rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=cdf4/1/0x4000000000000000 softirq=33753/33760 fqs=4250 rcu: hardirqs softirqs csw/system rcu: number: 1034792 0 0 rcu: cputime: 13422 29726 57 ==> 43160(ms) rcu: (t=10502 jiffies g=35037 q=3074 ncpus=2) CPU: 1 PID: 9525 Comm: syz.7.785 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:seqcount_lockdep_reader_access+0x19a/0x1d0 include/linux/seqlock.h:105 Code: 00 4d 85 e4 75 16 e8 95 c6 0f 00 eb 15 e8 8e c6 0f 00 e8 69 ef 0e 09 4d 85 e4 74 ea e8 7f c6 0f 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc900001f0200 EFLAGS: 00000246 RAX: ffffffff81775b81 RBX: 0000000000000000 RCX: ffff88802b115a00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900001f02b8 R08: ffffffff911c55ef R09: 1ffffffff2238abd R10: dffffc0000000000 R11: fffffbfff2238abe R12: 0000000000000200 R13: 000001fb63109b96 R14: 1ffff9200003e040 R15: dffffc0000000000 FS: 00007f9d93e6b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa238f66000 CR3: 0000000061cc5000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: ktime_get_with_offset+0x94/0x330 kernel/time/timekeeping.c:889 ktime_get_real include/linux/timekeeping.h:79 [inline] net_timestamp_set net/core/dev.c:2207 [inline] dev_queue_xmit_nit+0x8ce/0xbb0 net/core/dev.c:2357 xmit_one net/core/dev.c:3640 [inline] dev_hard_start_xmit+0x148/0x740 net/core/dev.c:3660 sch_direct_xmit+0x25e/0x4c0 net/sched/sch_generic.c:345 __dev_xmit_skb net/core/dev.c:3881 [inline] __dev_queue_xmit+0x165d/0x3660 net/core/dev.c:4416 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:finish_task_switch+0x26a/0x8f0 kernel/sched/core.c:5255 Code: 0f 84 33 01 00 00 48 85 db 0f 85 52 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 00 89 32 09 e8 9b 29 30 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:ffffc900045ff558 EFLAGS: 00000282 RAX: d48c1666824fce00 RBX: 0000000000000000 RCX: d48c1666824fce00 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8e60 RBP: ffffc900045ff5b0 R08: ffffffff911c5517 R09: 1ffffffff2238aa2 R10: dffffc0000000000 R11: fffffbfff2238aa3 R12: ffff88802b115a00 R13: dffffc0000000000 R14: ffff888027ec0000 R15: ffff8880b8f3cac8 context_switch kernel/sched/core.c:5384 [inline] __schedule+0x155b/0x45a0 kernel/sched/core.c:6700 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758 Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc900045ff940 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: d48c1666824fce00 RDX: 0000000000000000 RSI: ffffffff8acadb60 RDI: ffffffff8b1c8e60 RBP: ffffc900045ffa60 R08: dffffc0000000000 R09: 1ffffffff2238aa2 R10: dffffc0000000000 R11: fffffbfff2238aa3 R12: 1ffff920008bff34 R13: ffffffff8d15bd70 R14: 0000000000000246 R15: dffffc0000000000 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:768 [inline] exit_signals+0x60/0x500 kernel/signal.c:2994 do_exit+0x5fe/0x2460 kernel/exit.c:830 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: 0033:0x7f9d92f9c819 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:00007f9d93e6b028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000005 RBX: 00007f9d93215fa0 RCX: 00007f9d92f9c819 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007f9d93032c91 R08: 0000000000000002 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9d93216038 R14: 00007f9d93215fa0 R15: 00007ffef31d2248