INFO: task syz.0.4610:26152 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.4610 state:D stack:27224 pid:26152 tgid:26151 ppid:19021 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7f7/0x1550 kernel/locking/mutex.c:820 nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1948 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2556 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752 __sys_sendmsg net/socket.c:2784 [inline] __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787 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: 0033:0x7ff17b19ce59 RSP: 002b:00007ff17c132028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ff17b415fa0 RCX: 00007ff17b19ce59 RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000005 RBP: 00007ff17b232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff17b416038 R14: 00007ff17b415fa0 R15: 00007ffd8f972778 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e95cc20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e95cc20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e95cc20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5387: #0: ffff888036be60a0 (&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+0x45c/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz.1.3265/20117: #0: ffffffff8fe3a248 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8ec8b2c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1948 2 locks held by syz.0.4610/26152: #0: ffffffff8fe3a248 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8ec8b2c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1948 3 locks held by syz.5.6048/32076: #0: ffffffff8fdbafe8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:575 #1: ffffffff8fdc9d00 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline] #1: ffffffff8fdc9d00 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940 net/core/net_namespace.c:248 #2: ffffffff8e962f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #2: ffffffff8e962f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.3.6049/32090: 7 locks held by syz.6.6050/32088: #0: ffff88804eab6af8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_register_user+0x35/0x1d0 net/bluetooth/l2cap_core.c:1714 #1: ffffffff8ff7a4e8 (hidp_session_sem){++++}-{4:4}, at: hidp_session_probe+0x98/0x890 net/bluetooth/hidp/core.c:1142 #2: ffffffff8f843e60 (input_mutex){+.+.}-{4:4}, at: class_mutex_intr_constructor include/linux/mutex.h:255 [inline] #2: ffffffff8f843e60 (input_mutex){+.+.}-{4:4}, at: input_register_device+0xa56/0x1140 drivers/input/input.c:2391 #3: ffff888029bd65c0 (&led_cdev->led_access){+.+.}-{4:4}, at: led_classdev_register_ext+0x484/0x9c0 drivers/leds/led-class.c:539 #4: ffffffff8f1446e8 (triggers_list_lock){++++}-{4:4}, at: led_trigger_set_default+0x77/0x2a0 drivers/leds/led-triggers.c:297 #5: ffff888029bd64e0 (&led_cdev->trigger_lock){+.+.}-{4:4}, at: led_trigger_set_default+0x87/0x2a0 drivers/leds/led-triggers.c:298 #6: ffffffff8e962f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #6: ffffffff8e962f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.6.6050/32091: #0: ffffffff8ff7a4e8 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1040 1 lock held by syz.6.6050/32093: #0: ffffffff8ff7a4e8 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1040 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 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+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x389/0x470 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 48 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:debug_object_deactivate+0x67/0x3a0 lib/debugobjects.c:900 Code: 46 86 c8 61 48 0f af c8 48 c1 e9 2f 83 e1 f8 4c 8d 2c c9 49 81 c5 e0 33 63 9a 48 8d 3c c9 48 81 c7 e8 33 63 9a 48 89 7c 24 18 a4 e6 ef 06 48 89 44 24 10 4c 89 e8 48 c1 e8 03 42 80 3c 30 00 RSP: 0018:ffffc90000a08ce0 EFLAGS: 00000082 RAX: 000ffff8880251c2 RBX: ffff8880b8726140 RCX: 0000000000008cc0 RDX: 0000000000000100 RSI: ffffffff8bcf39c0 RDI: ffffffff9a6826a8 RBP: ffffc90000a08ef8 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520001411a0 R12: dffffc0000000000 R13: ffffffff9a6826a0 R14: dffffc0000000000 R15: ffff8880251c25f8 FS: 0000000000000000(0000) GS:ffff88812538b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000328030 CR3: 000000000e74a000 CR4: 00000000003526f0 Call Trace: debug_timer_deactivate kernel/time/timer.c:798 [inline] debug_deactivate kernel/time/timer.c:842 [inline] detach_timer+0x33/0x2d0 kernel/time/timer.c:889 expire_timers kernel/time/timer.c:1782 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x5d3/0x8b0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 eb 85 86 f5 cc RSP: 0018:ffffc90000b876f8 EFLAGS: 00000293 RAX: ffffffff81b9b376 RBX: ffff8880b873c388 RCX: ffff888020ab0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000b87840 R08: ffffffff90309df7 R09: 1ffffffff20613be R10: dffffc0000000000 R11: fffffbfff20613bf R12: 1ffff110170c85d1 R13: dffffc0000000000 R14: ffff8880b8642e88 R15: 0000000000000000 csd_lock_wait kernel/smp.c:342 [inline] smp_call_function_many_cond+0xfe6/0x13d0 kernel/smp.c:892 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057 on_each_cpu include/linux/smp.h:72 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline] smp_text_poke_batch_finish+0xb5f/0x1160 arch/x86/kernel/alternative.c:3045 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:913 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 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