rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=e90c/1/0x4000000000000000 softirq=35269/35270 fqs=5249 rcu: hardirqs softirqs csw/system rcu: number: 1310816 0 0 rcu: cputime: 18505 33983 71 ==> 52520(ms) rcu: (t=10503 jiffies g=49677 q=1043 ncpus=2) CPU: 1 PID: 12022 Comm: syz.1.1729 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_cmp8+0x2e/0x80 kernel/kcov.c:293 Code: 48 8b 04 24 65 48 8b 0d e0 22 7e 7e 65 8b 15 e1 22 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00 00 <74> 4e 8b 91 f8 15 00 00 83 fa 03 75 43 48 8b 91 00 16 00 00 44 8b RSP: 0018:ffffc900001f0310 EFLAGS: 00000246 RAX: ffffffff813aa4c9 RBX: ffffffff8175681d RCX: ffff88807cb4bc00 RDX: 0000000000000100 RSI: 0000000000000001 RDI: ffffffff8175681d RBP: ffffc900001f0438 R08: ffffc900001f04b0 R09: 0000000000000009 R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900001f03e8 R13: dffffc0000000000 R14: ffffc900001f041d R15: 0000000000000001 FS: 00007f8faaff66c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8faafd5d58 CR3: 0000000078da7000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff3 DR7: 0000000000000600 Call Trace: orc_find arch/x86/kernel/unwind_orc.c:202 [inline] unwind_next_frame+0x189/0x2970 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 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_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3519 dst_alloc+0x105/0x170 net/core/dst.c:89 ip6_dst_alloc net/ipv6/route.c:344 [inline] icmp6_dst_alloc+0x7b/0x400 net/ipv6/route.c:3306 ndisc_send_skb+0x419/0x14b0 net/ipv6/ndisc.c:493 addrconf_rs_timer+0x2bc/0x600 net/ipv6/addrconf.c:4006 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x52d/0x7d0 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+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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:finish_task_switch+0x26a/0x920 kernel/sched/core.c:5254 Code: 0f 84 37 01 00 00 48 85 db 0f 85 56 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 80 ca 14 09 e8 4b a4 2f 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc9000c637778 EFLAGS: 00000286 RAX: 0fdbb7808d6f0c00 RBX: 0000000000000000 RCX: 0fdbb7808d6f0c00 RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6f80 RBP: ffffc9000c6377d0 R08: ffffffff90d945ff R09: 1ffffffff21b28bf R10: dffffc0000000000 R11: fffffbfff21b28c0 R12: ffff88807cb4bc00 R13: dffffc0000000000 R14: ffff88802c6b3c00 R15: ffff8880b8f3cac8 context_switch kernel/sched/core.c:5383 [inline] __schedule+0x14da/0x44d0 kernel/sched/core.c:6699 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866 preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 smp_call_function_single+0x469/0x580 kernel/smp.c:652 task_function_call kernel/events/core.c:120 [inline] perf_install_in_context+0x591/0x8e0 kernel/events/core.c:2948 __do_sys_perf_event_open kernel/events/core.c:12915 [inline] __se_sys_perf_event_open+0x17fa/0x1c20 kernel/events/core.c:12567 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8facd8f749 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:00007f8faaff6038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f8facfe5fa0 RCX: 00007f8facd8f749 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007f8face13f91 R08: 0000000000000002 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8facfe6038 R14: 00007f8facfe5fa0 R15: 00007ffe3a95a0e8