INFO: task syz.1.3685:14312 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.3685 state:D stack:23280 pid:14312 ppid: 12394 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127 _free_event+0x34/0xe30 kernel/events/core.c:5133 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x635/0x2110 kernel/exit.c:890 do_group_exit+0x12c/0x2f0 kernel/exit.c:1004 get_signal+0x7eb/0x12e0 kernel/signal.c:2909 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7c52164019 RSP: 002b:00007f7c503bc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: fffffffffffffff5 RBX: 00007f7c523ebfa0 RCX: 00007f7c52164019 RDX: 0000000000000048 RSI: 00002000000017c0 RDI: 0000000000000005 RBP: 00007f7c521fb00c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c523ec038 R14: 00007f7c523ebfa0 R15: 00007ffd0279a7c8 Showing all locks held in the system: 2 locks held by kworker/1:1/23: 1 lock held by khungtaskd/27: #0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:1/144: 5 locks held by kworker/u4:4/1285: #0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1 #1: ffffc90005187d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285 #2: ffffffff8d441550 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589 #3: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_delete_nets+0xd2/0x370 net/ipv4/ip_tunnel.c:1132 #4: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #4: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845 1 lock held by dhcpcd/3851: #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695 2 locks held by getty/3946: #0: ffff88802c8b2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158 2 locks held by kworker/1:3/4223: #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1 #1: ffffc900030ffd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285 3 locks held by kworker/u4:6/4310: #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1 #1: ffffc9000317fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285 #2: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 3 locks held by kworker/1:10/13072: #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1 #1: ffffc90002fefd00 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285 #2: ffff88801dfd2400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757 2 locks held by syz.4.3408/13461: #0: ffffffff8d441550 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x324/0x5b0 net/core/net_namespace.c:499 #1: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1279 2 locks held by syz.0.3690/14356: 1 lock held by syz-executor/14610: #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3443 7 locks held by syz-executor/14658: #0: ffff88802cbc6460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590 #1: ffff888020b53888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287 #2: ffff888147e78cb8 (kn->active#284){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1fd/0x500 fs/kernfs/file.c:288 #3: ffffffff8cd8aaa8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd3/0x3a0 drivers/net/netdevsim/bus.c:344 #4: ffff88801dfd3178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline] #4: ffff88801dfd3178 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1064 [inline] #4: ffff88801dfd3178 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa1/0x710 drivers/base/dd.c:1279 #5: ffff88801dfd2400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline] #5: ffff88801dfd2400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x109/0x230 drivers/net/netdevsim/dev.c:1561 #6: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x8dd/0xac0 net/core/dev.c:10722 1 lock held by syz-executor/14705: #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695 2 locks held by kworker/1:13/14732: #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1 #1: ffffc90003f4fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285 1 lock held by syz-executor/14740: #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: __rtnl_newlink net/core/rtnetlink.c:3488 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_newlink+0xa26/0x1920 net/core/rtnetlink.c:3586 1 lock held by syz-executor/14743: #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695 1 lock held by syz-executor/14748: #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: __rtnl_newlink net/core/rtnetlink.c:3488 [inline] #0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_newlink+0xa26/0x1920 net/core/rtnetlink.c:3586 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe1b/0xe60 kernel/hung_task.c:369 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14356 Comm: syz.0.3690 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:127 [inline] RIP: 0010:seqcount_lockdep_reader_access+0x16d/0x1d0 include/linux/seqlock.h:102 Code: 20 48 8b 5c 24 20 41 c6 04 06 f8 48 89 de 48 81 e6 00 02 00 00 31 ff e8 d1 08 10 00 48 81 e3 00 02 00 00 75 11 e8 e3 04 10 00 <4d> 85 e4 75 16 e8 d9 04 10 00 eb 15 e8 d2 04 10 00 e8 ad 1c 57 08 RSP: 0018:ffffc90000007da0 EFLAGS: 00000006 RAX: ffffffff8168f7cd RBX: 0000000000000000 RCX: ffff8880219c1dc0 RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007e48 R08: ffffffff8d8b0def R09: 1ffffffff1b161bd R10: dffffc0000000000 R11: fffffbfff1b161be R12: 0000000000000000 R13: dffffc0000000000 R14: 1ffff92000000fb4 R15: dffffc0000000000 FS: 00007f71587226c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055658e742550 CR3: 0000000043319000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get+0x7b/0x270 kernel/time/timekeeping.c:831 clockevents_program_event+0xe2/0x310 kernel/time/clockevents.c:326 hrtimer_interrupt+0x4cb/0x8b0 kernel/time/hrtimer.c:1824 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_acquire+0x208/0x400 kernel/locking/lockdep.c:5627 Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f1 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04 RSP: 0018:ffffc9000322f640 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 08fac1ee8e4c1a00 RDX: 0000000000000000 RSI: ffffffff8a2b3e80 RDI: ffffffff8a7a4200 RBP: ffffc9000322f760 R08: dffffc0000000000 R09: 1ffffffff203dc18 R10: dffffc0000000000 R11: fffffbfff203dc19 R12: ffffffff8c31ef60 R13: 1ffff92000645ed4 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] inet_twsk_purge+0x10d/0x820 net/ipv4/inet_timewait_sock.c:268 ops_exit_list net/core/net_namespace.c:177 [inline] setup_net+0x842/0xa10 net/core/net_namespace.c:365 copy_net_ns+0x33e/0x5b0 net/core/net_namespace.c:503 create_new_namespaces+0x3ce/0x700 kernel/nsproxy.c:110 copy_namespaces+0x378/0x3d0 kernel/nsproxy.c:178 copy_process+0x1844/0x3ec0 kernel/fork.c:2294 kernel_clone+0x23f/0x990 kernel/fork.c:2681 __do_sys_clone kernel/fork.c:2798 [inline] __se_sys_clone kernel/fork.c:2782 [inline] __x64_sys_clone+0x19a/0x210 kernel/fork.c:2782 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f715a4ca019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7158721fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f715a751fa0 RCX: 00007f715a4ca019 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000041200000 RBP: 00007f715a56100c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f715a752038 R14: 00007f715a751fa0 R15: 00007ffe9c579c38