INFO: task kworker/u4:2:148 blocked for more than 145 seconds. Not tainted 5.15.167-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack: 0 pid: 148 ppid: 2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-7:0) 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_background_flush fs/fs-writeback.c:2172 [inline] wb_do_writeback fs/fs-writeback.c:2260 [inline] wb_workfn+0xc44/0x1070 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: 2 locks held by kworker/1:1/25: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001bd57c00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 1 lock held by khungtaskd/27: #0: ffff800014c917e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311 4 locks held by kworker/u4:2/148: #0: ffff0000c21d8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001d6c7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000c9f580e0 (&type->s_umount_key#59){++++}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:418 #3: ffff0000d9d4d108 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528 2 locks held by kworker/u4:3/265: 4 locks held by kworker/u4:4/347: #0: ffff0000c03f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001dba7c00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff800016be7090 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf4/0x9bc net/core/net_namespace.c:561 #3: ffff800016bf2868 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72 2 locks held by kworker/1:2/1533: #0: ffff0000c0021938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800023b57c00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 4 locks held by syslogd/3625: 4 locks held by klogd/3629: 2 locks held by getty/3785: #0: ffff0000d3fda098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340 #1: ffff80001d57e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158 3 locks held by kworker/u4:9/4139: #0: ffff0000c0029138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001fef7c00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff800016bf2868 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72 4 locks held by kworker/u4:11/4292: #0: ffff0000c21d8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020367c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000cb08e0e0 (&type->s_umount_key#59){++++}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:418 #3: ffff0000d9405108 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528 5 locks held by syz.0.61/4396: 3 locks held by syz-executor/4570: #0: ffff0000cb354ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737 #1: ffff0000cb354078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x338/0x1060 net/bluetooth/hci_core.c:1782 #2: ffff800016d361a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffff800016d361a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 5 locks held by syz.4.152/4729: 1 lock held by syz-executor/4714: #0: ffff800014c95cf0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x54/0x4b0 kernel/rcu/tree.c:4039 3 locks held by syz-executor/4739: #0: ffff800016be7090 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2d8/0x5e0 net/core/net_namespace.c:472 #1: ffff800016bf2868 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:72 #2: ffff800014c95de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffff800014c95de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x660 kernel/rcu/tree_exp.h:845 4 locks held by kworker/u5:5/4743: #0: ffff0000db786138 ((wq_completion)hci12#2){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020617c00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285