hrtimer: interrupt took 49462 ns rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=964c/1/0x4000000000000000 softirq=11496/11497 fqs=2 rcu: (t=10501 jiffies g=10069 q=181 ncpus=2) rcu: rcu_preempt kthread starved for 10498 jiffies! g10069 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:26504 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5938 Comm: syz.2.19 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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_cmp4+0x2e/0x90 kernel/kcov.c:287 Code: 48 8b 04 24 65 48 8b 15 e0 41 7c 7e 65 8b 0d e1 41 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: 0000:ffffc900034b67e8 EFLAGS: 00000046 RAX: ffffffff813ba5e6 RBX: ffffffff81000000 RCX: 0000000000000100 RDX: ffff88802c291e00 RSI: 00000000000052d7 RDI: 000000000009c000 RBP: 000000000009c000 R08: ffff88802c291e00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900034b7f38 R13: 000000000009c001 R14: 00000000000052d7 R15: 0000000000000001 FS: 000055555a068500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000089 CR3: 000000007e05b000 CR4: 00000000003506f0 Call Trace: orc_find arch/x86/kernel/unwind_orc.c:211 [inline] unwind_next_frame+0x216/0x2990 arch/x86/kernel/unwind_orc.c:494 perf_callchain_kernel+0x42e/0x690 arch/x86/events/core.c:2780 get_perf_callchain+0x231/0x510 kernel/events/callchain.c:204 perf_callchain kernel/events/core.c:7734 [inline] perf_sample_save_callchain include/linux/perf_event.h:1232 [inline] perf_prepare_sample+0x3c7/0x1db0 kernel/events/core.c:7778 __perf_event_output kernel/events/core.c:7966 [inline] perf_event_output_forward+0x187/0x3e0 kernel/events/core.c:7987 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712 perf_swevent_overflow kernel/events/core.c:9795 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9846 perf_tp_event+0x620/0x1550 kernel/events/core.c:10373 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10292 perf_trace_preemptirq_template+0x269/0x330 include/trace/events/preemptirq.h:14 trace_irq_enable+0xbb/0xe0 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:_compound_head include/linux/page-flags.h:248 [inline] RIP: 0010:virt_to_folio include/linux/mm.h:1291 [inline] RIP: 0010:virt_to_slab mm/slab.h:218 [inline] RIP: 0010:kasan_addr_to_slab+0x30/0xd0 mm/kasan/common.c:37 Code: 89 fb e8 e3 4a 5d ff 84 c0 74 47 48 89 df e8 97 49 5d ff 48 c1 e8 06 48 83 e0 c0 48 ba 00 00 00 00 00 ea ff ff 48 8b 4c 10 08 c1 01 75 70 48 01 d0 66 90 48 8b 48 08 f6 c1 01 75 70 66 90 48 RSP: 0000:ffffc900034b72f0 EFLAGS: 00000206 RAX: 0000000000948100 RBX: ffff888025204b90 RCX: ffff88802c5b4280 RDX: ffffea0000000000 RSI: ffffffff8acadd60 RDI: ffff888025204b90 RBP: ffffc900034b7450 R08: ffffffff8e8c7caf R09: 1ffffffff1d18f95 R10: dffffc0000000000 R11: fffffbfff1d18f96 R12: dffffc0000000000 R13: 1ffff92000696e74 R14: ffff888025204b90 R15: 0000000000000000 __kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:477 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x900 kernel/rcu/tree.c:2837 refdst_drop include/net/dst.h:270 [inline] skb_dst_drop include/net/dst.h:282 [inline] __dev_queue_xmit+0x801/0x3630 net/core/dev.c:4405 neigh_output include/net/neighbour.h:543 [inline] ip6_finish_output2+0xe2e/0x1620 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+0xbb9/0x1480 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x36b/0x640 net/ipv6/addrconf.c:4036 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x570/0x810 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x27d/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+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0033:0x7f9d8439de99 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:00007fff53a8b208 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f9d8439de99 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f9d84625fa8 RBP: 0000000000000089 R08: 0000000000000000 R09: 0000000000000000 R10: 00007f9d84625fa0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9d84625fac R14: 00007f9d84625fa8 R15: 00007f9d84625fa0 CPU: 1 PID: 5937 Comm: syz.1.18 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:seqcount_lockdep_reader_access+0x19a/0x1d0 include/linux/seqlock.h:105 Code: 00 4d 85 e4 75 16 e8 95 cc 0f 00 eb 15 e8 8e cc 0f 00 e8 39 2d 15 09 4d 85 e4 74 ea e8 7f cc 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: ffffffff8177a851 RBX: 0000000000000000 RCX: ffff88802d710000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900001f02b8 R08: ffffffff911eb60f R09: 1ffffffff223d6c1 R10: dffffc0000000000 R11: fffffbfff223d6c2 R12: 0000000000000200 R13: 000001fb6dee09e6 R14: 1ffff9200003e040 R15: dffffc0000000000 FS: 0000555568bac500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000013cd CR3: 000000007a28f000 CR4: 00000000003506e0 Call Trace: timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get_with_offset+0x103/0x330 kernel/time/timekeeping.c:891 ktime_get_real include/linux/timekeeping.h:79 [inline] netif_rx_internal+0x33d/0x4e0 net/core/dev.c:5153 __netif_rx+0x78/0xc0 net/core/dev.c:5196 veth_forward_skb drivers/net/veth.c:325 [inline] veth_xmit+0x57a/0xa30 drivers/net/veth.c:378 __netdev_start_xmit include/linux/netdevice.h:4945 [inline] netdev_start_xmit include/linux/netdevice.h:4959 [inline] xmit_one net/core/dev.c:3644 [inline] dev_hard_start_xmit+0x269/0x790 net/core/dev.c:3660 __dev_queue_xmit+0x198c/0x3630 net/core/dev.c:4454 dev_queue_xmit include/linux/netdevice.h:3115 [inline] neigh_hh_output include/net/neighbour.h:527 [inline] neigh_output include/net/neighbour.h:541 [inline] ip6_finish_output2+0xdf7/0x1620 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+0xbb9/0x1480 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x36b/0x640 net/ipv6/addrconf.c:4036 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x570/0x810 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x27d/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:__syscall_enter_from_user_work kernel/entry/common.c:97 [inline] RIP: 0010:syscall_enter_from_user_mode+0x2e/0x80 kernel/entry/common.c:118 Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 e9 fa ff ff 66 90 66 90 e8 a0 06 01 f7 e8 5b 06 01 f7 fb 65 48 8b 05 12 dc 76 75 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 1d 46 e7 f6 48 RSP: 0018:ffffc90003497f08 EFLAGS: 00000286 RAX: ffff88802d710000 RBX: 00000000000000ca RCX: 03fcf1c306603e00 RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: ffffffff8b1d0660 RBP: ffffc90003497f48 R08: ffffffff8e8c7caf R09: 1ffffffff1d18f95 R10: dffffc0000000000 R11: fffffbfff1d18f96 R12: 0000000000000000 R13: 0000000000000000 R14: ffffc90003497f58 R15: 0000000000000000 do_syscall_64+0x28/0xb0 arch/x86/entry/common.c:72 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7efe61f9de99 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:00007ffd13e1b288 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007efe61f9de99 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007efe62225fac RBP: 00000000000013cd R08: 0000000000745aa0 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efe62225fac R14: 00007efe62225fa8 R15: 00007efe62225fa0