rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=999c/1/0x4000000000000000 softirq=106401/106402 fqs=5246
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1394799          0            0
rcu: 	cputime:    17300      35179           69   ==> 52500(ms)
rcu: 	(t=10502 jiffies g=153865 q=779 ncpus=2)
CPU: 1 PID: 26210 Comm: syz.4.6903 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:deref_stack_reg+0x1a/0x240 arch/x86/kernel/unwind_orc.c:402
Code: 24 18 e9 c1 fe ff ff 66 0f 1f 84 00 00 00 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 28 48 89 54 24 20 48 89 34 24 49 89 ff <48> bd 00 00 00 00 00 fc ff df e8 37 b2 4b 00 49 8d 5f 08 48 89 d8
RSP: 0018:ffffc900001f0478 EFLAGS: 00000296
RAX: fffffffffffffff0 RBX: ffffffff8f1194d3 RCX: 0000000000000003
RDX: ffffc900001f05e8 RSI: ffffc900001f06d0 RDI: ffffc900001f05a8
RBP: ffffc900001f05f8 R08: ffff888021c90000 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900001f05a8
R13: dffffc0000000000 R14: ffffffff8f1194d2 R15: ffffc900001f05a8
FS:  00007f3d241ef6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30223ffc CR3: 0000000043d39000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 unwind_next_frame+0x1789/0x2970 arch/x86/kernel/unwind_orc.c:648
 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 kmem_cache_alloc_node+0x14c/0x320 mm/slub.c:3540
 __alloc_skb+0x103/0x2c0 net/core/skbuff.c:643
 alloc_skb include/linux/skbuff.h:1284 [inline]
 ndisc_alloc_skb+0xa6/0x450 net/ipv6/ndisc.c:423
 ndisc_send_rs+0x2a6/0x610 net/ipv6/ndisc.c:707
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:generic_exec_single+0x481/0x4f0 kernel/smp.c:418
Code: 75 11 e8 02 02 0b 00 48 85 db 75 16 e8 f8 01 0b 00 eb 15 e8 f1 01 0b 00 e8 bc 39 08 09 48 85 db 74 ea e8 e2 01 0b 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 43 c7 44 2c 08
RSP: 0018:ffffc9000ebe7a00 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000
RDX: ffffc9000d457000 RSI: 0000000000003b9e RDI: 0000000000003b9f
RBP: ffffc9000ebe7ad0 R08: ffffffff911bf5ff R09: 1ffffffff2237ebf
R10: dffffc0000000000 R11: fffffbfff2237ec0 R12: 1ffff92001d7cf44
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92001d7cf65
 smp_call_function_single+0x36d/0x5a0 kernel/smp.c:647
 task_function_call kernel/events/core.c:120 [inline]
 perf_install_in_context+0x5be/0x920 kernel/events/core.c:2948
 __do_sys_perf_event_open kernel/events/core.c:12915 [inline]
 __se_sys_perf_event_open+0x1836/0x1c50 kernel/events/core.c:12567
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3d2339aeb9
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:00007f3d241ef028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f3d23615fa0 RCX: 00007f3d2339aeb9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007f3d23408c1f R08: 0000000000000002 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3d23616038 R14: 00007f3d23615fa0 R15: 00007ffed15aa518
 </TASK>