INFO: task syz.1.2756:11824 blocked for more than 143 seconds. Not tainted 6.1.132-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2756 state:D stack:22648 pid:11824 ppid:4248 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 perf_pending_task_sync kernel/events/core.c:5033 [inline] _free_event+0x169/0x1090 kernel/events/core.c:5039 put_event kernel/events/core.c:5164 [inline] perf_event_release_kernel+0x873/0x900 kernel/events/core.c:5289 perf_release+0x37/0x40 kernel/events/core.c:5299 __fput+0x3f6/0x8d0 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:203 get_signal+0x15d0/0x17a0 kernel/signal.c:2648 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f451fb8d169 RSP: 002b:00007f4520a87fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f451fda5fa0 RCX: 00007f451fb8d169 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000 RBP: 00007f451fc0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f451fda5fa0 R15: 00007fff011b7368 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e910 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32f110 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 3 locks held by kworker/1:1/26: #0: ffff88814c9ddd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90000a1fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16e0 net/ipv6/addrconf.c:4134 1 lock held by khungtaskd/28: #0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 2 locks held by kworker/u4:4/56: 2 locks held by getty/4008: #0: ffff888031021098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198 3 locks held by kworker/u4:6/4280: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003ef7d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 2 locks held by kworker/1:6/10784: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003377d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 2 locks held by syz.0.3203/13102: #0: ffffffff8e543c50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x338/0x590 net/core/net_namespace.c:504 #1: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x281/0x770 net/ipv4/ip_tunnel.c:1117 1 lock held by syz.6.3205/13103: #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 2 locks held by syz.6.3205/13108: #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 #1: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.8.3209/13113: #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x4a9/0x2320 drivers/net/tun.c:3104 1 lock held by syz.7.3211/13118: #0: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.5.3212/13119: #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 1 lock held by syz.5.3212/13121: #0: ffffffff8e5507a8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x4f5/0xf70 net/core/dev_ioctl.c:587 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.132-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4331 Comm: kworker/0:8 Not tainted 6.1.132-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: rcu_gp wait_rcu_exp_gp RIP: 0010:__lock_is_held kernel/locking/lockdep.c:-1 [inline] RIP: 0010:lock_is_held_type+0xce/0x180 kernel/locking/lockdep.c:5705 Code: 85 c0 75 2a 48 ff c3 49 63 85 d8 0a 00 00 48 83 c5 28 48 39 c3 7c d8 eb 11 48 c7 c7 40 c7 1f 8d 48 89 de e8 84 7c bd f9 eb cb <31> ed eb 1f 41 83 fe ff 74 14 31 c0 f6 45 22 03 0f 95 c0 31 ed 44 RSP: 0018:ffffc90004047698 EFLAGS: 00000046 RAX: 0000000000000003 RBX: 0000000000000003 RCX: 0000000080000002 RDX: ffff8880251a1dc0 RSI: ffffffff8d32e6c0 RDI: ffff88802bb6e470 RBP: ffff88802bb6e498 R08: dffffc0000000000 R09: ffffed100576db29 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000046 R13: ffff88802bb6d940 R14: 00000000ffffffff R15: ffffffff8d32e6c0 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000077570000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x89/0x130 kernel/rcu/update.c:125 task_css_set include/linux/cgroup.h:496 [inline] task_dfl_cgroup include/linux/cgroup.h:565 [inline] task_psi_group+0x50/0x1a0 kernel/sched/psi.c:892 psi_account_irqtime+0x111/0x750 kernel/sched/psi.c:1018 __schedule+0x9c4/0x4570 kernel/sched/core.c:6555 schedule+0xbf/0x180 kernel/sched/core.c:6637 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 synchronize_rcu_expedited_wait_once kernel/rcu/tree_exp.h:580 [inline] synchronize_rcu_expedited_wait kernel/rcu/tree_exp.h:631 [inline] rcu_exp_wait_wake kernel/rcu/tree_exp.h:699 [inline] rcu_exp_sel_wait_wake+0x806/0x1d80 kernel/rcu/tree_exp.h:733 process_one_work+0x917/0x1260 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295