rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10500 ticks this GP) idle=c2d/1/0x4000000000000000 softirq=16798/16798 fqs=4509 (t=10500 jiffies g=23121 q=1460) NMI backtrace for cpu 0 CPU: 0 PID: 7504 Comm: syz.6.833 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:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline] RIP: 0010:trace_kmalloc_node include/trace/events/kmem.h:100 [inline] RIP: 0010:__kmalloc_node_track_caller+0x15f/0x3a0 mm/slub.c:4966 Code: eb 02 b0 01 48 8b 74 24 18 44 0f b6 c8 4c 8d 44 24 20 b9 01 00 00 00 4c 89 ef 89 ea e8 0a d2 ff ff 48 8b 5c 24 20 45 8b 47 18 <0f> 1f 44 00 00 65 8b 05 5d 5f 46 7e 83 f8 08 0f 83 23 01 00 00 89 RSP: 0018:ffffc90000007960 EFLAGS: 00000286 RAX: ffff88805fc47800 RBX: ffff88805fc47800 RCX: 0000000000000000 RDX: 0000000000000200 RSI: 0000000000000000 RDI: ffff88805fc47a00 RBP: 0000000000082a20 R08: 0000000000000400 R09: ffff88805fc47800 R10: 00000000fbfa159f R11: 0000000091ce174f R12: ffff88805fc47800 R13: ffff888016841c80 R14: 0000000000000200 R15: ffff888016841c80 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] ndisc_alloc_skb+0xa6/0x420 net/ipv6/ndisc.c:422 ndisc_send_rs+0x291/0x730 net/ipv6/ndisc.c:691 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_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9d/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 be 9a d2 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 d6 22 a6 f7 65 8b 05 67 20 57 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900032af3c0 EFLAGS: 00000206 RAX: c40d3264e2ba3300 RBX: 0000000000000a06 RCX: c40d3264e2ba3300 RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001 RBP: ffffc900032af458 R08: dffffc0000000000 R09: fffffbfff1ff543a R10: fffffbfff1ff543a R11: 1ffffffff1ff5439 R12: dffffc0000000000 R13: ffff88802be88000 R14: ffffffff96262988 R15: 1ffff92000655e78 __debug_check_no_obj_freed lib/debugobjects.c:982 [inline] debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1003 free_pages_prepare mm/page_alloc.c:1345 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x237/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 free_slab mm/slub.c:2020 [inline] discard_slab mm/slub.c:2026 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2512 put_cpu_partial+0x12d/0x190 mm/slub.c:2592 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 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+0x127/0x330 mm/slub.c:4408 kmalloc include/linux/slab.h:612 [inline] tomoyo_realpath_from_path+0x118/0x610 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x1d5/0x5d0 security/tomoyo/file.c:723 tomoyo_path_mkdir+0xa5/0xe0 security/tomoyo/tomoyo.c:166 security_path_mkdir+0xe0/0x130 security/security.c:1155 do_mkdirat+0x158/0x5a0 fs/namei.c:4093 __do_sys_mkdir fs/namei.c:4118 [inline] __se_sys_mkdir fs/namei.c:4116 [inline] __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4116 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: 0033:0x7f52e6ad5749 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:00007f52e4d3c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f52e6d2bfa0 RCX: 00007f52e6ad5749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000 RBP: 00007f52e6b59f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f52e6d2c038 R14: 00007f52e6d2bfa0 R15: 00007fff87f6cf98