rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=d324/1/0x4000000000000000 softirq=14578/14590 fqs=4363 rcu: hardirqs softirqs csw/system rcu: number: 1374136 0 0 rcu: cputime: 18859 33630 67 ==> 52490(ms) rcu: (t=10500 jiffies g=14565 q=996 ncpus=2) CPU: 1 PID: 6677 Comm: syz.2.245 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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_const_cmp4+0x2e/0x90 kernel/kcov.c:313 Code: 48 8b 04 24 65 48 8b 15 00 90 7c 7e 65 8b 0d 01 90 7c 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 <74> 52 8b 8a f8 15 00 00 83 f9 03 75 47 48 8b 8a 00 16 00 00 44 8b RSP: 0018:ffffc900001f0420 EFLAGS: 00000246 RAX: ffffffff88735880 RBX: 0000000000000001 RCX: 0000000000000100 RDX: ffff888059513c00 RSI: 0000000000000001 RDI: 0000000000000007 RBP: 0000000000000001 R08: ffff88801cb8c4a7 R09: 1ffff11003971894 R10: dffffc0000000000 R11: ffffed1003971895 R12: dffffc0000000000 R13: ffffffff8b68f480 R14: ffff88801cb8c3c0 R15: dffffc0000000000 FS: 00007ff65e2246c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2f6b6c CR3: 000000002e54c000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: cpu_max_bits_warn include/linux/cpumask.h:143 [inline] cpumask_check include/linux/cpumask.h:150 [inline] cpumask_test_cpu include/linux/cpumask.h:504 [inline] cpu_online include/linux/cpumask.h:1082 [inline] trace_consume_skb+0x30/0x1c0 include/trace/events/skb.h:54 consume_skb+0x73/0x110 net/core/skbuff.c:1286 nsim_start_xmit+0x9e/0xc0 drivers/net/netdevsim/netdev.c:42 __netdev_start_xmit include/linux/netdevice.h:4943 [inline] netdev_start_xmit include/linux/netdevice.h:4957 [inline] xmit_one net/core/dev.c:3644 [inline] dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3660 __dev_queue_xmit+0x19a3/0x3660 net/core/dev.c:4454 dev_queue_xmit include/linux/netdevice.h:3113 [inline] neigh_hh_output include/net/neighbour.h:527 [inline] neigh_output include/net/neighbour.h:541 [inline] ip6_finish_output2+0xe06/0x1630 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:generic_exec_single+0x481/0x4f0 kernel/smp.c:418 Code: 75 11 e8 42 05 0b 00 48 85 db 75 16 e8 38 05 0b 00 eb 15 e8 31 05 0b 00 e8 0c 3e 0a 09 48 85 db 74 ea e8 22 05 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:ffffc9001a167a00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000 RDX: ffffc9000cb99000 RSI: 00000000000029d4 RDI: 00000000000029d5 RBP: ffffc9001a167ad0 R08: ffffffff911c55ff R09: 1ffffffff2238abf R10: dffffc0000000000 R11: fffffbfff2238ac0 R12: 1ffff9200342cf44 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff9200342cf65 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:2959 __do_sys_perf_event_open kernel/events/core.c:12957 [inline] __se_sys_perf_event_open+0x1836/0x1c50 kernel/events/core.c:12609 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: 0033:0x7ff65d39c819 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:00007ff65e224028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007ff65d615fa0 RCX: 00007ff65d39c819 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007ff65d432c91 R08: 0000000000000002 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff65d616038 R14: 00007ff65d615fa0 R15: 00007ffed8fa5398