INFO: task kworker/u8:1:12 blocked for more than 144 seconds. Not tainted 6.12.0-next-20241128-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:1 state:D stack:20024 pid:12 tgid:12 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:7) Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108 write_inode fs/fs-writeback.c:1525 [inline] __writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745 writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2047 wb_writeback+0x427/0xb80 fs/fs-writeback.c:2158 wb_check_background_flush fs/fs-writeback.c:2228 [inline] wb_do_writeback fs/fs-writeback.c:2316 [inline] wb_workfn+0xc4b/0x1080 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task kworker/u8:7:1509 blocked for more than 146 seconds. Not tainted 6.12.0-next-20241128-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:7 state:D stack:23280 pid:1509 tgid:1509 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108 write_inode fs/fs-writeback.c:1525 [inline] __writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745 writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2047 wb_writeback+0x427/0xb80 fs/fs-writeback.c:2158 wb_check_background_flush fs/fs-writeback.c:2228 [inline] wb_do_writeback fs/fs-writeback.c:2316 [inline] wb_workfn+0xc4b/0x1080 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 4 locks held by kworker/u8:1/12: #0: ffff888020a8c948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888020a8c948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90000117d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000117d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffff888011c280e0 (&type->s_umount_key#83){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 #3: ffff88806e76a0e8 (&sbi->s_lock#2){+.+.}-{4:4}, at: exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108 1 lock held by khungtaskd/30: #0: ffffffff8e937b20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937b20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937b20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by kworker/u8:2/35: 3 locks held by kworker/u8:4/80: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000213fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000213fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 4 locks held by kworker/u8:7/1509: #0: ffff888020a8c948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888020a8c948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000537fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000537fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffff888024b200e0 (&type->s_umount_key#83){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 #3: ffff88802535a0e8 (&sbi->s_lock#2){+.+.}-{4:4}, at: exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108 3 locks held by kworker/u8:8/3442: #0: ffff88814c7ef948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814c7ef948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000ce97d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000ce97d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4215 6 locks held by kworker/u8:13/3565: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000d5f7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000d5f7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fca8510 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:586 #3: ffff8880271ef0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8880271ef0e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff8880271ef0e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x13b/0x440 net/devlink/core.c:506 #4: ffff8880271ec250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff8880271ec250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff8880271ec250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x14d/0x440 net/devlink/core.c:506 #5: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_notifier_net+0x89/0x3a0 net/core/dev.c:1917 1 lock held by dhcpcd/5505: #0: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6923 2 locks held by getty/5587: #0: ffff888030f550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/5848: 3 locks held by syz-executor/7094: 1 lock held by syz-executor/8415: #0: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 1 lock held by syz-executor/8425: #0: ffffffff8e93d038 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d038 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 8 locks held by syz-executor/8439: #0: ffff8880351d8420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff8880351d8420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff888060dc9488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff8880264a4878 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f560f88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88806072c0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88806072c0e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88806072c0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff888060728250 (&devlink->lock_key#14){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675 #6: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:816 #7: ffffffff8e93d038 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #7: ffffffff8e93d038 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 2 locks held by syz-executor/8444: #0: ffffffff8f43c3c0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8f43c3c0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8f43c3c0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fcb4988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd04/0x24f0 net/core/rtnetlink.c:4006 3 locks held by syz-executor/8457: #0: ffff88804d518d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88804d518d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff88804d518078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x5c8/0x11c0 net/bluetooth/hci_sync.c:5200 #2: ffffffff8fe152e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2047 [inline] #2: ffffffff8fe152e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-next-20241128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted 6.12.0-next-20241128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:match_held_lock+0x77/0xb0 kernel/locking/lockdep.c:5326 Code: c7 c2 40 c7 c3 93 48 29 d0 48 c1 f8 03 48 ba 29 5c 8f c2 f5 28 5c 8f 48 0f af d0 bd 01 00 00 00 48 39 ca 74 02 31 ed 89 e8 5b <5d> c3 cc cc cc cc 90 e8 0d 99 f4 f8 85 c0 74 22 83 3d 66 eb 45 04 RSP: 0018:ffffc90000ab7a10 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000002 RCX: ffffc90000ab7a03 RDX: 1ffff92000156f54 RSI: ffffffff8e937b20 RDI: ffff88801dea4730 RBP: 0000000000000001 R08: ffffffff90199eb7 R09: 1ffffffff20333d6 R10: dffffc0000000000 R11: fffffbfff20333d7 R12: 000000000000000a R13: 0000000000000002 R14: ffff88801dea4730 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f642ee67866 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_held_lock kernel/locking/lockdep.c:5339 [inline] __lock_release kernel/locking/lockdep.c:5524 [inline] lock_release+0x285/0xa30 kernel/locking/lockdep.c:5870 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x28b/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244