INFO: task kworker/R-netns:8 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/R-netns state:D stack:29848 pid:8 tgid:8 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xfee/0x60e0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 wg_netns_pre_exit+0x1b/0x250 drivers/net/wireguard/device.c:419 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0x187/0xab0 net/core/net_namespace.c:234 cleanup_net+0x499/0x920 net/core/net_namespace.c:704 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] rescuer_thread+0x902/0x1490 kernel/workqueue.c:3582 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e7f4e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 4 locks held by kworker/R-netns/8: #0: ffff88801c6ae948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900000d7c70 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff905f9650 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:675 #3: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1b/0x250 drivers/net/wireguard/device.c:419 1 lock held by khungtaskd/30: #0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 1 lock held by khugepaged/37: #0: ffffffff8e939328 (lock#5){+.+.}-{4:4}, at: __lru_add_drain_all+0x6a/0x650 mm/swap.c:840 4 locks held by kworker/1:1/42: #0: ffff88803442ed48 ((wq_completion)wg-kex-wg2#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90000b27d08 ((work_completion)(&({ do { const void __seg_gs *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88802b37d348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x860 drivers/net/wireguard/noise.c:598 #3: ffff88807c7dbea8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x860 drivers/net/wireguard/noise.c:632 2 locks held by kworker/0:2/797: 4 locks held by kworker/1:2/886: #0: ffff88813fe62148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90004307d08 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x11d0 net/wireless/reg.c:2464 #3: ffff88802a3d0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline] #3: ffff88802a3d0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2452 [inline] #3: ffff88802a3d0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x12f/0x11d0 net/wireless/reg.c:2467 4 locks held by syz-executor/5810: #0: ffff888077e80588 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 #1: ffff88803413a518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3589 #2: ffff888079b50580 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline] #2: ffff888079b50580 (mapping.invalidate_lock#2){++++}-{4:4}, at: ext4_page_mkwrite+0x36c/0x1980 fs/ext4/inode.c:6618 #3: ffff888079b50270 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_map_blocks fs/ext4/inode.c:1954 [inline] #3: ffff888079b50270 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_get_block_prep+0x738/0x1240 fs/ext4/inode.c:2020 2 locks held by kworker/0:3/5812: 4 locks held by kworker/1:4/5875: #0: ffff8880344b8948 ((wq_completion)wg-kex-wg0#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900041d7d08 ((work_completion)(&({ do { const void __seg_gs *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88807ae69348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x860 drivers/net/wireguard/noise.c:598 #3: ffff88807c7df030 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x860 drivers/net/wireguard/noise.c:632 3 locks held by kworker/1:6/5914: #0: ffff88813fe63548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90004357d08 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u10:0/13144: 3 locks held by kworker/u10:1/13152: 4 locks held by kworker/u10:2/13155: 6 locks held by kworker/u10:3/13158: 3 locks held by kworker/u10:4/13167: 3 locks held by kworker/u10:5/13190: 3 locks held by kworker/u10:6/13603: 3 locks held by kworker/u10:7/13774: 2 locks held by kworker/u10:8/14186: #0: ffff88813fea4948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900034c7d08 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 1 lock held by syz.1.1903/14190: #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436 2 locks held by syz.3.1905/14196: #0: ffffffff905f9650 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 #1: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_wait_allrefs_any net/core/dev.c:11581 [inline] #1: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_run_todo+0xcd5/0x12c0 net/core/dev.c:11701 2 locks held by kworker/u10:9/14199: #0: ffff88813fea4948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90003f37d08 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 4 locks held by kworker/u10:10/14202: 4 locks held by kworker/u10:11/14203: 3 locks held by kworker/u10:12/14206: 2 locks held by syz.2.1909/14223: #0: ffffffff905f9650 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 #1: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x1b/0x70 net/ipv4/nexthop.c:3971 2 locks held by syz.0.1910/14220: #0: ffffffff905f9650 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 #1: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1b/0x250 drivers/net/wireguard/device.c:419 4 locks held by kworker/u10:13/14224: 1 lock held by syz-executor/14239: #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 2 locks held by kworker/u10:14/14245: #0: ffff88813fea4948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc9000764fd08 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 4 locks held by modprobe/14253: 2 locks held by kworker/u10:15/14254: #0: ffff88813fea4948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90003867d08 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 1 lock held by modprobe/14255: 1 lock held by modprobe/14256: 4 locks held by kworker/u10:16/14257: 2 locks held by modprobe/14259: 3 locks held by kworker/u10:17/14263: #0: ffff888034497948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90003f07d08 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4739 2 locks held by kworker/u10:18/14264: 1 lock held by syz-executor/14268: #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/14270: #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/14272: #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90611fa8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 6 locks held by kworker/u10:19/14274: 4 locks held by kworker/u10:20/14278: #0: ffff888020ec0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90004dcfd08 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88803413a0e0 (&type->s_umount_key#33){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:565 #3: ffff888034138b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x278/0x600 mm/page-writeback.c:2554 3 locks held by kworker/u10:21/14282: 1 lock held by dhcpcd/14283: #0: ffff888031254260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888031254260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3198 4 locks held by kworker/u10:22/14284: 1 lock held by dhcpcd/14286: #0: ffff888030984260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888030984260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3198 1 lock held by dhcpcd/14287: #0: ffff8880346a2260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff8880346a2260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3198 1 lock held by dhcpcd/14288: #0: ffff888027392260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888027392260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3198 2 locks held by kworker/u10:23/14289: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xd25/0x1050 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 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: 14274 Comm: kworker/u10:19 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x0/0x20 kernel/kcov.c:299 Code: 0c 24 48 89 f2 48 89 fe bf 06 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 0c 24 40 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 RSP: 0018:ffffc90000007338 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff88807c361000 RCX: ffffffff8a623986 RDX: ffff88807e350000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff888037ee4a00 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: ffff88807c361030 R14: ffff888075f0c000 R15: ffff88807c361028 FS: 0000000000000000(0000) GS:ffff888124351000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe03205ff50 CR3: 000000000e598000 CR4: 00000000003526f0 Call Trace: should_deliver+0x212/0x3d0 net/bridge/br_forward.c:28 maybe_deliver+0x5a/0x180 net/bridge/br_forward.c:183 br_flood+0x193/0x650 net/bridge/br_forward.c:238 br_handle_frame_finish+0xf57/0x1f00 net/bridge/br_input.c:229 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167 br_nf_pre_routing_finish_ipv6+0x769/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x93b/0x1510 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:291 [inline] br_handle_frame+0xcdd/0x1520 net/bridge/br_input.c:442 __netif_receive_skb_core.constprop.0+0x6c5/0x3550 net/core/dev.c:6043 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6154 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6269 process_backlog+0x37a/0x1580 net/core/dev.c:6621 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7685 napi_poll net/core/dev.c:7748 [inline] net_rx_action+0xa40/0xf20 net/core/dev.c:7900 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xac/0xe0 kernel/softirq.c:510 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline] kernel_fpu_end arch/x86/kernel/fpu/core.c:506 [inline] kernel_fpu_end+0x64/0x80 arch/x86/kernel/fpu/core.c:499 blake2s_compress+0x78/0xf0 lib/crypto/x86/blake2s.h:42 blake2s_update+0xef/0x320 lib/crypto/blake2s.c:119 hmac.constprop.0+0x33f/0x480 drivers/net/wireguard/noise.c:332 kdf.constprop.0+0x128/0x280 drivers/net/wireguard/noise.c:360 message_ephemeral+0x5e/0x70 drivers/net/wireguard/noise.c:493 wg_noise_handshake_create_initiation+0x322/0x610 drivers/net/wireguard/noise.c:545 wg_packet_send_handshake_initiation+0x19c/0x360 drivers/net/wireguard/send.c:34 wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245