INFO: task kworker/0:4:13543 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-next-20250618-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:4 state:D stack:20712 pid:13543 tgid:13543 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:5313 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6696 __schedule_loop kernel/sched/core.c:6774 [inline] schedule+0x165/0x360 kernel/sched/core.c:6789 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6846 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747 class_wiphy_constructor include/net/cfg80211.h:6062 [inline] reg_leave_invalid_chans net/wireless/reg.c:2471 [inline] reg_check_chans_work+0x164/0xf00 net/wireless/reg.c:2486 process_one_work kernel/workqueue.c:3239 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 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: 2 locks held by kworker/0:1/10: 3 locks held by kworker/u8:0/12: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 1 lock held by khungtaskd/31: #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 1 lock held by kworker/R-write/33: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2679 3 locks held by kworker/u8:2/36: 4 locks held by kworker/1:1/43: 4 locks held by kworker/u8:3/49: 3 locks held by kworker/u8:4/59: 4 locks held by kworker/u8:5/66: 3 locks held by kworker/u8:8/1165: 3 locks held by kworker/R-ipv6_/3174: #0: ffff88814d213148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #0: ffff88814d213148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322 #1: ffffc9000bec7ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline] #1: ffffc9000bec7ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322 #2: ffffffff8f5177c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f5177c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4738 1 lock held by klogd/5192: 1 lock held by udevd/5203: 2 locks held by getty/5592: #0: ffff8880301d70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036ab2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5821: 1 lock held by kworker/0:3/5838: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2679 5 locks held by syz-executor/5848: 3 locks held by kworker/1:4/5910: 3 locks held by kworker/0:5/5936: 4 locks held by kworker/1:5/5939: 3 locks held by udevd/5963: 3 locks held by kworker/1:8/5981: 3 locks held by kworker/0:6/6011: 3 locks held by kworker/u8:1/12457: 4 locks held by kworker/0:4/13543: #0: ffff88801a482148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #0: ffff88801a482148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322 #1: ffffc900035e7bc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline] #1: ffffc900035e7bc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322 #2: ffffffff8f5177c8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x95/0xf00 net/wireless/reg.c:2483 #3: ffff888078790768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline] #3: ffff888078790768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2471 [inline] #3: ffff888078790768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x164/0xf00 net/wireless/reg.c:2486 3 locks held by kworker/u8:6/21502: 1 lock held by kworker/R-bond0/24021: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2679 1 lock held by kworker/R-bond2/30742: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2679 4 locks held by syz-executor/32033: 1 lock held by kworker/R-wg-cr/32153: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 1 lock held by kworker/R-wg-cr/32155: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 3 locks held by kworker/0:0/32504: 3 locks held by kworker/u8:7/335: 5 locks held by kworker/1:0/2817: 1 lock held by syz-executor/6080: 1 lock held by kworker/R-wg-cr/6181: 1 lock held by kworker/R-wg-cr/6184: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 2 locks held by kworker/0:2/6256: 2 locks held by kworker/0:7/6260: 3 locks held by kworker/0:8/6747: #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322 #1: ffffc90004937bc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline] #1: ffffc90004937bc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322 #2: ffffffff8f5177c8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u8:9/6844: 3 locks held by kworker/1:2/6907: 1 lock held by syz-executor/7207: 1 lock held by kworker/R-wg-cr/7506: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 1 lock held by kworker/R-wg-cr/7511: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 1 lock held by kworker/R-wg-cr/7515: #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2737 [inline] #0: ffffffff8dfe58a8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3532 6 locks held by syz.2.14155/9720: 1 lock held by sed/9783: 4 locks held by kworker/u8:10/9784: 4 locks held by kworker/u8:11/9785: 4 locks held by kworker/u8:12/9786: #0: ffff8880295d4148 ((wq_completion)wg-kex-wg2#12){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #0: ffff8880295d4148 ((wq_completion)wg-kex-wg2#12){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322 #1: ffffc9000bf67bc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline] #1: ffffc9000bf67bc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322 #2: ffff88804ee71308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x10a/0x7e0 drivers/net/wireguard/noise.c:529 #3: ffff888060455278 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x11b/0x7e0 drivers/net/wireguard/noise.c:530 4 locks held by kworker/u8:13/9787: #0: ffff888075bea148 ((wq_completion)wg-kex-wg1#11){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #0: ffff888075bea148 ((wq_completion)wg-kex-wg1#11){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322 #1: ffffc9000386fbc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline] #1: ffffc9000386fbc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322 #2: ffff888047685308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x10a/0x7e0 drivers/net/wireguard/noise.c:529 #3: ffff88807b16f030 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x11b/0x7e0 drivers/net/wireguard/noise.c:530 4 locks held by kworker/u8:14/9788: 1 lock held by kworker/u8:15/9790: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-next-20250618-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/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+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 49 Comm: kworker/u8:3 Not tainted 6.16.0-rc2-next-20250618-syzkaller #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:rol32 include/linux/bitops.h:126 [inline] RIP: 0010:jhash2 include/linux/jhash.h:129 [inline] RIP: 0010:hash_stack lib/stackdepot.c:514 [inline] RIP: 0010:stack_depot_save_flags+0x94/0x900 lib/stackdepot.c:615 Code: 72 6f 89 e8 89 e9 4c 89 f2 03 0a 03 42 04 03 6a 08 89 ef c1 c7 04 29 e9 31 cf 01 c5 29 f8 41 89 f8 41 c1 c0 06 41 31 c0 01 ef <45> 89 c1 41 c1 c1 08 44 29 c5 41 31 e9 41 01 f8 44 29 cf 44 89 c9 RSP: 0018:ffffc90000a08238 EFLAGS: 00000293 RAX: 00000000376477ef RBX: 0000000000000820 RCX: 00000000d0f4aed4 RDX: ffffc90000a08334 RSI: 0000000000000007 RDI: 00000000ec12f092 RBP: 00000000f30b4caa R08: 00000000768c8dd1 R09: 00000000763cbbc5 R10: 0000000000000014 R11: ffffffff81acff60 R12: 00000000000000b8 R13: ffff88804582fa00 R14: ffffc90000a082b0 R15: ffffc90000a08201 FS: 0000000000000000(0000) GS:ffff888125d3d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffdf747f20 CR3: 0000000027580000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x4f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204 __skb_ext_alloc net/core/skbuff.c:6977 [inline] skb_ext_add+0x148/0x8f0 net/core/skbuff.c:7080 nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline] br_nf_pre_routing_ipv6+0x132/0x6b0 net/bridge/br_netfilter_ipv6.c:172 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0x97f/0x14c0 net/bridge/br_input.c:434 __netif_receive_skb_core+0x10e1/0x4180 net/core/dev.c:5863 __netif_receive_skb_one_core net/core/dev.c:5975 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6090 process_backlog+0x60e/0x14f0 net/core/dev.c:6442 __napi_poll+0xc7/0x480 net/core/dev.c:7455 napi_poll net/core/dev.c:7519 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7646 handle_softirqs+0x286/0x870 kernel/softirq.c:579 do_softirq+0xec/0x180 kernel/softirq.c:480 __local_bh_enable_ip+0x17d/0x1c0 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+0x4d1/0x9e0 net/batman-adv/translation-table.c:3510 process_one_work kernel/workqueue.c:3239 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245