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INFO: rcu detected stall in ip_list_rcv (3)

Status: upstream: reported on 2025/09/13 08:55
Reported-by: syzbot+c1cd7459a9244e3fd84d@syzkaller.appspotmail.com
First crash: 9h41m, last: 9h41m
▶ ▼ Similar bugs (14)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: soft lockup in ip_list_rcv (2) kvm 1 8 1236d 1236d 0/29 auto-closed as invalid on 2022/06/25 08:42
linux-6.1 INFO: rcu detected stall in ip_list_rcv (2) 1 1 228d 228d 0/3 auto-obsoleted due to no activity on 2025/05/08 11:17
linux-5.15 INFO: rcu detected stall in ip_list_rcv 1 2 364d 420d 0/3 auto-obsoleted due to no activity on 2024/12/22 19:35
linux-6.1 INFO: rcu detected stall in ip_list_rcv 1 1 381d 381d 0/3 auto-obsoleted due to no activity on 2024/12/06 18:02
upstream INFO: rcu detected stall in ip_list_rcv (6) net 1 C done done 50 46d 649d 0/29 upstream: reported C repro on 2023/12/04 09:45
upstream INFO: rcu detected stall in ip_list_rcv (5) lsm netfilter 1 3 792d 851d 0/29 auto-obsoleted due to no activity on 2023/10/11 22:12
upstream INFO: rcu detected stall in ip_list_rcv net 1 C error done 3 1809d 1836d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in ip_list_rcv (4) netfilter 1 1 1168d 1168d 0/29 auto-closed as invalid on 2022/09/01 16:20
upstream INFO: rcu detected stall in ip_list_rcv (2) netfilter 1 3 1664d 1743d 0/29 auto-closed as invalid on 2021/05/23 12:59
upstream INFO: rcu detected stall in ip_list_rcv (3) net 1 1 1356d 1356d 0/29 closed as invalid on 2022/02/08 10:10
android-5-15 BUG: soft lockup in ip_list_rcv 1 20 354d 508d 0/2 auto-obsoleted due to no activity on 2024/12/22 22:06
android-6-1 BUG: soft lockup in ip_list_rcv 1 2 406d 429d 0/2 auto-obsoleted due to no activity on 2024/10/31 19:10
android-5-15 BUG: soft lockup in ip_list_rcv (2) 1 1 171d 171d 0/2 auto-obsoleted due to no activity on 2025/06/24 13:43
android-5-10 BUG: soft lockup in ip_list_rcv 1 1 402d 402d 0/2 auto-obsoleted due to no activity on 2024/11/04 20:30

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { P11888 0-.... } 2690 jiffies s: 45929 root: 0x1/T
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11888 Comm: syz.8.2212 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:244 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp8+0x4/0x80 kernel/kcov.c:293
Code: 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 04 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 <65> 48 8b 0d c4 9c 81 7e 65 8b 15 c5 9c 81 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc900000058e8 EFLAGS: 00000046
RAX: ffffffff8170c237 RBX: ffff8880746de760 RCX: ffff888032099dc0
RDX: 0000000000010100 RSI: 0000007cfeeba9da RDI: 0000007cfeec070b
RBP: 0000007cfeec070b R08: dffffc0000000000 R09: fffffbfff1c3eea6
R10: fffffbfff1c3eea6 R11: 1ffffffff1c3eea5 R12: 0000000000005d31
R13: 0000007cfeeba9da R14: 1ffff1100e8dbcef R15: ffff8880746de778
FS:  00007f941d04a6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f941d029d58 CR3: 00000000583bf000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 hrtimer_forward+0xf7/0x290 kernel/time/hrtimer.c:-1
 hrtimer_forward_now include/linux/hrtimer.h:509 [inline]
 perf_swevent_hrtimer+0x443/0x500 kernel/events/core.c:10932
 __run_hrtimer kernel/time/hrtimer.c:1752 [inline]
 __hrtimer_run_queues+0x515/0xd60 kernel/time/hrtimer.c:1816
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1878
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1118
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:bpf_tree_comp kernel/bpf/core.c:626 [inline]
RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline]
RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
RIP: 0010:bpf_ksym_find kernel/bpf/core.c:702 [inline]
RIP: 0010:is_bpf_text_address+0x123/0x2a0 kernel/bpf/core.c:736
Code: 4d 85 ff 0f 84 be 00 00 00 4c 89 24 24 c1 e3 03 8d 2c 5b 48 f7 dd 4d 8d a4 2f e0 fd ff ff 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 e7 e8 13 9f 43 00 4d 8b 24 24 4c 89 e7 4c 89 f6 e8 a4
RSP: 0018:ffffc90000005f30 EFLAGS: 00000246
RAX: 1ffff1100a4e8e28 RBX: 0000000000000000 RCX: ffff888032099dc0
RDX: 0000000000000100 RSI: ffffffff8adefc80 RDI: ffffffff8adefc40
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: ffff888052747140
R13: dffffc0000000000 R14: 00007f941c18eba9 R15: ffff888052747360
 kernel_text_address+0x9c/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x30 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x290 mm/slub.c:3709
 __dev_kfree_skb_any+0x11b/0x140 net/core/dev.c:3210
 free_old_xmit_skbs+0x111/0x2a0 drivers/net/virtio_net.c:1639
 start_xmit+0x168/0x16e0 drivers/net/virtio_net.c:1901
 __netdev_start_xmit include/linux/netdevice.h:4896 [inline]
 netdev_start_xmit include/linux/netdevice.h:4910 [inline]
 xmit_one net/core/dev.c:3670 [inline]
 dev_hard_start_xmit+0x262/0x870 net/core/dev.c:3686
 sch_direct_xmit+0x24e/0x4a0 net/sched/sch_generic.c:342
 __dev_xmit_skb net/core/dev.c:3907 [inline]
 __dev_queue_xmit+0x18cd/0x3760 net/core/dev.c:4312
 dev_queue_xmit include/linux/netdevice.h:3051 [inline]
 neigh_hh_output include/net/neighbour.h:529 [inline]
 neigh_output include/net/neighbour.h:543 [inline]
 ip_finish_output2+0xbe8/0x11b0 net/ipv4/ip_output.c:228
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0x1030/0x19b0 net/ipv4/ip_output.c:532
 __tcp_transmit_skb+0x1c6c/0x3160 net/ipv4/tcp_output.c:1405
 tcp_validate_incoming+0xe6b/0x2140 net/ipv4/tcp_input.c:5832
 tcp_rcv_established+0xb94/0x1d30 net/ipv4/tcp_input.c:6098
 tcp_v4_do_rcv+0x48d/0xb00 net/ipv4/tcp_ipv4.c:1683
 tcp_v4_rcv+0x2789/0x2e30 net/ipv4/tcp_ipv4.c:2114
 ip_protocol_deliver_rcu+0x3ad/0x780 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2c7/0x510 net/ipv4/ip_input.c:233
 NF_HOOK+0x2ff/0x390 include/linux/netfilter.h:302
 dst_input include/net/dst.h:463 [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+0xa30/0xd10 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3df/0x430 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5624 [inline]
 __netif_receive_skb_list_core+0x574/0x740 net/core/dev.c:5672
 __netif_receive_skb_list net/core/dev.c:5724 [inline]
 netif_receive_skb_list_internal+0x90f/0xc50 net/core/dev.c:5815
 gro_normal_list include/net/gro.h:433 [inline]
 napi_complete_done+0x37d/0x830 net/core/dev.c:6156
 virtqueue_napi_complete drivers/net/virtio_net.c:403 [inline]
 virtnet_poll+0x991/0x1150 drivers/net/virtio_net.c:1717
 __napi_poll+0xc0/0x460 net/core/dev.c:6590
 napi_poll net/core/dev.c:6657 [inline]
 net_rx_action+0x5b1/0xad0 net/core/dev.c:6771
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:finish_task_switch+0x26a/0x8f0 kernel/sched/core.c:5123
Code: 0f 84 3b 01 00 00 48 85 db 0f 85 5a 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 70 e0 c8 08 e8 2b b3 2e 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:ffffc90003d7f858 EFLAGS: 00000282
RAX: 6b3f76bbd66ad100 RBX: 0000000000000000 RCX: 6b3f76bbd66ad100
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: ffffffff8adefca0
RBP: ffffc90003d7f8b0 R08: dffffc0000000000 R09: ffffed10171c7559
R10: ffffed10171c7559 R11: 1ffff110171c7558 R12: ffff888032099dc0
R13: dffffc0000000000 R14: ffff88805573d940 R15: ffff8880b8e3b590
 context_switch kernel/sched/core.c:5247 [inline]
 __schedule+0x10f4/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 bpf_test_timer_leave+0x129/0x150 net/bpf/test_run.c:51
 bpf_test_timer_continue+0x291/0x380 net/bpf/test_run.c:80
 bpf_prog_test_run_flow_dissector+0x429/0x600 net/bpf/test_run.c:1486
 bpf_prog_test_run+0x31e/0x390 kernel/bpf/syscall.c:3692
 __sys_bpf+0x593/0x6d0 kernel/bpf/syscall.c:5045
 __do_sys_bpf kernel/bpf/syscall.c:5131 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5129 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5129
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f941c18eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f941d04a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f941c3d5fa0 RCX: 00007f941c18eba9
RDX: 0000000000000050 RSI: 0000200000000000 RDI: 000000000000000a
RBP: 00007f941c211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f941c3d6038 R14: 00007f941c3d5fa0 R15: 00007ffc6911b728
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/13 08:54 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in ip_list_rcv
* Struck through repros no longer work on HEAD.