INFO: task syz.7.2510:17005 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.7.2510      state:D stack:28808 pid:17005 tgid:17001 ppid:15835  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 cgroup_lock_and_drain_offline+0x51a/0x650 kernel/cgroup/cgroup.c:3275
 cgroup1_get_tree+0x9d/0x890 kernel/cgroup/cgroup-v1.c:1265
 vfs_get_tree+0x92/0x2a0 fs/super.c:1700
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3765 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3841
 do_mount fs/namespace.c:4174 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4367
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2a0939e0d9
RSP: 002b:00007f2a0a208028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f2a09626090 RCX: 00007f2a0939e0d9
RDX: 0000200000000640 RSI: 0000200000000600 RDI: 0000000000000000
RBP: 00007f2a09435024 R08: 00002000000003c0 R09: 0000000000000000
R10: 0000000002208000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2a09626128 R14: 00007f2a09626090 R15: 00007fff73d99e68
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/10:
3 locks held by kworker/u8:1/13:
 #0: ffff888032267140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff888032267140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc90000127c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc90000127c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffffffff90027b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff90027b40 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x116/0x15c0 net/ipv6/addrconf.c:4229
1 lock held by khungtaskd/31:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
8 locks held by kworker/u8:3/48:
 #0: ffff88801c28e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88801c28e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc90000b87c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc90000b87c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffffffff90018f88 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:673
 #3: ffff88802bf18128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
 #3: ffff88802bf18128 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline]
 #3: ffff88802bf18128 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:557
 #4: ffff88802bf1f258 (&devlink->lock_key#15){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline]
 #4: ffff88802bf1f258 (&devlink->lock_key#15){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline]
 #4: ffff88802bf1f258 (&devlink->lock_key#15){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:557
 #5: ffffffff90027b40 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x173/0x800 drivers/net/netdevsim/netdev.c:1191
 #6: ffff888088098e70 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2849 [inline]
 #6: ffff888088098e70 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x5bb/0x2140 net/core/dev.c:12407
 #7: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #7: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
3 locks held by kworker/0:2/187:
 #0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc900030bfc40 (netdev_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc900030bfc40 (netdev_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffffffff90027b40 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x6f/0x770 net/core/netdev_work.c:132
2 locks held by getty/5365:
 #0: ffff888032afe0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/6892:
 #0: ffff88804e2acea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:497 [inline]
 #0: ffff88804e2acea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0 net/bluetooth/hci_core.c:2678
5 locks held by syz-executor/17221:
 #0: ffff888074958ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:497 [inline]
 #0: ffff888074958ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0 net/bluetooth/hci_core.c:2678
 #1: ffff8880749580b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x61f/0x10a0 net/bluetooth/hci_sync.c:5501
 #2: ffffffff901afc80 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
 #2: ffffffff901afc80 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0x99/0x260 net/bluetooth/hci_conn.c:2735
 #3: ffff88804d90faf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x9f/0x520 net/bluetooth/l2cap_core.c:1808
 #4: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #4: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz.5.2720/18047:
 #0: ffff88807f91a0f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
 #1: ffff888033b0c450 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
 #1: ffff888033b0c450 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
 #2: ffff8880765a6880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d8/0x540 fs/kernfs/file.c:336
3 locks held by dhcpcd-run-hook/18234:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8012 Comm: ipvs-e:10:0 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:debug_spin_lock_after kernel/locking/spinlock_debug.c:94 [inline]
RIP: 0010:do_raw_spin_lock+0x15c/0x2f0 kernel/locking/spinlock_debug.c:118
Code: 00 00 f0 0f b1 0b 0f 85 20 01 00 00 43 c6 44 34 04 f8 65 8b 1d 19 57 c9 11 43 0f b6 04 37 84 c0 0f 85 6a 01 00 00 41 89 5d 00 <48> 8b 44 24 10 42 80 3c 30 00 48 8b 5c 24 18 74 12 48 89 df e8 6b
RSP: 0018:ffffc90000a08dc0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a08e00
RBP: ffffc90000a08e78 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520001411c0 R12: 1ffff920001411bc
R13: ffff8880b87281c8 R14: dffffc0000000000 R15: 1ffff110170e5039
FS:  0000000000000000(0000) GS:ffff888125055000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcd0efc9f8 CR3: 0000000035838000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock_irqsave+0x4c/0x60 kernel/locking/spinlock.c:166
 hrtimer_interrupt+0xf8/0x910 kernel/time/hrtimer.c:2197
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198
Code: f7 e8 2d 0d d0 f5 f7 c3 00 02 00 00 74 05 e8 00 ee fb f5 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> c4 20 c1 f5 65 8b 05 bd 60 99 07 85 c0 74 18 5b 41 5e e9 8c f1
RSP: 0018:ffffc9001f1b79c8 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000283 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8e2283d3 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffffffff90574437 R09: 1ffffffff20ae886
R10: dffffc0000000000 R11: fffffbfff20ae887 R12: ffff8880b8726040
R13: 0000000000000000 R14: ffff8880b8726040 R15: 0000000000000283
 __mod_timer+0xb53/0xed0 kernel/time/timer.c:1139
 schedule_timeout+0x14d/0x2c0 kernel/time/sleep_timeout.c:98
 ip_vs_estimation_kthread+0x29ef/0x3950 net/netfilter/ipvs/ip_vs_est.c:216
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>