INFO: task syz.4.137:4632 blocked for more than 143 seconds. Not tainted 5.15.170-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.137 state:D stack: 0 pid: 4632 ppid: 4037 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:1057 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: ffff800014c922e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311 2 locks held by kworker/u4:1/136: #0: ffff0000c0029138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001d617c00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 4 locks held by kworker/u4:4/432: #0: ffff0000c038c138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020347c00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff800016be8390 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf4/0x9bc net/core/net_namespace.c:561 #3: ffff800014c967f0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x54/0x4b0 kernel/rcu/tree.c:4039 3 locks held by kworker/u4:7/707: 2 locks held by getty/3788: #0: ffff0000d3844098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340 #1: ffff80001d61e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158 2 locks held by udevd/4018: #0: ffff0000cbc0c118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912 #1: ffff0000cbc89468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x58/0x210 drivers/block/loop.c:2070 3 locks held by kworker/0:6/4101: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020477c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000d778f240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x274/0x33c4 drivers/net/netdevsim/fib.c:1478 3 locks held by syz.4.137/4621: 1 lock held by syz.4.137/4632: #0: ffff0000ce3e1770 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x128/0x170 fs/file.c:1057 1 lock held by syz-executor/7027: 2 locks held by syz.0.880/7192: 2 locks held by syz.2.881/7194: 1 lock held by syz.5.883/7201: #0: ffff0000cbc0c118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x12c/0x89c block/bdev.c:817 =============================================