by khungtaskd/31: 1, last CPU#0: #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff800088c618e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6871 locks held by udevd/4696: 1, on CPU#0: #0: ffff0000c7450350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xc4/0x880 block/bdev.c:990 locks held by getty/8512: 2, on CPU#0: #0: ffff0000d0b110a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff800095a772e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf78 drivers/tty/n_tty.c:2211 locks held by syz.2.2030/10250: 1, on CPU#0: #0: ffff0000c7450350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xc4/0x880 block/bdev.c:990 =============================================