INFO: task syz.9.949:10907 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.949 state:D stack:25832 pid:10907 ppid:7298 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 perf_pending_task_sync kernel/events/core.c:5236 [inline] _free_event+0x176/0xfb0 kernel/events/core.c:5242 put_event kernel/events/core.c:5370 [inline] perf_event_release_kernel+0x7c8/0x850 kernel/events/core.c:5495 perf_release+0x3b/0x40 kernel/events/core.c:5505 __fput+0x221/0x940 fs/file_table.c:418 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x986/0x2530 kernel/exit.c:884 do_group_exit+0x22d/0x2f0 kernel/exit.c:1026 get_signal+0x12a6/0x1390 kernel/signal.c:2903 arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f417339de99 RSP: 002b:00007f41741a10e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f4173625fa8 RCX: 00007f417339de99 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4173625fa8 RBP: 00007f4173625fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4173626038 R14: 00007ffe86bd2990 R15: 00007ffe86bd2a78 Showing all locks held in the system: 3 locks held by kworker/u4:0/11: #0: ffff88802c943538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff88802c943538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #2: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xce/0x1550 net/ipv6/addrconf.c:4181 1 lock held by khungtaskd/28: #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 3 locks held by kworker/u4:10/4726: #0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc9000ef57d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000ef57d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #2: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286 2 locks held by dhcpcd/5433: #0: ffff888018af2690 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf4/0x7a0 net/netlink/af_netlink.c:2341 #1: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x77c/0xec0 net/netlink/af_netlink.c:2268 2 locks held by getty/5531: #0: ffff88802d1f40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217 2 locks held by kworker/0:3/5763: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc9000452fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000452fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 2 locks held by kworker/u4:14/12145: #0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559 #1: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #1: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #1: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9952 [inline] #1: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x19e/0x730 kernel/events/core.c:9990 2 locks held by syz.2.1387/13453: #0: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3514 #1: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #1: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004 1 lock held by syz.6.1389/13471: #0: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x83c/0x1140 net/core/dev_ioctl.c:794 1 lock held by syz.1.1392/13490: #0: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3f7/0x2070 drivers/net/tun.c:3124 1 lock held by syz.1.1392/13491: #0: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3f7/0x2070 drivers/net/tun.c:3124 1 lock held by syz.0.1394/13498: #0: ffffffff8e3d5b08 (rtnl_mutex){+.+.}-{3:3}, at: bpf_map_offload_map_alloc+0x135/0x610 kernel/bpf/offload.c:525 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf59/0xfa0 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 172 Comm: kworker/0:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 Workqueue: 0x0 (events_freezable) RIP: 0010:debug_object_deactivate+0x108/0x380 lib/debugobjects.c:806 Code: be bd 05 00 00 00 44 3b 25 1d 67 54 0a 7e 07 44 89 25 14 67 54 0a 48 8b 7c 24 10 48 8b 74 24 08 4c 8b 64 24 18 e9 cf 00 00 00 <4d> 8d 65 10 4d 89 e7 49 c1 ef 03 41 0f b6 04 1f 84 c0 0f 85 b0 01 RSP: 0018:ffffc90002d57b68 EFLAGS: 00000046 RAX: 1ffff1100f16871f RBX: dffffc0000000000 RCX: 0000000000000001 RDX: ffffffff9757fd18 RSI: 0000000000000004 RDI: ffffc90002d57a40 RBP: 1ffff1100f231e5e R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520005aaf48 R12: 0000000000000001 R13: ffff88807918f2d8 R14: ffff88807918f2f0 R15: ffff88805f4c0550 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005599061de660 CR3: 000000000cf32000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: debug_work_deactivate kernel/workqueue.c:580 [inline] process_one_work kernel/workqueue.c:2581 [inline] process_scheduled_works+0x350/0x1600 kernel/workqueue.c:2730 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293