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INFO: rcu detected stall in ip_list_rcv

Status: upstream: reported on 2025/12/04 02:09
Reported-by: syzbot+70204a71afdd800448da@syzkaller.appspotmail.com
First crash: 156d, last: 11d
▶ ▼ Similar bugs (17)
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 1474d 1474d 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 466d 466d 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 603d 658d 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 619d 619d 0/3 auto-obsoleted due to no activity on 2024/12/06 18:02
linux-5.15 INFO: rcu detected stall in ip_list_rcv (2) 1 2 118d 197d 0/3 auto-obsoleted due to no activity on 2026/04/21 10:23
upstream INFO: rcu detected stall in ip_list_rcv (6) net 1 C done done 58 28d 887d 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 1030d 1089d 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 2048d 2074d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in ip_list_rcv (4) netfilter 1 1 1406d 1406d 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 1902d 1981d 0/29 auto-closed as invalid on 2021/05/23 12:59
linux-6.1 INFO: rcu detected stall in ip_list_rcv (3) 1 1 238d 238d 0/3 auto-obsoleted due to no activity on 2025/12/22 08:55
upstream INFO: rcu detected stall in ip_list_rcv (3) net 1 1 1594d 1594d 0/29 closed as invalid on 2022/02/08 10:10
android-5-15 BUG: soft lockup in ip_list_rcv 1 20 592d 746d 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 645d 667d 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 409d 409d 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 641d 641d 0/2 auto-obsoleted due to no activity on 2024/11/04 20:30
upstream BUG: soft lockup in ip_list_rcv net 1 1 1975d 1975d 0/29 auto-closed as invalid on 2021/03/11 09:36

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 13336 jiffies s: 46785 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 19770 Comm: syz.3.4411 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:trace_irq_disable+0xc2/0xe0 include/trace/events/preemptirq.h:36
Code: 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 f7 e8 02 c4 51 00 49 8b 3e 48 89 de 31 d2 e8 35 f9 ff ff 65 ff 0d 86 20 76 7e <0f> 85 3d ff ff ff e8 33 08 73 ff e9 33 ff ff ff 0f 0b eb 80 66 2e
RSP: 0018:ffffc900001ef7d8 EFLAGS: 00000002
RAX: dab4cea7600c3a00 RBX: ffffffff8a868367 RCX: dab4cea7600c3a00
RDX: 0000000000000000 RSI: ffffffff8b1c8fc0 RDI: ffffffff8b1c8f80
RBP: 0000000000000000 R08: ffffffff8e8b19ef R09: 1ffffffff1d1633d
R10: dffffc0000000000 R11: fffffbfff1d1633e R12: 0000000000000000
R13: 0000000000000000 R14: ffff88807e653798 R15: 0000000000000000
FS:  00007f5059f206c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f22505e8158 CR3: 000000002543a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 irqentry_enter+0x37/0x50 kernel/entry/common.c:381
 sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1088
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:275 [inline]
RIP: 0010:read_seqbegin+0x19a/0x270 include/linux/seqlock.h:893
Code: 11 e8 6a de 08 f9 4d 85 f6 75 16 e8 60 de 08 f9 eb 15 e8 59 de 08 f9 e8 34 37 08 02 4d 85 f6 74 ea e8 4a de 08 f9 fb 49 89 df <49> c1 ef 03 43 0f b6 04 2f 84 c0 0f 85 94 00 00 00 44 8b 33 44 89
RSP: 0018:ffffc900001ef8c0 EFLAGS: 00000246
RAX: ffffffff887e43b6 RBX: ffff88807bbb7930 RCX: ffff88804ddfbc00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900001ef990 R08: ffffffff911c65cf R09: 1ffffffff2238cb9
R10: dffffc0000000000 R11: fffffbfff2238cba R12: 1ffff9200003df1c
R13: dffffc0000000000 R14: 0000000000000200 R15: ffff88807bbb7930
 neigh_resolve_output+0x435/0x730 net/core/neighbour.c:1562
 neigh_output include/net/neighbour.h:543 [inline]
 ip_finish_output2+0xd3a/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_queue_xmit+0x1049/0x1950 net/ipv4/ip_output.c:540
 __tcp_transmit_skb+0x1d6b/0x33f0 net/ipv4/tcp_output.c:1425
 tcp_rcv_established+0x1307/0x1d20 net/ipv4/tcp_input.c:6144
 tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1735
 tcp_v4_rcv+0x23bf/0x2af0 net/ipv4/tcp_ipv4.c:2167
 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+0x583/0x750 net/core/dev.c:5737
 __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]
 gro_normal_one include/net/gro.h:464 [inline]
 napi_skb_finish net/core/gro.c:575 [inline]
 napi_gro_receive+0x565/0xb00 net/core/gro.c:605
 receive_buf+0x2203/0x3820 drivers/net/virtio_net.c:1870
 virtnet_receive drivers/net/virtio_net.c:2155 [inline]
 virtnet_poll+0x5dd/0x1280 drivers/net/virtio_net.c:2229
 __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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:generic_exec_single+0x481/0x4f0 kernel/smp.c:418
Code: 75 11 e8 42 05 0b 00 48 85 db 75 16 e8 38 05 0b 00 eb 15 e8 31 05 0b 00 e8 0c 5e 0a 09 48 85 db 74 ea e8 22 05 0b 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 43 c7 44 2c 08
RSP: 0018:ffffc900036e7a00 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000
RDX: ffffc9000d3ca000 RSI: 0000000000005aec RDI: 0000000000005aed
RBP: ffffc900036e7ad0 R08: ffffffff911c65ff R09: 1ffffffff2238cbf
R10: dffffc0000000000 R11: fffffbfff2238cc0 R12: 1ffff920006dcf44
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920006dcf65
 smp_call_function_single+0x36d/0x5a0 kernel/smp.c:647
 task_function_call kernel/events/core.c:120 [inline]
 perf_install_in_context+0x5be/0x920 kernel/events/core.c:2959
 __do_sys_perf_event_open kernel/events/core.c:12957 [inline]
 __se_sys_perf_event_open+0x1836/0x1c50 kernel/events/core.c:12609
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5058f9cdd9
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:00007f5059f20028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f5059215fa0 RCX: 00007f5058f9cdd9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007f5059032d69 R08: 0000000000000002 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5059216038 R14: 00007f5059215fa0 R15: 00007ffd93a5b7a8
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/28 19:05 linux-6.6.y 142cd8382222 ce741359 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in ip_list_rcv
2026/02/15 10:26 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in ip_list_rcv
2025/12/04 02:08 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in ip_list_rcv
2026/04/18 00:37 linux-6.6.y 8cee53b8eaeb 24ecfc1e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf BUG: soft lockup in ip_list_rcv
* Struck through repros no longer work on HEAD.