INFO: task syz.7.535:7416 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.7.535 state:D stack:0 pid:7416 tgid:7415 ppid:6731 task_flags:0x400140 flags:0x00000019 Call trace: __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:810 (T) context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1b74/0x2d24 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0xa4/0x140 kernel/sched/core.c:7282 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7339 __mutex_lock_common+0x98c/0x20f4 kernel/locking/mutex.c:726 __mutex_lock kernel/locking/mutex.c:820 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:873 bdev_release+0x128/0x32c block/bdev.c:1136 blkdev_release+0x20/0x34 block/fops.c:705 __fput+0x340/0x744 fs/file_table.c:510 ____fput+0x20/0x30 fs/file_table.c:538 task_work_run+0x1c4/0x254 kernel/task_work.c:233 get_signal+0xf30/0x1094 kernel/signal.c:2809 arch_do_signal_or_restart+0x284/0x43bc arch/arm64/kernel/signal.c:1665 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x70/0x17c kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] exit_to_user_mode_prepare_legacy include/linux/irq-entry-common.h:224 [inline] arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:86 [inline] el0_svc+0x180/0x25c arch/arm64/kernel/entry-common.c:724 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:742 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: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: __ll_sc_atomic64_fetch_or arch/arm64/include/asm/atomic_ll_sc.h:-1 [inline] #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: arch_atomic64_fetch_or arch/arm64/include/asm/atomic.h:86 [inline] #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: raw_atomic64_fetch_or include/linux/atomic/atomic-arch-fallback.h:3816 [inline] #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: raw_atomic_long_fetch_or include/linux/atomic/atomic-long.h:1090 [inline] #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: arch_test_and_set_bit include/asm-generic/bitops/atomic.h:42 [inline] #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline] #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x0/0x44 kernel/sched/sched.h:3869 2 locks held by pr/ttyAMA-1/41: 2 locks held by getty/4447: #0: ffff0000d46ca0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80009228b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x354/0xf84 drivers/tty/n_tty.c:2211 1 lock held by udevd/6357: #0: ffff0000c8c6a350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xcc/0x8cc block/bdev.c:953 1 lock held by syz.7.535/7416: #0: ffff0000c8c6a350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x128/0x32c block/bdev.c:1136 =============================================