rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10487 ticks this GP) idle=ec5/1/0x4000000000000000 softirq=17172/17173 fqs=5244 (t=10501 jiffies g=23209 q=897) NMI backtrace for cpu 0 CPU: 0 PID: 7633 Comm: syz.2.905 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 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+0x22f/0x380 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x31d/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+0x6d8/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 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+0x4fe/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 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:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc900000077a0 EFLAGS: 00000206 RAX: a252a3b220a4dc00 RBX: 1ffff92000000ef8 RCX: a252a3b220a4dc00 RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800 RBP: ffffc90000007880 R08: dffffc0000000000 R09: fffffbfff1ff5439 R10: fffffbfff1ff5439 R11: 1ffffffff1ff5438 R12: ffffffff8c120c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] ndisc_send_skb+0xdc4/0x14a0 net/ipv6/ndisc.c:521 addrconf_rs_timer+0x2b8/0x600 net/ipv6/addrconf.c:3956 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x525/0x7c0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 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:preempt_schedule_irq+0xac/0x150 kernel/sched/core.c:6799 Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 70 bf 01 00 00 00 e8 af 44 a7 f7 e8 fa bd d3 f7 fb bf 01 00 00 00 ef b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc900031aee60 EFLAGS: 00000286 RAX: a252a3b220a4dc00 RBX: 0000000000000000 RCX: a252a3b220a4dc00 RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001 RBP: ffffc900031aef10 R08: dffffc0000000000 R09: fffffbfff1ff541a R10: fffffbfff1ff541a R11: 1ffffffff1ff5419 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000635dcc irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:_compound_head include/linux/page-flags.h:198 [inline] RIP: 0010:virt_to_head_page include/linux/mm.h:913 [inline] RIP: 0010:qlink_to_cache mm/kasan/quarantine.c:120 [inline] RIP: 0010:qlist_free_all+0x5a/0x90 mm/kasan/quarantine.c:173 Code: e8 db 03 00 00 4d 89 ef 4d 85 ed 74 2a 4c 89 f6 4d 85 f6 75 e5 4c 89 ff e8 53 27 79 ff 48 c1 e8 06 48 83 e0 c0 4a 8b 4c 20 08 c1 01 74 c4 48 ff c9 48 89 c8 eb bf 48 c7 43 08 00 00 00 00 48 RSP: 0018:ffffc900031aefd0 EFLAGS: 00000202 RAX: 0000000001e85680 RBX: ffffc900031af000 RCX: ffffea0001e85601 RDX: ffffc900101f0000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc900031af258 R08: ffff88805fe1c000 R09: 000000000010000d R10: fffffbfff1ff541a R11: 1ffffffff1ff5419 R12: ffffea0000000000 R13: ffff88807a15ac00 R14: 0000000000000000 R15: ffff88807a15ac00 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] __kmalloc_track_caller+0x125/0x330 mm/slub.c:4930 kstrdup mm/util.c:60 [inline] kstrdup_const+0x51/0x90 mm/util.c:83 kobject_set_name_vargs+0x5d/0x110 lib/kobject.c:297 dev_set_name+0xd1/0x120 drivers/base/core.c:3200 netdev_register_kobject+0xaf/0x310 net/core/net-sysfs.c:1995 register_netdevice+0x1019/0x16b0 net/core/dev.c:10397 __ip_tunnel_create+0x2bf/0x380 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x232/0x6b0 net/ipv4/ip_tunnel.c:1084 ops_init+0x357/0x600 net/core/net_namespace.c:138 setup_net+0x38d/0x9f0 net/core/net_namespace.c:333 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178 copy_process+0x180f/0x3e00 kernel/fork.c:2293 kernel_clone+0x219/0x930 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780 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: 0033:0x7f01af6f5749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f01ad93afe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f01af94c090 RCX: 00007f01af6f5749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000061000600 RBP: 00007f01af779f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f01af94c128 R14: 00007f01af94c090 R15: 00007fff48815328