INFO: task kworker/u8:4:60 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-syzkaller-00193-g40f92e79b0aa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:4 state:D stack:24280 pid:60 tgid:60 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6883 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:747 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_dad_work+0x120/0x14e0 net/ipv6/addrconf.c:4193 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/0:3:5850 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-syzkaller-00193-g40f92e79b0aa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:26424 pid:5850 tgid:5850 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events reg_todo Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6883 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:747 class_wiphy_constructor include/net/cfg80211.h:6062 [inline] reg_process_self_managed_hints+0x95/0x1f0 net/wireless/reg.c:3209 reg_todo+0x66f/0x900 net/wireless/reg.c:3222 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by kthreadd/2: 4 locks held by kworker/0:1/10: 3 locks held by kworker/u8:0/12: 3 locks held by kworker/u8:1/13: 2 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4d00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4d00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4d00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:2/36: 3 locks held by kworker/u8:3/49: 3 locks held by kworker/u8:4/60: #0: ffff88814c491948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000211fd10 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x120/0x14e0 net/ipv6/addrconf.c:4193 3 locks held by kworker/u8:5/80: 3 locks held by kworker/0:2/979: #0: ffff88801b881d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900037ffd10 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x15/0x50 net/wireless/reg.c:541 3 locks held by kworker/u8:6/1015: 3 locks held by kworker/R-bat_e/3413: 3 locks held by kworker/u8:7/3517: 3 locks held by kworker/u8:8/4526: 2 locks held by klogd/5206: 2 locks held by udevd/5217: 2 locks held by dhcpcd/5511: 2 locks held by crond/5591: 2 locks held by getty/5613: #0: ffff88814dd480a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5835: 2 locks held by syz-executor/5844: 1 lock held by syz-executor/5846: 5 locks held by kworker/u9:2/5848: #0: ffff888028412948 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90004647d10 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888033e88dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 #3: ffff888033e880b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x13f/0xb10 net/bluetooth/hci_sync.c:5670 #4: ffffffff905d5ca8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2052 [inline] #4: ffffffff905d5ca8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x14f/0x330 net/bluetooth/hci_conn.c:1275 4 locks held by kworker/0:3/5850: #0: ffff88801b880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90004667d10 (reg_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0x900 net/wireless/reg.c:3219 #3: ffff888026608768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline] #3: ffff888026608768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_process_self_managed_hints+0x95/0x1f0 net/wireless/reg.c:3209 4 locks held by kworker/u9:4/5854: #0: ffff888028414948 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900046b7d10 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888033e8cdc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 #3: ffff888033e8c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x13f/0xb10 net/bluetooth/hci_sync.c:5670 5 locks held by kworker/u9:7/5862: #0: ffff888028adb148 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90004727d10 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88803513cdc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 #3: ffff88803513c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x13f/0xb10 net/bluetooth/hci_sync.c:5670 #4: ffffffff905d5ca8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2052 [inline] #4: ffffffff905d5ca8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x14f/0x330 net/bluetooth/hci_conn.c:1275 6 locks held by kworker/u9:8/5863: #0: ffff888028ada948 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90004737d10 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888035138dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x430 net/bluetooth/hci_sync.c:331 #3: ffff8880351380b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x13f/0xb10 net/bluetooth/hci_sync.c:5670 #4: ffffffff905d5ca8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2052 [inline] #4: ffffffff905d5ca8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x14f/0x330 net/bluetooth/hci_conn.c:1275 #5: ffff888029398338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x80/0x730 net/bluetooth/l2cap_core.c:1762 3 locks held by kworker/0:4/5900: #0: ffff88801b881d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000a98fd10 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x83/0x1170 net/wireless/reg.c:2483 1 lock held by kworker/0:5/5920: 2 locks held by kworker/1:6/5939: 2 locks held by kworker/1:7/5940: 2 locks held by kworker/0:6/5946: 1 lock held by syz.0.7/5969: #0: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff903641e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3396 2 locks held by syz.2.9/5974: 4 locks held by kworker/u8:9/5975: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00193-g40f92e79b0aa #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 3413 Comm: kworker/R-bat_e Not tainted 6.16.0-rc5-syzkaller-00193-g40f92e79b0aa #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_tt_purge RIP: 0010:match_held_lock+0x78/0xc0 kernel/locking/lockdep.c:5340 Code: 1f 00 00 48 39 d0 0f 94 c0 0f b6 c0 c3 cc cc cc cc b8 01 00 00 00 5b c3 cc cc cc cc 31 f6 e8 2f fe ff ff 48 85 c0 75 a7 31 c0 <5b> e9 52 f3 02 00 90 e8 cc 48 51 f9 85 c0 74 0a 8b 05 42 70 25 05 RSP: 0018:ffffc90000006998 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff888032128b18 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8e5c4d00 RDI: ffff888032128b18 RBP: ffffffff8e5c4d00 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff888032128000 R13: ffff888032128af0 R14: 00000000ffffffff R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888124721000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5bc9c00000 CR3: 00000000339e0000 CR4: 00000000003526f0 Call Trace: __lock_is_held kernel/locking/lockdep.c:5604 [inline] lock_is_held_type+0xb0/0x150 kernel/locking/lockdep.c:5943 __find_rr_leaf+0x36c/0xe00 net/ipv6/route.c:834 find_rr_leaf net/ipv6/route.c:890 [inline] rt6_select net/ipv6/route.c:934 [inline] fib6_table_lookup+0x57c/0xa30 net/ipv6/route.c:2232 ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2268 pol_lookup_func include/net/ip6_fib.h:617 [inline] fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2337 [inline] ip6_route_input+0x662/0xc00 net/ipv6/route.c:2640 ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66 ip6_rcv_finish+0x130/0x5b0 net/ipv6/ip6_input.c:77 ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:993 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:623 nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:272 NF_HOOK include/linux/netfilter.h:315 [inline] ipv6_rcv+0xa4/0x680 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5977 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6090 netif_receive_skb_internal net/core/dev.c:6176 [inline] netif_receive_skb+0x137/0x7b0 net/core/dev.c:6235 NF_HOOK include/linux/netfilter.h:317 [inline] NF_HOOK include/linux/netfilter.h:311 [inline] br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70 br_handle_frame_finish+0xf5a/0x1ca0 net/bridge/br_input.c:227 br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:317 [inline] br_nf_pre_routing_ipv6+0x3cd/0x8c0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0xad5/0x14b0 net/bridge/br_input.c:434 __netif_receive_skb_core.constprop.0+0xa26/0x4a00 net/core/dev.c:5863 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5975 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6090 process_backlog+0x442/0x15e0 net/core/dev.c:6442 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0xa9f/0xfe0 net/core/dev.c:7605 handle_softirqs+0x219/0x8e0 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_local_purge+0x21c/0x3c0 net/batman-adv/translation-table.c:1315 batadv_tt_purge+0x8b/0xb80 net/batman-adv/translation-table.c:3509 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] rescuer_thread+0x620/0xea0 kernel/workqueue.c:3498 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245