rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (9891 ticks this GP) idle=6614/1/0x4000000000000000 softirq=35498/35501 fqs=4945 rcu: hardirqs softirqs csw/system rcu: number: 1801091 3 0 rcu: cputime: 23730 28758 36 ==> 52490(ms) rcu: (t=10500 jiffies g=49721 q=1804 ncpus=2) CPU: 0 PID: 11614 Comm: syz.3.2019 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 0b 74 cc f6 65 8b 05 4c a1 73 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90000007a60 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 895dd7958355a200 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001 RBP: ffffc90000007ae8 R08: ffffffff911c65e7 R09: 1ffffffff2238cbc R10: dffffc0000000000 R11: fffffbfff2238cbd R12: dffffc0000000000 R13: ffff88802c638410 R14: ffff8880b8e29580 R15: 1ffff92000000f4c FS: 00007faacfd2e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f371783be6a CR3: 000000002bbf3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __mod_timer+0x984/0xdb0 kernel/time/timer.c:1134 mrp_join_timer_arm net/802/mrp.c:596 [inline] mrp_join_timer+0x13f/0x170 net/802/mrp.c:611 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:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 51 d6 cd f6 e8 7c e3 fe f6 fb bf 01 00 00 00 f1 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc9000bd67d60 EFLAGS: 00000286 RAX: 895dd7958355a200 RBX: 0000000000000000 RCX: 895dd7958355a200 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001 RBP: ffffc9000bd67e10 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920017acfac 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:exit_to_user_mode_loop+0x40/0x110 kernel/entry/common.c:164 Code: fb eb 1d e8 d2 a6 12 09 65 48 8b 05 ba dc 8f 7e 4c 8b 30 41 f7 c6 0e 30 02 00 0f 84 c4 00 00 00 e8 f5 ba 19 00 fb 41 f6 c6 08 <74> 05 e8 09 d2 1a 09 41 f7 c6 00 10 00 00 74 08 48 89 df e8 78 a0 RSP: 0018:ffffc9000bd67ed0 EFLAGS: 00000246 RAX: 895dd7958355a200 RBX: ffffc9000bd67f58 RCX: 895dd7958355a200 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8fa0 RBP: ffffc9000bd67f48 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000004006 R15: ffff888019fb0000 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: 0033:0x7faaced9cdd9 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:00007faacfd2e028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000015 RBX: 00007faacf015fa0 RCX: 00007faaced9cdd9 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000100 RBP: 00007faacee32d69 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007faacf016038 R14: 00007faacf015fa0 R15: 00007ffdcb6c8188 NMI backtrace for cpu 0 CPU: 0 PID: 11614 Comm: syz.3.2019 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:perf_callchain_user+0xd12/0x15c0 include/linux/perf_event.h:-1 Code: 42 80 3c 38 00 74 08 4c 89 f7 e8 f9 18 de 00 49 89 2e 48 8b 44 24 18 42 0f b6 04 38 84 c0 0f 85 06 01 00 00 48 8b 04 24 ff 00 <4c> 8b 74 24 08 48 8b 44 24 18 42 0f b6 04 38 84 c0 0f 85 8c 00 00 RSP: 0018:ffffc90000005be0 EFLAGS: 00000002 RAX: ffffc90000005ccc RBX: 00000000ffffffff RCX: 000000000000002a RDX: 000000000000002b RSI: 000000000000007f RDI: 0000000000000028 RBP: 73646e6168206461 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 0000000000000028 R13: 6200786c6c257830 R14: ffff88805e6c8598 R15: dffffc0000000000 FS: 00007faacfd2e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f371783be6a CR3: 000000002bbf3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: get_perf_callchain+0x394/0x510 kernel/events/callchain.c:219 perf_callchain kernel/events/core.c:7742 [inline] perf_sample_save_callchain include/linux/perf_event.h:1232 [inline] perf_prepare_sample+0x3c7/0x1df0 kernel/events/core.c:7786 __perf_event_output kernel/events/core.c:7974 [inline] perf_event_output_forward+0x187/0x3e0 kernel/events/core.c:7995 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9720 perf_swevent_overflow kernel/events/core.c:9803 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9854 perf_tp_event+0x5f9/0x1520 kernel/events/core.c:10381 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10300 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: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 0f 0f 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:ffffc90000006540 EFLAGS: 00000246 RAX: ffffffff81775b81 RBX: 0000000000000000 RCX: ffff888019fb0000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900000065f8 R08: ffffffff911c65c7 R09: 1ffffffff2238cb8 R10: dffffc0000000000 R11: fffffbfff2238cb9 R12: 0000000000000200 R13: 000001fb63109b96 R14: 1ffff92000000ca8 R15: dffffc0000000000 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] 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 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] ip_finish_output2+0xcec/0x11e0 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip_output+0x2a1/0x3b0 net/ipv4/ip_output.c:436 dst_output include/net/dst.h:467 [inline] ip_local_out net/ipv4/ip_output.c:129 [inline] ip_send_skb+0x12f/0x1d0 net/ipv4/ip_output.c:1498 ip_push_pending_frames net/ipv4/ip_output.c:1518 [inline] ip_send_unicast_reply+0xd40/0x1530 net/ipv4/ip_output.c:1662 tcp_v4_send_reset+0x14fc/0x23e0 net/ipv4/tcp_ipv4.c:847 tcp_v4_rcv+0x208c/0x2af0 net/ipv4/tcp_ipv4.c:2195 ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233 NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304 dst_input include/net/dst.h:477 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0xa4c/0xd70 net/ipv4/ip_input.c:639 ip_list_rcv+0x3f2/0x440 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5689 [inline] __netif_receive_skb_list_core+0x2da/0x750 net/core/dev.c:5727 __netif_receive_skb_list net/core/dev.c:5789 [inline] netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5880 gro_normal_list include/net/gro.h:451 [inline] napi_complete_done+0x329/0x820 net/core/dev.c:6220 virtqueue_napi_complete drivers/net/virtio_net.c:450 [inline] virtnet_poll+0xa9c/0x1280 drivers/net/virtio_net.c:2236 __napi_poll+0xc0/0x460 net/core/dev.c:6650 napi_poll net/core/dev.c:6717 [inline] net_rx_action+0x616/0xc40 net/core/dev.c:6853 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:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 51 d6 cd f6 e8 7c e3 fe f6 fb bf 01 00 00 00 f1 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc9000bd67d60 EFLAGS: 00000286 RAX: 895dd7958355a200 RBX: 0000000000000000 RCX: 895dd7958355a200 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001 RBP: ffffc9000bd67e10 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920017acfac 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:exit_to_user_mode_loop+0x40/0x110 kernel/entry/common.c:164 Code: fb eb 1d e8 d2 a6 12 09 65 48 8b 05 ba dc 8f 7e 4c 8b 30 41 f7 c6 0e 30 02 00 0f 84 c4 00 00 00 e8 f5 ba 19 00 fb 41 f6 c6 08 <74> 05 e8 09 d2 1a 09 41 f7 c6 00 10 00 00 74 08 48 89 df e8 78 a0 RSP: 0018:ffffc9000bd67ed0 EFLAGS: 00000246 RAX: 895dd7958355a200 RBX: ffffc9000bd67f58 RCX: 895dd7958355a200 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8fa0 RBP: ffffc9000bd67f48 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000004006 R15: ffff888019fb0000 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: 0033:0x7faaced9cdd9 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:00007faacfd2e028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000015 RBX: 00007faacf015fa0 RCX: 00007faaced9cdd9 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000100 RBP: 00007faacee32d69 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007faacf016038 R14: 00007faacf015fa0 R15: 00007ffdcb6c8188