INFO: task kworker/0:4:5909 blocked for more than 145 seconds. Not tainted 6.16.0-syzkaller-11489-gd2eedaa3909b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:4 state:D stack:22312 pid:5909 tgid:5909 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 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: 1 lock held by kworker/R-rcu_g/4: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 1 lock held by kworker/R-kvfre/6: 2 locks held by kworker/0:0/9: 3 locks held by kworker/0:1/10: 3 locks held by kworker/u8:0/12: 5 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 6 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/36: 2 locks held by kworker/1:1/43: 3 locks held by kworker/u8:3/49: 3 locks held by kworker/u8:4/59: 3 locks held by kworker/0:2/975: 3 locks held by kworker/u8:5/1146: 3 locks held by kworker/u8:6/1154: 3 locks held by kworker/u8:7/1161: 4 locks held by kworker/1:2/3089: #0: ffff888057a43d48 ((wq_completion)wg-kex-wg1#4){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000c8e7d10 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff888057b11308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff88802b83b4c0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 1 lock held by kworker/R-mld/3197: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 3 locks held by kworker/R-ipv6_/3198: #0: ffff88814ce12148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000cac7ca8 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff9037da48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff9037da48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734 5 locks held by kworker/R-bat_e/3422: 3 locks held by kworker/u8:8/4445: 1 lock held by klogd/5207: 2 locks held by udevd/5218: 2 locks held by dhcpcd/5512: 2 locks held by dhcpcd/5513: 2 locks held by crond/5587: 2 locks held by getty/5604: #0: ffff88814dafe0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5831: 1 lock held by syz-executor/5841: #0: ffffffff8e5cc7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311 3 locks held by udevd/5842: 2 locks held by syz-executor/5849: #0: ffffffff9037da48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff9037da48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433 #1: ffff888024f89538 (&idev->mc_lock){+.+.}-{4:4}, at: __ipv6_dev_mc_dec+0x45/0x340 net/ipv6/mcast.c:997 1 lock held by udevd/5854: 2 locks held by kworker/0:3/5856: 1 lock held by kworker/R-wg-cr/5880: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 1 lock held by kworker/R-wg-cr/5883: 1 lock held by kworker/R-wg-cr/5887: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 2 locks held by kworker/R-wg-cr/5890: 1 lock held by kworker/R-wg-cr/5891: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 1 lock held by kworker/R-wg-cr/5892: 1 lock held by kworker/R-wg-cr/5893: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 1 lock held by kworker/R-wg-cr/5895: #0: ffffffff8e4783e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 3 locks held by kworker/0:4/5909: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000431fd10 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff9037da48 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/0:5/5910: 4 locks held by kworker/0:6/5918: 3 locks held by kworker/0:7/5919: 3 locks held by kworker/0:8/5961: 4 locks held by kworker/1:4/5969: 1 lock held by udevd/6045: 3 locks held by kworker/1:6/6065: 2 locks held by kworker/1:7/8004: 2 locks held by syz.3.2016/10149: 4 locks held by kworker/u8:9/10153: #0: ffff88807551e148 ((wq_completion)wg-kex-wg1#5){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90003547d10 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff8880353b1308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x650 drivers/net/wireguard/noise.c:529 #3: ffff888029f45c60 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x650 drivers/net/wireguard/noise.c:530 4 locks held by kworker/u8:10/10156: 3 locks held by kworker/u8:11/10157: #0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90003717d10 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff9037da48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303 4 locks held by kworker/u8:12/10158: 3 locks held by kworker/1:8/10159: 3 locks held by kworker/u8:13/10160: 5 locks held by kworker/1:9/10161: 2 locks held by syz-executor/10162: 3 locks held by kworker/0:9/10163: 3 locks held by syz-executor/10164: 4 locks held by kworker/u8:14/10165: 1 lock held by dhcpcd/10167: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-11489-gd2eedaa3909b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c2/0x780 kernel/kthread.c:463 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: 3422 Comm: kworker/R-bat_e Not tainted 6.16.0-syzkaller-11489-gd2eedaa3909b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_tt_purge RIP: 0010:__lock_acquire+0x0/0x1ce0 kernel/locking/lockdep.c:5081 Code: 36 8d e2 ff 90 0f 0b 90 90 eb a8 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 57 41 56 41 55 41 54 55 53 65 4c 8b 2d a6 fb 3d 12 48 83 ec 70 RSP: 0018:ffffc900000067e0 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffffffff8e5c1220 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e5c1220 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 000000000008657c R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881246c6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc4d7800218 CR3: 0000000074573000 CR4: 00000000003526f0 Call Trace: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4782 __skb_ext_put+0x102/0x2c0 net/core/skbuff.c:7153 __skb_ext_del+0xf3/0x340 net/core/skbuff.c:7120 skb_ext_del include/linux/skbuff.h:4904 [inline] nf_bridge_info_free net/bridge/br_netfilter_hooks.c:156 [inline] br_nf_dev_queue_xmit+0x7b7/0x2a80 net/bridge/br_netfilter_hooks.c:922 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_post_routing+0x8e7/0x1190 net/bridge/br_netfilter_hooks.c:969 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623 nf_hook+0x45e/0x780 include/linux/netfilter.h:273 NF_HOOK include/linux/netfilter.h:316 [inline] br_forward_finish+0xcd/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh+0x304/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_forward_finish+0x66a/0xba0 net/bridge/br_netfilter_hooks.c:665 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_forward_ip.part.0+0x609/0x810 net/bridge/br_netfilter_hooks.c:719 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:679 [inline] br_nf_forward+0xf0f/0x1be0 net/bridge/br_netfilter_hooks.c:776 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623 nf_hook+0x45e/0x780 include/linux/netfilter.h:273 NF_HOOK include/linux/netfilter.h:316 [inline] __br_forward+0x1be/0x5b0 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] br_flood+0x39c/0x650 net/bridge/br_forward.c:249 br_handle_frame_finish+0xf2d/0x1ca0 net/bridge/br_input.c:221 br_nf_hook_thresh+0x304/0x410 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:318 [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:158 [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+0xa22/0x48c0 net/core/dev.c:5866 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5977 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6092 process_backlog+0x442/0x15e0 net/core/dev.c:6444 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7497 napi_poll net/core/dev.c:7560 [inline] net_rx_action+0xa9f/0xfe0 net/core/dev.c:7687 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_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+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] rescuer_thread+0x620/0xea0 kernel/workqueue.c:3496 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245