INFO: task syz.0.572:6177 blocked for more than 143 seconds. Not tainted 6.1.134-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.572 state:D stack:21816 pid:6177 ppid:4253 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+0xb3/0x12a0 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+0x47/0x80 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff148d8e169 RSP: 002b:00007ff149b73fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007ff148fb5fa0 RCX: 00007ff148d8e169 RDX: 0000200000000400 RSI: 00002000000006c0 RDI: 0000000048000200 RBP: 00007ff148e10a68 R08: 0000200000000700 R09: 0000200000000700 R10: 0000200000000440 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff148fb5fa0 R15: 00007fffe5f23e48 Showing all locks held in the system: 3 locks held by kworker/u4:1/11: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90000107d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 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: ffff88814ca60938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90000a1fd20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4675 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 getty/4005: #0: ffff888030ade098 (&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 1 lock held by syz-executor/4239: 2 locks held by syz.2.1355/8561: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e550d68 (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.3.1356/8562: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 1 lock held by syz.4.1363/8579: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x136/0x6d0 net/netlink/af_netlink.c:2287 1 lock held by syz.5.1361/8583: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x136/0x6d0 net/netlink/af_netlink.c:2287 1 lock held by syz.1.1364/8587: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x4a9/0x2320 drivers/net/tun.c:3104 1 lock held by syz.1.1364/8589: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x4a9/0x2320 drivers/net/tun.c:3104 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.134-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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4239 Comm: syz-executor Not tainted 6.1.134-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:ct_dynticks_nmi_nesting include/linux/context_tracking_state.h:92 [inline] RIP: 0010:ct_nmi_exit+0x133/0x1c0 kernel/context_tracking.c:224 Code: 89 c3 83 f8 08 0f 83 89 00 00 00 48 8b 1c dd 70 89 df 8c 48 8d bb a8 56 03 00 be 04 00 00 00 e8 73 cb 30 f7 8b 83 a8 56 03 00 <48> c7 c7 40 05 15 8b e8 61 0a 00 00 65 48 8b 05 71 74 52 75 48 83 RSP: 0018:ffffc90003ad7de8 EFLAGS: 00000056 RAX: 000000000007cc34 RBX: ffff8880b8f00000 RCX: ffffffff8ab0e22d RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b8f356a8 RBP: ffffc90003ad7eb8 R08: dffffc0000000000 R09: ffffed10171e6ad6 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 1ffff9200075afc0 R14: ffff8880b8f356a0 R15: dffffc0000000000 FS: 0000555590c2d500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555953e55c8 CR3: 000000002fc11000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: ct_irq_exit_irqson+0xda/0x1b0 kernel/context_tracking.c:422 trace_irq_disable_rcuidle+0xda/0x140 include/trace/events/preemptirq.h:36 local_irq_disable_exit_to_user include/linux/entry-common.h:191 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x58/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0x80 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f133338cb3d Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b5 e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d 01 7a 1f 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec RSP: 002b:00007ffc5504b048 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f133338cb3d RDX: 0000000000000004 RSI: 00007ffc5504b05c RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffc551620b0 R09: 0000000000000010 R10: 00007ffc55162080 R11: 0000000000000246 R12: 00007ffc5504b470 R13: 0000000000000004 R14: 00007ffc5504b05c R15: 00007ffc5504b0f0