INFO: task kworker/u4:12:4491 blocked for more than 145 seconds. Not tainted 5.15.173-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:12 state:D stack: 0 pid: 4491 ppid: 2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-7:2) 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 rwsem_down_write_slowpath+0xd94/0x17e0 kernel/locking/rwsem.c:1165 __down_write_common kernel/locking/rwsem.c:1292 [inline] __down_write kernel/locking/rwsem.c:1301 [inline] down_write+0xe8/0x12c kernel/locking/rwsem.c:1552 f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528 f2fs_write_inode+0x42c/0x4a0 fs/f2fs/inode.c:736 write_inode fs/fs-writeback.c:1495 [inline] __writeback_single_inode+0x584/0x13a4 fs/fs-writeback.c:1705 writeback_sb_inodes+0x94c/0x1654 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x110/0x39c fs/fs-writeback.c:2001 wb_writeback+0x410/0xfc8 fs/fs-writeback.c:2106 wb_check_old_data_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2259 [inline] wb_workfn+0xbb4/0x1070 fs/fs-writeback.c:2288 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 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 3 locks held by kworker/u4:3/270: #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: ffff0001b41b0558 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x67c/0xd30 kernel/time/timer.c:1043 2 locks held by getty/3797: #0: ffff0000d407e098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340 #1: ffff80001d68e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158 3 locks held by kworker/0:3/3821: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001de57c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000e3406240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x274/0x33c4 drivers/net/netdevsim/fib.c:1480 3 locks held by syz-executor/4032: #0: ffff0000dd610ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737 #1: ffff0000dd610078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x338/0x1060 net/bluetooth/hci_core.c:1782 #2: ffff800016d37828 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffff800016d37828 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 3 locks held by kworker/0:6/4080: #0: ffff0000d2a2ed38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff8000203e7c00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff800016bf3ea8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72 4 locks held by kworker/u4:12/4491: #0: ffff0000c21d0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020937c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000ce2a00e0 (&type->s_umount_key#72){++++}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:418 #3: ffff0000c20851b0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528 3 locks held by kworker/1:13/5037: 3 locks held by kworker/1:14/5038: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020977c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000e326f240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x274/0x33c4 drivers/net/netdevsim/fib.c:1480 4 locks held by kworker/u4:15/5829: #0: ffff0000c038c138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020a47c00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff800016be8690 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf4/0x9bc net/core/net_namespace.c:561 #3: ffff800016bf3ea8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72 6 locks held by syz.2.557/6055: 2 locks held by syz-executor/6502: #0: ffff0000cbc25118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912 #1: ffff0000cbc91468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa8/0x9b8 drivers/block/loop.c:1365 3 locks held by kworker/u4:18/7459: 1 lock held by syz-executor/7976: 1 lock held by syz-executor/8006: 1 lock held by syz.0.975/8130: =============================================