rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=7f74/1/0x4000000000000000 softirq=20708/20709 fqs=4351 rcu: hardirqs softirqs csw/system rcu: number: 1345833 0 0 rcu: cputime: 17591 34898 68 ==> 52490(ms) rcu: (t=10500 jiffies g=23013 q=1276 ncpus=2) CPU: 1 PID: 8076 Comm: syz.1.546 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg+0x39/0x240 arch/x86/kernel/unwind_orc.c:403 Code: 89 54 24 20 48 89 34 24 49 89 ff 48 bd 00 00 00 00 00 fc ff df e8 27 b1 4b 00 49 8d 5f 08 48 89 d8 48 c1 e8 03 48 89 44 24 10 <80> 3c 28 00 74 08 48 89 df e8 19 da a3 00 48 89 5c 24 18 4d 8b 77 RSP: 0018:ffffc900001efef0 EFLAGS: 00000a06 RAX: 1ffff9200003e012 RBX: ffffc900001f0090 RCX: ffff8880252b3c00 RDX: 0000000000000100 RSI: ffffc900001f0110 RDI: ffffc900001f0088 RBP: dffffc0000000000 R08: ffff8880252b3c00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900001f0088 R13: dffffc0000000000 R14: ffffffff8f0c82c2 R15: ffffc900001f0088 FS: 00007fa6225886c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000000 CR3: 0000000078fc6000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x1789/0x2970 arch/x86/kernel/unwind_orc.c:648 __unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 refdst_drop include/net/dst.h:270 [inline] skb_dst_drop include/net/dst.h:282 [inline] __dev_queue_xmit+0x983/0x36b0 net/core/dev.c:4393 neigh_output include/net/neighbour.h:543 [inline] ip6_finish_output2+0xe3d/0x1630 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+0xc26/0x14f0 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x2d5/0x630 net/ipv6/addrconf.c:4024 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x542/0x800 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 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+0xd3/0x190 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ba 9c da f6 48 89 df e8 72 71 db f6 e8 1d 7d ff f6 fb bf 01 00 00 00 92 78 ce f6 65 8b 05 63 af 75 75 85 c0 74 02 5b c3 e8 e0 96 72 RSP: 0018:ffffc900120bfab0 EFLAGS: 00000282 RAX: e229d3d789156900 RBX: ffff8880594165c0 RCX: e229d3d789156900 RDX: dffffc0000000000 RSI: ffffffff8acac900 RDI: 0000000000000001 RBP: ffffc900120bfc28 R08: ffffffff8e8addaf R09: 1ffffffff1d15bb5 R10: dffffc0000000000 R11: fffffbfff1d15bb6 R12: dffffc0000000000 R13: ffff88802e142880 R14: 1ffff11004a568a3 R15: 0000000000000004 spin_unlock_irq include/linux/spinlock.h:401 [inline] synchronize_group_exit kernel/exit.c:808 [inline] do_exit+0x252/0x2460 kernel/exit.c:818 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa62179bf79 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:00007fa622588028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000004 RBX: 00007fa621a16090 RCX: 00007fa62179bf79 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007fa6218327e0 R08: 0000000000000002 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa621a16128 R14: 00007fa621a16090 R15: 00007ffcf266aed8