INFO: task kworker/u4:12:3886 blocked for more than 145 seconds. Not tainted 6.1.100-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:12 state:D stack:20928 pid:3886 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:736 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974 wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079 wb_check_old_data_flush fs/fs-writeback.c:2179 [inline] wb_do_writeback fs/fs-writeback.c:2232 [inline] wb_workfn+0xbec/0x1020 fs/fs-writeback.c:2260 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d12af10 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d12b710 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/27: #0: ffffffff8d12ad40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d12ad40 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d12ad40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 2 locks held by getty/3300: #0: ffff88814ba37098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 3 locks held by kworker/u5:1/3546: #0: ffff88802118f138 ((wq_completion)hci4){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000403fd20 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff88807bf450b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1dc/0x400 net/bluetooth/hci_sync.c:308 2 locks held by kworker/1:5/3603: #0: ffff888012472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000431fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by kworker/u4:9/3690: #0: ffff88814bc92138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffff8880b9827788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x43d/0x770 kernel/sched/psi.c:1001 4 locks held by kworker/u4:12/3886: #0: ffff888017a55938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000564fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff88807f6a40e0 (&type->s_umount_key#52){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff888059429140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] #3: ffff888059429140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 5 locks held by syz.4.207/4630: 3 locks held by syz-executor/4917: #0: ffff88807bf450b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] #0: ffff88807bf450b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1cf/0x4d0 net/bluetooth/hci_core.c:2736 #1: ffff88807bf44078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0x1020 net/bluetooth/hci_sync.c:5005 #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1805 [inline] #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2441 3 locks held by kworker/0:13/5859: #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900046efd20 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d130338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d130338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 3 locks held by kworker/1:11/6766: #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900128efd20 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d130338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d130338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.4.699/6863: 3 locks held by syz.3.729/6964: #0: ffff8880587810b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] #0: ffff8880587810b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1cf/0x4d0 net/bluetooth/hci_core.c:2736 #1: ffff888058780078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0x1020 net/bluetooth/hci_sync.c:5005 #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1805 [inline] #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2441 3 locks held by syz.1.720/6971: #0: ffff888064c210b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] #0: ffff888064c210b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1cf/0x4d0 net/bluetooth/hci_core.c:2736 #1: ffff888064c20078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0x1020 net/bluetooth/hci_sync.c:5005 #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1805 [inline] #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2441 3 locks held by syz.0.730/6968: #0: ffff88807d7cd0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] #0: ffff88807d7cd0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1cf/0x4d0 net/bluetooth/hci_core.c:2736 #1: ffff88807d7cc078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0x1020 net/bluetooth/hci_sync.c:5005 #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1805 [inline] #2: ffffffff8e3f0f48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2441 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3690 Comm: kworker/u4:9 Not tainted 6.1.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:validate_chain+0xcb/0x5950 kernel/locking/lockdep.c:3792 Code: f2 00 f3 f3 4a 89 44 21 23 48 89 8c 24 a0 00 00 00 42 c6 44 21 2b f3 48 89 b4 24 b0 00 00 00 4c 8d 6e 20 4c 89 e8 48 c1 e8 03 <48> 89 44 24 68 42 0f b6 04 20 84 c0 0f 85 ba 46 00 00 41 8b 5d 00 RSP: 0018:ffffc9000478f6e0 EFLAGS: 00000802 RAX: 1ffff11004aef8da RBX: ffffffff90194260 RCX: 1ffff920008f1efc RDX: 0000000000000000 RSI: ffff88802577c6b0 RDI: ffff88802577bb80 RBP: ffffc9000478f990 R08: dffffc0000000000 R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff88802577c6d0 R14: c111a1d1859c639d R15: 1ffff11004aef8da FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020bbd030 CR3: 000000007fa7f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xe8/0x610 net/batman-adv/network-coding.c:719 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295