INFO: task kworker/u8:3:53 blocked for more than 156 seconds. Not tainted 6.15.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:24216 pid:53 tgid:53 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] unregister_netdevice_notifier_net+0x1c/0xf0 net/core/dev.c:2058 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:172 cleanup_net+0x5c1/0xb30 net/core/net_namespace.c:654 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/0:5:5873 blocked for more than 156 seconds. Not tainted 6.15.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:5 state:D stack:26264 pid:5873 tgid:5873 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_power_efficient crda_timeout_work Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746 crda_timeout_work+0x15/0x50 net/wireless/reg.c:541 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.3.37:6070 blocked for more than 156 seconds. Not tainted 6.15.0-rc4-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.37 state:D stack:28344 pid:6070 tgid:6070 ppid:5834 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x62f/0xb60 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0xef/0x480 kernel/locking/rwsem.c:1526 mmap_read_lock include/linux/mmap_lock.h:184 [inline] exit_mm kernel/exit.c:565 [inline] do_exit+0x8bf/0x2c30 kernel/exit.c:940 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7a0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f729d58e9a3 RSP: 002b:00007ffdda26d638 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: fffffffffffffffc RBX: 00007f729bbf76c0 RCX: 00007f729d58e9a3 RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffdda26d790 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by kthreadd/2: 1 lock held by kworker/R-kvfre/6: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 3 locks held by kworker/0:0/9: 3 locks held by kworker/0:1/10: #0: ffff88801b481d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900000f7d18 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90125128 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x83/0x1170 net/wireless/reg.c:2483 3 locks held by kworker/u8:0/12: 3 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 3 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 5 locks held by kworker/u8:2/36: 4 locks held by kworker/1:1/47: 4 locks held by kworker/u8:3/53: #0: ffff88801c2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90000be7d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff9010f290 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xc9/0xb30 net/core/net_namespace.c:608 #3: ffffffff90125128 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #3: ffffffff90125128 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_notifier_net+0x1c/0xf0 net/core/dev.c:2058 3 locks held by kworker/u8:4/63: 3 locks held by kworker/0:2/124: 3 locks held by kworker/u8:5/131: 3 locks held by kworker/u8:6/1157: 3 locks held by kworker/R-ipv6_/3169: #0: ffff888030905948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000ba67cb0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90125128 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90125128 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4735 1 lock held by kworker/R-bat_e/3399: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 3 locks held by kworker/u8:7/3440: 3 locks held by kworker/u8:8/3472: 7 locks held by kworker/u8:9/3522: 5 locks held by kworker/u9:1/5143: #0: ffff888035569148 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000f107d18 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888032b30d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 #3: ffff888032b30078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x146/0xb40 net/bluetooth/hci_sync.c:5597 #4: ffffffff90394208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2051 [inline] #4: ffffffff90394208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x14f/0x330 net/bluetooth/hci_conn.c:1269 4 locks held by kworker/R-ext4-/5166: #0: ffff888034c5b148 ((wq_completion)ext4-rsv-conversion){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000f4c7cb0 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88814dd10950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 #3: ffff88807a812080 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x355/0x1390 fs/ext4/inode.c:705 3 locks held by syslogd/5185: 2 locks held by udevd/5203: 2 locks held by dhcpcd/5496: 1 lock held by dhcpcd/5497: 2 locks held by getty/5587: #0: ffff8880312660a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5818: 3 locks held by kworker/0:3/5823: 5 locks held by kworker/u9:2/5833: #0: ffff888027a60148 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90003edfd18 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88807db68d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 #3: ffff88807db68078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x146/0xb40 net/bluetooth/hci_sync.c:5597 #4: ffffffff90394208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2051 [inline] #4: ffffffff90394208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x14f/0x330 net/bluetooth/hci_conn.c:1269 7 locks held by kworker/u9:5/5839: 1 lock held by kworker/R-wg-cr/5859: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/5861: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/5862: 1 lock held by kworker/R-wg-cr/5863: 1 lock held by kworker/R-wg-cr/5864: 1 lock held by kworker/R-wg-cr/5865: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/5866: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/5867: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/5868: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/5869: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/5870: #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e276f48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 4 locks held by kworker/0:4/5871: 3 locks held by kworker/1:3/5872: 3 locks held by kworker/0:5/5873: #0: ffff88801b481d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900040efd18 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90125128 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x15/0x50 net/wireless/reg.c:541 3 locks held by kworker/1:4/5890: 2 locks held by syz.0.28/6026: 1 lock held by syz.1.36/6069: #0: ffff88803157ef18 (sk_lock-AF_TIPC){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline] #0: ffff88803157ef18 (sk_lock-AF_TIPC){+.+.}-{0:0}, at: tipc_sendmsg+0x41/0x70 net/tipc/socket.c:1398 4 locks held by syz.1.36/6072: 2 locks held by syz.1.36/6073: 1 lock held by syz.1.36/6076: 1 lock held by syz.3.37/6070: #0: ffff8880331b8be0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:184 [inline] #0: ffff8880331b8be0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm kernel/exit.c:565 [inline] #0: ffff8880331b8be0 (&mm->mmap_lock){++++}-{4:4}, at: do_exit+0x8bf/0x2c30 kernel/exit.c:940 3 locks held by syz.3.37/6071: 3 locks held by syz.2.38/6075: 3 locks held by kworker/u8:10/6081: 3 locks held by kworker/1:6/6082: 1 lock held by kworker/0:6/6084: 2 locks held by udevd/6085: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: bat_events batadv_tt_purge RIP: 0010:trace_hardirqs_on+0xb/0x40 kernel/trace/trace_preemptirq.c:72 Code: 0f 0b 90 e9 3e ff ff ff e8 c2 bf 5c 00 eb 8a 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 8b 05 09 aa e1 11 <85> c0 75 0e e8 6c 14 d5 ff 48 8b 3c 24 e9 83 42 a6 09 48 8b 3c 24 RSP: 0018:ffffc90000a08890 EFLAGS: 00000006 RAX: 0000000000000001 RBX: ffffffff9acc1650 RCX: ffffffff8197f623 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffffff9acc1650 RBP: 0000000000000286 R08: 0000000000000000 R09: fffffbfff35982ca R10: ffffffff9acc1653 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880310f7a00 FS: 0000000000000000(0000) GS:ffff888124aef000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005637ed9de7e5 CR3: 0000000033b50000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline] debug_check_no_obj_freed+0x31f/0x600 lib/debugobjects.c:1129 slab_free_hook mm/slub.c:2329 [inline] slab_free mm/slub.c:4656 [inline] kmem_cache_free+0x2af/0x4d0 mm/slub.c:4758 kfree_skbmem+0x1a4/0x1f0 net/core/skbuff.c:1120 __kfree_skb net/core/skbuff.c:1177 [inline] sk_skb_reason_drop+0x136/0x1a0 net/core/skbuff.c:1214 kfree_skb_reason include/linux/skbuff.h:1279 [inline] kfree_skb include/linux/skbuff.h:1288 [inline] ip6_mc_input+0x780/0xfd0 net/ipv6/ip6_input.c:591 dst_input include/net/dst.h:469 [inline] dst_input include/net/dst.h:467 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ipv6_rcv+0x45a/0x680 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5887 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6000 process_backlog+0x442/0x15e0 net/core/dev.c:6352 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7324 napi_poll net/core/dev.c:7388 [inline] net_rx_action+0xa97/0x1010 net/core/dev.c:7510 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 do_softirq kernel/softirq.c:480 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:467 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_global_purge net/batman-adv/translation-table.c:2250 [inline] batadv_tt_purge+0x25f/0xb80 net/batman-adv/translation-table.c:3510 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245