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INFO: rcu detected stall in ip_rcv (7)

Status: auto-obsoleted due to no activity on 2026/03/20 17:26
Subsystems: net modules
[Documentation on labels]
First crash: 239d, last: 99d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
7b514950-0416-4142-bc15-309f87c9d110 repro INFO: rcu detected stall in ip_rcv (7) 2026/03/06 04:04 2026/03/06 04:04 2026/03/06 04:13 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 BUG: soft lockup in ip_rcv 1 C error 16 1123d 1791d 0/1 upstream: reported C repro on 2021/05/04 03:32
upstream INFO: rcu detected stall in ip_rcv netfilter 1 2 2438d 2601d 0/29 auto-closed as invalid on 2019/10/25 14:11
upstream INFO: rcu detected stall in ip_rcv (2) net 1 1 1944d 1944d 0/29 auto-closed as invalid on 2021/03/01 14:28
linux-4.14 INFO: rcu detected stall in ip_rcv (2) 1 1 1955d 1955d 0/1 auto-closed as invalid on 2021/03/20 21:11
upstream INFO: rcu detected stall in ip_rcv (6) netfilter 1 4 343d 487d 0/29 auto-obsoleted due to no activity on 2025/07/19 18:54
upstream INFO: rcu detected stall in ip_rcv (3) kernel 1 1 1806d 1806d 0/29 auto-closed as invalid on 2021/07/17 18:11
linux-4.14 INFO: rcu detected stall in ip_rcv 1 3 2135d 2154d 0/1 auto-closed as invalid on 2020/09/21 12:55
upstream INFO: rcu detected stall in ip_rcv (4) net bpf 1 12 1434d 1505d 0/29 auto-closed as invalid on 2022/07/25 09:18
upstream INFO: rcu detected stall in ip_rcv (5) net 1 2 948d 960d 0/29 auto-obsoleted due to no activity on 2023/11/23 01:36
linux-4.14 BUG: soft lockup in ip_rcv (2) 1 1 1827d 1827d 0/1 auto-closed as invalid on 2021/07/26 15:49
linux-4.14 BUG: soft lockup in ip_rcv (3) 1 C error 4 1303d 1423d 0/1 upstream: reported C repro on 2022/05/07 10:08
android-6-1 BUG: soft lockup in ip_rcv origin:lts 1 C error 4 79d 156d 0/2 upstream: reported C repro on 2025/10/25 08:20
linux-4.14 BUG: soft lockup in ip_rcv 1 1 1990d 1990d 0/1 auto-closed as invalid on 2021/02/14 05:25

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P25635
rcu: 	(detected by 1, t=10502 jiffies, g=138149, q=971639 ncpus=2)
task:syz.9.4949      state:R  running task     stack:27688 pid:25635 tgid:25630 ppid:20328  task_flags:0x400040 flags:0x00080012
Call Trace:
 <IRQ>
 sched_show_task kernel/sched/core.c:7819 [inline]
 sched_show_task+0x423/0x630 kernel/sched/core.c:7794
 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
 print_other_cpu_stall kernel/rcu/tree_stall.h:681 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:856 [inline]
 rcu_pending kernel/rcu/tree.c:3667 [inline]
 rcu_sched_clock_irq+0x2634/0x31f0 kernel/rcu/tree.c:2704
 update_process_times+0x178/0x2d0 kernel/time/timer.c:2474
 tick_sched_handle kernel/time/tick-sched.c:298 [inline]
 tick_nohz_handler+0x506/0x720 kernel/time/tick-sched.c:319
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x64e/0xc40 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:57
Code: e8 b5 5d 24 f6 e8 40 7c f4 ff 90 65 ff 0d 08 91 3a 08 e9 40 ff ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 c7 c6 00 b3 f2 8b 48 c7 c7 40 b3 f2 8b e9 f9 fe ff
RSP: 0018:ffffc90000a07e68 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000002958106c
RDX: ffffffff816cb66d RSI: ffffffff8daa7d80 RDI: ffffffff8bf2b380
RBP: ffffc90000a07f90 R08: 00000000b6995195 R09: 000000005b699519
R10: 0000000000000002 R11: ffff88807599aff0 R12: fffff52000140feb
R13: ffffc90000a07f48 R14: ffffc90000a07f48 R15: ffffc90000a07f50
 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
 rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:751
 rcu_read_lock include/linux/rcupdate.h:868 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xa86/0x20b0 arch/x86/kernel/unwind_orc.c:495
 __unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:773
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_noprof+0x25e/0x770 mm/slub.c:5270
 kmem_alloc_batch+0x49/0x170 lib/debugobjects.c:371
 fill_pool lib/debugobjects.c:403 [inline]
 debug_objects_fill_pool lib/debugobjects.c:725 [inline]
 debug_objects_fill_pool+0x413/0x660 lib/debugobjects.c:697
 debug_object_activate+0x10b/0x4c0 lib/debugobjects.c:814
 debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
 __call_rcu_common.constprop.0+0x35/0xa10 kernel/rcu/tree.c:3104
 call_rcu_hurry include/linux/rcupdate.h:115 [inline]
 dst_release net/core/dst.c:177 [inline]
 dst_release+0x266/0x340 net/core/dst.c:165
 refdst_drop include/net/dst.h:266 [inline]
 skb_dst_drop include/net/dst.h:278 [inline]
 skb_release_head_state+0x28e/0x3f0 net/core/skbuff.c:1156
 skb_release_all net/core/skbuff.c:1180 [inline]
 __kfree_skb net/core/skbuff.c:1196 [inline]
 consume_skb net/core/skbuff.c:1428 [inline]
 consume_skb+0x85/0x100 net/core/skbuff.c:1422
 nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:60 [inline]
 nft_synproxy_do_eval+0xa6b/0xd80 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x2e9/0x1920 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x18a/0x340 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
 nf_hook.constprop.0+0x424/0x750 include/linux/netfilter.h:273
 NF_HOOK include/linux/netfilter.h:316 [inline]
 ip_local_deliver+0x169/0x1f0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:474 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_rcv+0x2e0/0x600 net/ipv4/ip_input.c:573
 __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6137
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
 process_backlog+0x4a2/0x1650 net/core/dev.c:6602
 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
 napi_poll net/core/dev.c:7729 [inline]
 net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0xa4/0xc0 arch/x86/kernel/irq_work.c:17
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:733
RIP: 0010:finish_task_switch.isra.0+0x210/0xbd0 kernel/sched/core.c:5114
Code: ac 08 00 00 44 8b 05 a3 c6 fd 0e 45 85 c0 0f 85 be 01 00 00 4c 89 e7 e8 ae f6 ff ff e8 19 eb 3b 00 fb 65 48 8b 1d 28 92 27 12 <48> 8d bb 48 16 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc9000bef78e0 EFLAGS: 00000206
RAX: 000000000014c071 RBX: ffff88807599a4c0 RCX: 0000000000000007
RDX: 0000000000000000 RSI: ffffffff8dacde18 RDI: ffffffff8bf2b380
RBP: ffffc9000bef7928 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff9088b3d7 R11: ffff88807599aff0 R12: ffff8880b853ac80
R13: ffff88805d55c980 R14: ffff88805d55c980 R15: ffff8880b853bab0
 context_switch kernel/sched/core.c:5259 [inline]
 __schedule+0x1141/0x6150 kernel/sched/core.c:6863
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __local_bh_enable_ip+0x107/0x120 kernel/softirq.c:457
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 cfg80211_mlme_unregister_socket+0x270/0x6b0 net/wireless/mlme.c:778
 nl80211_netlink_notify net/wireless/nl80211.c:21505 [inline]
 nl80211_netlink_notify+0x347/0x970 net/wireless/nl80211.c:21477
 notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:85
 blocking_notifier_call_chain kernel/notifier.c:380 [inline]
 blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368
 netlink_release+0x1671/0x2000 net/netlink/af_netlink.c:761
 __sock_release+0xb3/0x270 net/socket.c:662
 sock_close+0x1c/0x30 net/socket.c:1455
 __fput+0x402/0xb70 fs/file_table.c:468
 fput_close_sync+0x118/0x260 fs/file_table.c:573
 __do_sys_close fs/open.c:1573 [inline]
 __se_sys_close fs/open.c:1558 [inline]
 __x64_sys_close+0x8b/0x120 fs/open.c:1558
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6cf918e3aa
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007f6cfa0c0f90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000025 RCX: 00007f6cf918e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 0000000000000007 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f6cf93e6218 R14: 00007f6cf93e6180 R15: 00007ffea8807008
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/20 17:22 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ip_rcv
2025/08/02 13:13 upstream a6923c06a3b2 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ip_rcv
2025/10/19 22:14 upstream d9043c79ba68 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root BUG: soft lockup in ip_rcv
* Struck through repros no longer work on HEAD.