INFO: task kworker/1:1:42 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/1:1 state:D stack:25928 pid:42 tgid:42 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0xfee/0x6120 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 class_wiphy_constructor include/net/cfg80211.h:6441 [inline] reg_leave_invalid_chans net/wireless/reg.c:2450 [inline] reg_check_chans_work+0x12f/0x11d0 net/wireless/reg.c:2465 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.0.3158:17553 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.3158 state:D stack:25624 pid:17553 tgid:17552 ppid:14359 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0xfee/0x6120 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 netdev_wait_allrefs_any net/core/dev.c:11609 [inline] netdev_run_todo+0xcd5/0x12c0 net/core/dev.c:11729 nsim_destroy+0x21a/0x830 drivers/net/netdevsim/netdev.c:1192 __nsim_dev_port_del+0x189/0x240 drivers/net/netdevsim/dev.c:1528 nsim_drv_port_del+0x118/0x180 drivers/net/netdevsim/dev.c:1835 del_port_store+0x129/0x170 drivers/net/netdevsim/bus.c:118 dev_attr_store+0x58/0x80 drivers/base/core.c:2437 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1070 fs/read_write.c:688 ksys_write+0x12a/0x250 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc9a1d9c819 RSP: 002b:00007fc9a2bd4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fc9a2015fa0 RCX: 00007fc9a1d9c819 RDX: 0000000000000001 RSI: 0000200000000380 RDI: 0000000000000006 RBP: 00007fc9a1e32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc9a2016038 R14: 00007fc9a2015fa0 R15: 00007ffde61f0cd8 Showing all locks held in the system: 2 locks held by kworker/0:0/9: 1 lock held by khungtaskd/30: #0: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 6 locks held by kworker/R-write/32: #0: ffff88801cad3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90000a87c70 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff8880370ba0e0 (&type->s_umount_key#33){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:565 #3: ffff8880370b8c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x278/0x600 mm/page-writeback.c:2575 #4: ffff888037376950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444 #5: ffff88807e5c1f38 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x45a/0xd30 fs/ext4/inode.c:818 4 locks held by kworker/1:1/42: #0: ffff88813fe61d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90000b27d08 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x11d0 net/wireless/reg.c:2462 #3: ffff888041658788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline] #3: ffff888041658788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2450 [inline] #3: ffff888041658788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x12f/0x11d0 net/wireless/reg.c:2465 3 locks held by kworker/R-ipv6_/3184: #0: ffff8880336b1148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc9000f7efc70 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4738 5 locks held by kworker/R-bat_e/3409: 4 locks held by kworker/R-ext4-/5157: 2 locks held by getty/5584: #0: ffff8880386d00a0 (&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+0x419/0x1500 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5812: #0: ffff888079a72088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 #1: ffff8880370ba518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3589 3 locks held by kworker/0:3/5819: #0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc900039e7d08 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/0:6/5945: 3 locks held by kworker/u10:0/7879: 3 locks held by kworker/u10:1/7882: 3 locks held by kworker/u10:2/7887: 3 locks held by kworker/u10:3/7940: 3 locks held by kworker/u10:4/7941: 3 locks held by kworker/u10:5/8268: 3 locks held by kworker/u10:6/9129: 3 locks held by kworker/u10:7/9676: 2 locks held by kworker/0:2/16701: 1 lock held by syz.2.3012/16989: #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436 1 lock held by syz.3.3155/17546: #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436 6 locks held by syz.0.3158/17553: #0: ffff88807c5d2478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1261 #1: ffff888035bee420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740 #2: ffff888082e78888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #3: ffff888037d15b48 (kn->active#204){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #3: ffff888037d15b48 (kn->active#204){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #4: ffff8880217eb250 (&devlink->lock_key#7){+.+.}-{4:4}, at: nsim_drv_port_del+0x4e/0x180 drivers/net/netdevsim/dev.c:1830 #5: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: netdev_wait_allrefs_any net/core/dev.c:11609 [inline] #5: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: netdev_run_todo+0xcd5/0x12c0 net/core/dev.c:11729 1 lock held by kworker/u10:8/17569: 1 lock held by syz-executor/17600: #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/17607: #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90617328 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 ============================================= 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 03/18/2026 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:436 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: 3409 Comm: kworker/R-bat_e Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: bat_events batadv_dat_purge RIP: 0010:__in6_dev_get include/net/addrconf.h:348 [inline] RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:449 [inline] RIP: 0010:find_match net/ipv6/route.c:780 [inline] RIP: 0010:__find_rr_leaf+0x186/0x1070 net/ipv6/route.c:868 Code: 0e 00 00 4c 8b b3 c8 00 00 00 49 8d be c0 00 00 00 48 89 f8 48 c1 e8 03 42 80 3c 38 00 0f 85 d5 0d 00 00 4d 8b b6 c0 00 00 00 35 80 55 01 31 ff 89 c6 89 44 24 38 e8 e8 1e cf f7 8b 44 24 38 RSP: 0018:ffffc900000074e8 EFLAGS: 00000246 RAX: 1ffff1100757e018 RBX: ffff888061b4b800 RCX: ffffffff8a391ee6 RDX: ffff8880341edb80 RSI: ffffffff8a391ef4 RDI: ffff88803abf00c0 RBP: ffff888061b4b864 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: ffff888061b4b8df R14: ffff888034e37000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124340000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2ecf6ff8 CR3: 000000000e598000 CR4: 00000000003526f0 Call Trace: find_rr_leaf net/ipv6/route.c:889 [inline] rt6_select net/ipv6/route.c:933 [inline] fib6_table_lookup+0x50f/0xa10 net/ipv6/route.c:2247 ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2283 pol_lookup_func include/net/ip6_fib.h:636 [inline] fib6_rule_lookup+0x52f/0x720 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2352 [inline] ip6_route_input+0x662/0xc50 net/ipv6/route.c:2655 ip6_rcv_finish_core.isra.0+0x1a9/0x5a0 net/ipv6/ip6_input.c:66 ip6_rcv_finish net/ipv6/ip6_input.c:77 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x1e8/0x3d0 net/ipv6/ip6_input.c:311 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6181 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6294 process_backlog+0x37a/0x1580 net/core/dev.c:6645 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7709 napi_poll net/core/dev.c:7772 [inline] net_rx_action+0xa40/0xf20 net/core/dev.c:7929 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 spin_unlock_bh include/linux/spinlock.h:395 [inline] __batadv_dat_purge.part.0+0x294/0x3c0 net/batman-adv/distributed-arp-table.c:185 __batadv_dat_purge net/batman-adv/distributed-arp-table.c:166 [inline] batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:204 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] rescuer_thread+0x905/0x14a0 kernel/workqueue.c:3583 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245