INFO: task kworker/u8:9:4637 blocked for more than 143 seconds. Not tainted 6.12.0-syzkaller-g7b1d1d4cfac0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:9 state:D stack:0 pid:4637 tgid:4637 ppid:2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-7:3) Call trace: __switch_to+0x414/0x788 arch/arm64/kernel/process.c:701 (T) context_switch kernel/sched/core.c:5328 [inline] __schedule+0x16e0/0x27d0 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0xbc/0x238 kernel/sched/core.c:6785 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6842 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:684 __mutex_lock kernel/locking/mutex.c:752 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:804 exfat_write_inode+0xa4/0x158 fs/exfat/inode.c:108 write_inode fs/fs-writeback.c:1503 [inline] __writeback_single_inode+0x5a4/0x156c fs/fs-writeback.c:1723 writeback_sb_inodes+0x648/0x1090 fs/fs-writeback.c:1954 __writeback_inodes_wb+0xec/0x234 fs/fs-writeback.c:2025 wb_writeback+0x400/0xf0c fs/fs-writeback.c:2136 wb_check_background_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2294 [inline] wb_workfn+0xc2c/0x104c fs/fs-writeback.c:2321 process_one_work+0x7bc/0x1600 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x97c/0xeec kernel/workqueue.c:3391 kthread+0x288/0x310 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffff80008faafee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:336 2 locks held by kworker/u8:6/490: #0: ffff0001b3655918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:598 [inline] #0: ffff0001b3655918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1506 [inline] #0: ffff0001b3655918 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1805 [inline] #0: ffff0001b3655918 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2e0/0x27d0 kernel/sched/core.c:6592 #1: ffff80009c867c20 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 4 locks held by kworker/u8:9/4637: #0: ffff0000c2076948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x628/0x1600 kernel/workqueue.c:3203 #1: ffff8000a1477c20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 #2: ffff0000ca3340e0 (&type->s_umount_key#53){++++}-{3:3}, at: super_trylock_shared+0x28/0xe4 fs/super.c:562 #3: ffff0000d96520e8 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0xa4/0x158 fs/exfat/inode.c:108 2 locks held by getty/6186: #0: ffff0000d73e90a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80009b94b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/6424: 2 locks held by kworker/u8:10/6677: #0: ffff0000c0031148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x628/0x1600 kernel/workqueue.c:3203 #1: ffff8000a26b7c20 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 1 lock held by syz-executor/6752: #0: ffff80008fab5438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffff80008fab5438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x324/0x674 kernel/rcu/tree_exp.h:976 2 locks held by kworker/u8:11/6776: #0: ffff0000c0031148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x628/0x1600 kernel/workqueue.c:3203 #1: ffff8000a09f7c20 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 3 locks held by kworker/u8:12/6921: 1 lock held by syz-executor/8460: #0: ffff0000ea0520e0 (&type->s_umount_key#58){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff0000ea0520e0 (&type->s_umount_key#58){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff0000ea0520e0 (&type->s_umount_key#58){+.+.}-{3:3}, at: deactivate_super+0xd8/0x100 fs/super.c:505 1 lock held by udevd/8462: #0: ffff800090025a28 (uuid_mutex){+.+.}-{3:3}, at: btrfs_control_ioctl+0x134/0x370 fs/btrfs/super.c:2251 2 locks held by syz.7.277/8748: #0: ffff0000ca3340e0 (&type->s_umount_key#53){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff0000ca3340e0 (&type->s_umount_key#53){++++}-{3:3}, at: super_lock+0x244/0x33c fs/super.c:120 #1: ffff0000ca4fa7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff0000ca4fa7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x208/0x9ac fs/fs-writeback.c:2797 2 locks held by syz-executor/9050: #0: ffff8000927f3628 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffff8000927f3628 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x5e8/0xa9c net/core/rtnetlink.c:6672 #1: ffff80008fab5438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #1: ffff80008fab5438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x354/0x674 kernel/rcu/tree_exp.h:976 2 locks held by syz.6.303/9086: #0: ffff800090025a28 (uuid_mutex){+.+.}-{3:3}, at: btrfs_get_tree_super fs/btrfs/super.c:1843 [inline] #0: ffff800090025a28 (uuid_mutex){+.+.}-{3:3}, at: btrfs_get_tree+0x240/0x131c fs/btrfs/super.c:2107 #1: ffff80008fb5ddc8 (lock#2){+.+.}-{3:3}, at: __lru_add_drain_all+0x88/0x50c mm/swap.c:829 1 lock held by dhcpcd/9104: #0: ffff0000cd946258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1611 [inline] #0: ffff0000cd946258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x4c/0xb2c net/packet/af_packet.c:3266 1 lock held by dhcpcd/9105: #0: ffff0000cd040258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1611 [inline] #0: ffff0000cd040258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x4c/0xb2c net/packet/af_packet.c:3266 1 lock held by dhcpcd/9106: #0: ffff0000cd042258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1611 [inline] #0: ffff0000cd042258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x4c/0xb2c net/packet/af_packet.c:3266 1 lock held by dhcpcd/9107: #0: ffff0000c8e36258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1611 [inline] #0: ffff0000c8e36258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x4c/0xb2c net/packet/af_packet.c:3266 =============================================