rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=c8d/1/0x4000000000000000 softirq=25539/25544 fqs=3832 (t=10500 jiffies g=33613 q=1693) NMI backtrace for cpu 0 CPU: 0 PID: 10497 Comm: syz.3.2358 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x22d/0x380 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x31f/0x5f0 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x6ec/0x1120 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:2021 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline] RIP: 0010:write_comp_data kernel/kcov.c:227 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0x70/0xe0 kernel/kcov.c:329 Code: 20 65 4c 8b 05 61 6e 89 7e 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 4f 6e 89 7e 41 81 e3 00 01 ff 00 <74> 13 41 81 fb 00 01 00 00 75 d9 41 83 b8 34 16 00 00 00 74 cf 45 RSP: 0018:ffffc900000072b8 EFLAGS: 00000206 RAX: 0000000000000002 RBX: ffffc90000007420 RCX: 0000000000000005 RDX: ffffffff88a022b1 RSI: ffffffff8d544520 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff888076ac9dc0 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000100 R12: ffffc900000073e8 R13: ffff8880796fb500 R14: 0000000000000000 R15: 0000000000000000 ipv6_get_saddr_eval+0xc1/0xf40 net/ipv6/addrconf.c:1548 __ipv6_dev_get_saddr+0x19d/0x430 net/ipv6/addrconf.c:1714 ipv6_dev_get_saddr+0x297/0xb90 net/ipv6/addrconf.c:1851 ip6_route_get_saddr include/net/ip6_route.h:145 [inline] ip6_dst_lookup_tail+0xe03/0x1340 net/ipv6/ip6_output.c:1106 icmpv6_route_lookup+0xfe/0x5a0 net/ipv6/icmp.c:366 icmp6_send+0xff0/0x19a0 net/ipv6/icmp.c:601 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x35/0x490 net/ipv6/route.c:2789 dst_link_failure include/net/dst.h:422 [inline] ndisc_error_report+0x10e/0x150 net/ipv6/ndisc.c:717 neigh_invalidate+0x23b/0x460 net/core/neighbour.c:1001 neigh_timer_handler+0x90d/0xff0 net/core/neighbour.c:1088 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x56c/0x810 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:finish_lock_switch+0x12f/0x290 kernel/sched/core.c:4804 Code: 83 c7 18 be ff ff ff ff e8 6e cb 6b 08 85 c0 74 46 4d 85 ff 75 62 0f 1f 44 00 00 48 89 df e8 98 3a 75 08 e8 43 d7 2a 00 fb 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 2f 0e fe ff 43 80 3c 2c RSP: 0018:ffffc9000326f7b8 EFLAGS: 00000282 RAX: ccf79a80dcd93d00 RBX: ffff88807a241dc0 RCX: ccf79a80dcd93d00 RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a4200 RBP: 1ffff11017207613 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: 1ffff110172075c1 R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000 finish_task_switch+0x12f/0x650 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11cb/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 freezable_schedule include/linux/freezer.h:172 [inline] futex_wait_queue_me+0x22b/0x440 kernel/futex/core.c:2863 futex_wait+0x256/0x680 kernel/futex/core.c:2964 do_futex+0xdc2/0x12b0 kernel/futex/core.c:3983 __do_sys_futex kernel/futex/core.c:4060 [inline] __se_sys_futex+0x389/0x420 kernel/futex/core.c:4041 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa0b929e0d9 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:00007fa0b74f60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fa0b9525fa8 RCX: 00007fa0b929e0d9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa0b9525fa8 RBP: 00007fa0b9525fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa0b9526038 R14: 00007ffd6c207ca0 R15: 00007ffd6c207d88