syzbot

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10285 ticks this GP) idle=1dc4/1/0x4000000000000000 softirq=17070/17080 fqs=4454
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1232355          0            0
rcu: 	cputime:    17250      35229           43   ==> 52480(ms)
rcu: 	(t=10500 jiffies g=17757 q=1987 ncpus=2)
CPU: 0 PID: 7505 Comm: syz.0.537 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:get_stack_info_noinstr+0x1b/0x130 arch/x86/kernel/dumpstack_64.c:-1
Code: 7c 89 95 75 00 eb 9b cc cc cc cc cc cc cc cc 66 0f 1f 00 41 57 41 56 41 55 41 54 53 49 89 d6 49 89 f4 49 89 ff e8 15 01 00 00 <b3> 01 84 c0 0f 85 d0 00 00 00 65 48 8b 05 23 89 95 75 49 39 c4 74
RSP: 0018:ffffc90000006cf8 EFLAGS: 00000297
RAX: ffffffff812ec600 RBX: ffffc90000006dc8 RCX: ffffc900037c0000
RDX: ffffc90000006dc8 RSI: ffffc900037c8000 RDI: ffffc90000006d60
RBP: dffffc0000000000 R08: ffffc90000006e00 R09: 0000000000000000
R10: ffffc90000006dc8 R11: fffff52000000dc5 R12: ffff88804acb5a00
R13: ffffc90000006de8 R14: ffffc90000006dc8 R15: ffffc90000006d60
FS:  00007fc6f75f66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 000000005c966000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 get_stack_info+0x40/0x170 arch/x86/kernel/dumpstack_64.c:199
 __unwind_start+0x48b/0x7e0 arch/x86/kernel/unwind_orc.c:729
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1811 [inline]
 slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837
 slab_free mm/slub.c:3830 [inline]
 kmem_cache_free+0xf8/0x280 mm/slub.c:3852
 skb_kfree_head net/core/skbuff.c:943 [inline]
 skb_free_head net/core/skbuff.c:957 [inline]
 skb_release_data+0x60a/0x800 net/core/skbuff.c:987
 skb_release_all net/core/skbuff.c:1053 [inline]
 __kfree_skb net/core/skbuff.c:1067 [inline]
 kfree_skb_reason+0x10e/0x170 net/core/skbuff.c:1103
 kfree_skb include/linux/skbuff.h:1232 [inline]
 ipip6_tunnel_xmit net/ipv6/sit.c:1041 [inline]
 sit_tunnel_xmit+0xd56/0x1f70 net/ipv6/sit.c:1076
 __netdev_start_xmit include/linux/netdevice.h:4943 [inline]
 netdev_start_xmit include/linux/netdevice.h:4957 [inline]
 xmit_one net/core/dev.c:3619 [inline]
 dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3635
 __dev_queue_xmit+0x1a64/0x35a0 net/core/dev.c:4425
 neigh_output include/net/neighbour.h:543 [inline]
 ip6_finish_output2+0xe2e/0x1650 net/ipv6/ip6_output.c:141
 dst_output include/net/dst.h:467 [inline]
 NF_HOOK include/linux/netfilter.h:304 [inline]
 ndisc_send_skb+0xbed/0x14b0 net/ipv6/ndisc.c:513
 addrconf_rs_timer+0x2bc/0x600 net/ipv6/addrconf.c:4006
 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022
 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:preempt_schedule_irq+0xb0/0x140 kernel/sched/core.c:7009
Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 63 bf 01 00 00 00 e8 8b ca e4 f6 e8 56 4d 15 f7 fb bf 01 00 00 00 <e8> db b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0018:ffffc900037c7da0 EFLAGS: 00000286
RAX: 8132a200121e8300 RBX: 0000000000000000 RCX: 8132a200121e8300
RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: 0000000000000001
RBP: ffffc900037c7e40 R08: ffffffff8e4a836f R09: 1ffffffff1c9506d
R10: dffffc0000000000 R11: fffffbfff1c9506e R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920006f8fb4
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__syscall_enter_from_user_work kernel/entry/common.c:97 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2e/0x80 kernel/entry/common.c:118
Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 e9 fa ff ff 66 90 66 90 e8 10 8e 1d f7 e8 cb 8d 1d f7 fb 65 48 8b 05 72 57 95 75 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 dd 1f 04 f7 48
RSP: 0018:ffffc900037c7f08 EFLAGS: 00000286
RAX: ffff88804acb5a00 RBX: 00000000000000ca RCX: 8132a200121e8300
RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: ffffffff8afc63c0
RBP: ffffc900037c7f48 R08: ffffffff8e4a836f R09: 1ffffffff1c9506d
R10: dffffc0000000000 R11: fffffbfff1c9506e R12: 0000000000000000
R13: 0000000000000000 R14: ffffc900037c7f58 R15: 0000000000000000
 do_syscall_64+0x28/0xb0 arch/x86/entry/common.c:77
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc6f938eec9
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:00007fc6f75f60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fc6f95e5fa8 RCX: 00007fc6f938eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc6f95e5fa8
RBP: 00007fc6f95e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc6f95e6038 R14: 00007ffeeb3047d0 R15: 00007ffeeb3048b8
 </TASK>