INFO: task kworker/u8:0:12 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00069-g81e4f8d68c66 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:20792 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 rtnl_net_lock include/linux/rtnetlink.h:129 [inline] addrconf_dad_work+0x10e/0x16a0 net/ipv6/addrconf.c:4193 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by kthreadd/2: 3 locks held by kworker/0:0/9: 3 locks held by kworker/u8:0/12: #0: ffff88814dc57148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88814dc57148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000117c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000117c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8fed5f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fed5f08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x10e/0x16a0 net/ipv6/addrconf.c:4193 2 locks held by kworker/u8:1/13: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000127c60 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000127c60 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 2 locks held by kworker/1:0/26: 1 lock held by khungtaskd/31: #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 4 locks held by kworker/u8:2/36: #0: ffff888028868948 ((wq_completion)wg-kex-wg1#15){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888028868948 ((wq_completion)wg-kex-wg1#15){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000ac7c60 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000ac7c60 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff8880341ed308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x105/0xc90 drivers/net/wireguard/noise.c:529 #3: ffff8880499ab2b8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x116/0xc90 drivers/net/wireguard/noise.c:530 2 locks held by kworker/1:1/48: 3 locks held by kworker/u8:3/54: 3 locks held by kworker/u8:4/63: 2 locks held by kswapd0/90: 3 locks held by kworker/u8:5/970: 3 locks held by kworker/0:2/976: #0: ffff888060e90948 ((wq_completion)wg-kex-wg0#3){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888060e90948 ((wq_completion)wg-kex-wg0#3){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003ccfc60 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((typeof(*((worker))) *)(( unsigned long)((worker)))); (typeof((typeof(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003ccfc60 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((typeof(*((worker))) *)(( unsigned long)((worker)))); (typeof((typeof(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff88807de9a938 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_begin_session+0x38/0xc00 drivers/net/wireguard/noise.c:822 3 locks held by kworker/u8:6/1143: 3 locks held by kworker/u8:7/1166: 4 locks held by kworker/1:2/1207: 2 locks held by kworker/R-bat_e/3399: 3 locks held by syslogd/5189: 2 locks held by udevd/5207: 2 locks held by dhcpcd/5501: 2 locks held by getty/5592: #0: ffff88814f3a80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 1 lock held by kworker/u9:4/5839: #0: ffffffff8eb701d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x6af/0x2940 kernel/exit.c:895 1 lock held by udevd/5843: 4 locks held by syz-executor/5850: 2 locks held by kworker/0:3/5887: 5 locks held by kworker/0:4/5888: 3 locks held by kworker/1:5/5889: 5 locks held by kworker/1:6/5890: 4 locks held by kworker/1:7/5891: 3 locks held by kworker/0:5/5895: #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90004207c60 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004207c60 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8fed5f08 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x99/0xfb0 net/wireless/reg.c:2481 2 locks held by kworker/0:6/5897: 4 locks held by kworker/0:7/5900: #0: ffff88804b421948 ((wq_completion)wg-kex-wg1#16){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88804b421948 ((wq_completion)wg-kex-wg1#16){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc900041f7c60 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((typeof(*((worker))) *)(( unsigned long)((worker)))); (typeof((typeof(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900041f7c60 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((typeof(*((worker))) *)(( unsigned long)((worker)))); (typeof((typeof(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff8880341ed308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x158/0xd40 drivers/net/wireguard/noise.c:598 #3: ffff8880499ab2b8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x6fd/0xd40 drivers/net/wireguard/noise.c:632 2 locks held by kworker/0:8/5901: 3 locks held by kworker/0:9/5902: 4 locks held by kworker/1:8/6452: 1 lock held by kworker/R-wg-cr/8026: #0: ffffffff8e9e46e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x31/0x390 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/8034: #0: ffffffff8e9e46e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x31/0x390 kernel/workqueue.c:2678 5 locks held by syz-executor/8096: 1 lock held by kworker/R-wg-cr/8132: #0: ffffffff8e9e46e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x31/0x390 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/8133: #0: ffffffff8e9e46e8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x31/0x390 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/8136: 6 locks held by syz.7.607/8232: 1 lock held by syz.5.612/8260: #0: ffffffff8fed5f08 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fed5f08 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 3 locks held by syz-executor/8259: 4 locks held by kworker/u8:8/8261: 3 locks held by kworker/u8:9/8262: 2 locks held by kworker/1:9/8263: 3 locks held by kworker/0:10/8265: 3 locks held by syz-executor/8264: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00069-g81e4f8d68c66 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 1166 Comm: kworker/u8:7 Not tainted 6.14.0-rc7-syzkaller-00069-g81e4f8d68c66 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:230 [inline] RIP: 0010:__lock_acquire+0x12be/0x2100 kernel/locking/lockdep.c:5225 Code: 10 8b 18 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 40 d8 54 94 be 08 00 00 00 e8 fa 35 8c 00 48 0f a3 1d b2 eb b7 12 <73> 1d 48 69 c3 c8 00 00 00 48 8d 98 00 57 ec 93 48 ba 00 00 00 00 RSP: 0018:ffffc900000077d0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 000000000000070e RCX: ffffffff819cec86 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9454d920 RBP: c36bf112d264b906 R08: ffffffff9454d927 R09: 1ffffffff28a9b24 R10: dffffc0000000000 R11: fffffbfff28a9b25 R12: ffff8880274f3c00 R13: ffff8880274f3c00 R14: 1ffff11004e9e8ec R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f594bc05ff8 CR3: 000000000e938000 CR4: 00000000003526f0 DR0: 0000000000000006 DR1: 0000000000000004 DR2: 000000000000002f DR3: 0000000000000008 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] backlog_lock_irq_disable net/core/dev.c:241 [inline] process_backlog+0xbc8/0x15b0 net/core/dev.c:6368 __napi_poll+0xcb/0x490 net/core/dev.c:7191 napi_poll net/core/dev.c:7260 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7382 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 do_softirq+0x11b/0x1e0 kernel/softirq.c:462 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:389 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:42 [inline] wg_packet_handshake_send_worker+0x1e5/0x330 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244