INFO: task syz.0.123:4612 blocked for more than 143 seconds. Not tainted 5.15.167-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.123 state:D stack: 0 pid: 4612 ppid: 4030 flags:0x00000001 Call trace: __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518 context_switch kernel/sched/core.c:5027 [inline] __schedule+0xf10/0x1e48 kernel/sched/core.c:6373 schedule+0x11c/0x1c8 kernel/sched/core.c:6456 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6515 __mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743 __fdget_pos+0x128/0x170 fs/file.c:1084 fdget_pos include/linux/file.h:75 [inline] ksys_read+0x8c/0x26c fs/read_write.c:614 __do_sys_read fs/read_write.c:633 [inline] __se_sys_read fs/read_write.c:631 [inline] __arm64_sys_read+0x7c/0x90 fs/read_write.c:631 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffff800014c917e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311 1 lock held by udevd/3640: 2 locks held by getty/3781: #0: ffff0000d4b9a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340 #1: ffff80001d60e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158 2 locks held by kworker/u4:14/4568: #0: ffff0001b41c1918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:475 [inline] #0: ffff0001b41c1918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1326 [inline] #0: ffff0001b41c1918 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1621 [inline] #0: ffff0001b41c1918 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x328/0x1e48 kernel/sched/core.c:6287 #1: ffff0001b41aec48 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x438/0x66c kernel/sched/psi.c:891 2 locks held by syz.0.123/4595: 1 lock held by syz.0.123/4612: #0: ffff0000cda1b770 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x128/0x170 fs/file.c:1084 3 locks held by kworker/u4:15/5161: 1 lock held by udevd/5376: #0: ffff0000cb5db118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x12c/0x89c block/bdev.c:817 1 lock held by syz-executor/6202: #0: ffff800014c95de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #0: ffff800014c95de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x660 kernel/rcu/tree_exp.h:845 2 locks held by syz.3.596/6641: #0: ffff0000cb5db118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912 #1: ffff0000cb54f468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x58/0x210 drivers/block/loop.c:2070 5 locks held by dhcpcd-run-hook/6646: =============================================