rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=b35/1/0x4000000000000000 softirq=15463/15464 fqs=181 (t=10501 jiffies g=19837 q=1034) NMI backtrace for cpu 0 CPU: 0 PID: 5905 Comm: syz.7.163 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x22d/0x380 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x31f/0x5f0 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x6ec/0x1120 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:2021 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811 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+0x4d/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:ffffc90000007060 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 36e9ea6eb976ea00 RDX: 0000000000000000 RSI: ffffffff8a2b3e80 RDI: ffffffff8a79c980 RBP: ffffc90000007180 R08: dffffc0000000000 R09: 1ffffffff2039618 R10: dffffc0000000000 R11: fffffbfff2039619 R12: ffffffff8c31ef20 R13: 1ffff92000000e18 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] is_bpf_text_address+0x1d/0x270 kernel/bpf/core.c:725 kernel_text_address kernel/extable.c:151 [inline] __kernel_text_address+0x9a/0x100 kernel/extable.c:105 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] nlmsg_new include/net/netlink.h:964 [inline] __neigh_notify+0x142/0x2e0 net/core/neighbour.c:3379 neigh_cleanup_and_release+0x9d/0x250 net/core/neighbour.c:101 neigh_del net/core/neighbour.c:197 [inline] neigh_remove_one+0x4e0/0x5e0 net/core/neighbour.c:218 neigh_forced_gc net/core/neighbour.c:251 [inline] neigh_alloc net/core/neighbour.c:429 [inline] ___neigh_create+0x48f/0x2210 net/core/neighbour.c:591 ip6_finish_output2+0x9f5/0x1530 net/ipv6/ip6_output.c:127 dst_output include/net/dst.h:452 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] ndisc_send_skb+0xb7a/0x1410 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x367/0x640 net/ipv6/addrconf.c:3959 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x56c/0x810 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__read_once_word_nocheck+0x3/0x10 include/asm-generic/rwonce.h:67 Code: 44 89 e1 80 e1 07 38 c1 0f 8c 1c fd ff ff 4c 89 e7 e8 61 e0 88 00 e9 0f fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8b 07 00 00 cc cc 00 00 cc cc 00 00 cc cc 31 c0 81 ff 03 00 00 40 0f RSP: 0018:ffffc9000331f3c8 EFLAGS: 00000202 RAX: ffffffff89b99f2c RBX: ffffc9000331f468 RCX: 1ffff92000663e01 RDX: ffffc9000331ff20 RSI: ffffffff8d986470 RDI: ffffc9000331ff18 RBP: ffffc90003318000 R08: 0000000000000001 R09: 0000000000000009 R10: dffffc0000000000 R11: fffff52000663e99 R12: 1ffffffff1c07941 R13: 1ffffffff1c07941 R14: ffffc90003320000 R15: ffffc9000331ff18 deref_stack_reg arch/x86/kernel/unwind_orc.c:360 [inline] unwind_next_frame+0x970/0x1cf0 arch/x86/kernel/unwind_orc.c:539 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] tc_action_net_init include/net/act_api.h:140 [inline] tunnel_key_init_net+0x61/0x190 net/sched/act_tunnel_key.c:806 ops_init+0x360/0x5f0 net/core/net_namespace.c:138 setup_net+0x39e/0xa10 net/core/net_namespace.c:333 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: 0033:0x7f0ee9f14e59 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:00007f0ee814cfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f0eea18e090 RCX: 00007f0ee9f14e59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000c0000000 RBP: 00007f0ee9faae6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f0eea18e128 R14: 00007f0eea18e090 R15: 00007ffffd3dba38