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INFO: rcu detected stall in ip_list_rcv (4)

Status: upstream: reported on 2026/06/29 13:08
Reported-by: syzbot+d048b6277c10563ef2c6@syzkaller.appspotmail.com
First crash: 9d18h, last: 3d04h
▶ ▼ 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 1534d 1535d 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 526d 526d 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 663d 719d 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 679d 679d 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 178d 258d 0/3 auto-obsoleted due to no activity on 2026/04/21 10:23
upstream INFO: rcu detected stall in ip_list_rcv (6) prio:low net 1 C done done 59 10d 947d 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 1091d 1149d 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 2108d 2134d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in ip_list_rcv (4) netfilter 1 1 1466d 1466d 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 1962d 2041d 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 298d 298d 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 1654d 1654d 0/29 closed as invalid on 2022/02/08 10:10
linux-6.6 INFO: rcu detected stall in ip_list_rcv 1 7 6d00h 217d 0/2 upstream: reported on 2025/12/04 02:09
android-5-15 BUG: soft lockup in ip_list_rcv 1 20 653d 806d 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 705d 728d 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 469d 469d 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 701d 701d 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: { 1-.... } 5963 jiffies s: 6305 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: 4740 Comm: syz.0.149 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsrl arch/x86/include/asm/msr.h:262 [inline]
RIP: 0010:lapic_next_deadline+0x21/0x40 arch/x86/kernel/apic/apic.c:491
Code: 5b 41 5c 41 5e 41 5f 5d c3 0f ae f0 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 48 8d 04 fa 48 89 c2 48 c1 ea 20 b9 e0 06 00 00 0f 30 <66> 90 31 c0 c3 bf e0 06 00 00 48 89 c6 31 d2 e8 3b e6 06 03 31 c0
RSP: 0018:ffffc900001debe8 EFLAGS: 00000007
RAX: 00000059e76665f9 RBX: ffff8880b8f27280 RCX: 00000000000006e0
RDX: 0000000000000059 RSI: ffff8880b8f27280 RDI: 00000000000007ec
RBP: 0000000000000000 R08: ffffffff8e2121af R09: 1ffffffff1c42435
R10: dffffc0000000000 R11: fffffbfff1c42436 R12: dffffc0000000000
R13: 00000000008cccc4 R14: 00000000000007ec R15: 0000000000000019
FS:  00007fa83952b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f912ab556b8 CR3: 00000000254ea000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334
 hrtimer_interrupt+0x561/0x980 kernel/time/hrtimer.c:1890
 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:__orc_find arch/x86/kernel/unwind_orc.c:50 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x11e0/0x1fd0 arch/x86/kernel/unwind_orc.c:448
Code: 00 0f 85 7d 05 00 00 c6 05 40 97 d3 0c 01 48 c7 c7 00 8a 89 8a 48 8b 74 24 48 e8 8d 0d ec 08 e9 60 05 00 00 49 89 f4 48 89 f5 <4c> 89 e8 48 29 e8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83
RSP: 0018:ffffc900001dee20 EFLAGS: 00000293
RAX: ffffffff8e30e320 RBX: ffffc900001deec8 RCX: ffffffff8e30e328
RDX: ffffffff8ea0b3d8 RSI: ffffffff8e30e310 RDI: 0000000000000001
RBP: ffffffff8e30e328 R08: 000000000000000c R09: 0000000000000020
R10: dffffc0000000000 R11: fffff5200003bde5 R12: ffffffff8e30e324
R13: ffffffff8e30e33c R14: ffffffff814f4874 R15: ffffffff8e30e324
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x2a0 mm/slub.c:3709
 packet_rcv+0x166/0x1300 net/packet/af_packet.c:2280
 dev_queue_xmit_nit+0xb0c/0xba0 net/core/dev.c:2366
 xmit_one net/core/dev.c:3691 [inline]
 dev_hard_start_xmit+0x158/0x8b0 net/core/dev.c:3711
 sch_direct_xmit+0x24d/0x4a0 net/sched/sch_generic.c:345
 __dev_xmit_skb net/core/dev.c:3932 [inline]
 __dev_queue_xmit+0x180d/0x3810 net/core/dev.c:4337
 neigh_output include/net/neighbour.h:545 [inline]
 ip_finish_output2+0xd53/0x1220 net/ipv4/ip_output.c:228
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip_output+0x2d9/0x400 net/ipv4/ip_output.c:434
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0x10e6/0x1c10 net/ipv4/ip_output.c:538
 __tcp_transmit_skb+0x1cc4/0x31e0 net/ipv4/tcp_output.c:1407
 tcp_validate_incoming+0xe6f/0x2160 net/ipv4/tcp_input.c:5834
 tcp_rcv_established+0x8bf/0x1de0 net/ipv4/tcp_input.c:6100
 tcp_v4_do_rcv+0x67c/0xaf0 net/ipv4/tcp_ipv4.c:1684
 tcp_v4_rcv+0x2810/0x2e90 net/ipv4/tcp_ipv4.c:2115
 ip_protocol_deliver_rcu+0x38c/0x740 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2c0/0x510 net/ipv4/ip_input.c:233
 NF_HOOK+0x329/0x3b0 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+0xa2e/0xd50 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3e9/0x440 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5662 [inline]
 __netif_receive_skb_list_core+0x57e/0x770 net/core/dev.c:5710
 __netif_receive_skb_list net/core/dev.c:5762 [inline]
 netif_receive_skb_list_internal+0x93f/0xca0 net/core/dev.c:5853
 gro_normal_list include/net/gro.h:433 [inline]
 gro_normal_one include/net/gro.h:446 [inline]
 napi_skb_finish net/core/gro.c:633 [inline]
 napi_gro_receive+0x4eb/0xb50 net/core/gro.c:663
 receive_buf+0x1ac0/0x4e40 drivers/net/virtio_net.c:1327
 virtnet_receive drivers/net/virtio_net.c:1592 [inline]
 virtnet_poll+0x5c9/0x1150 drivers/net/virtio_net.c:1710
 __napi_poll+0xbb/0x460 net/core/dev.c:6628
 napi_poll net/core/dev.c:6695 [inline]
 net_rx_action+0x622/0xbc0 net/core/dev.c:6809
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 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:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6874
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 b5 cf 1f f7 e8 b0 99 4f f7 fb bf 01 00 00 00 <e8> 25 ba ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc900049cf260 EFLAGS: 00000286
RAX: 9a3eddf089fd3e00 RBX: 0000000000000000 RCX: 9a3eddf089fd3e00
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: 0000000000000001
RBP: ffffc900049cf310 R08: ffffffff90b10277 R09: 1ffffffff216204e
R10: dffffc0000000000 R11: fffffbfff216204f R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000939e4c
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:pmd_page_vaddr arch/x86/include/asm/pgtable.h:799 [inline]
RIP: 0010:pte_offset_kernel include/linux/pgtable.h:92 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1415 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1572 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1601 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1622 [inline]
RIP: 0010:unmap_page_range+0x968/0x25b0 mm/memory.c:1643
Code: ee 06 48 b8 00 00 00 00 00 ea ff ff 4e 8d 74 30 28 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 ab 4c 14 00 49 8b 3e <49> 21 df 48 8b 1c 24 41 89 de 41 c1 ee 09 41 81 e6 f8 0f 00 00 48
RSP: 0018:ffffc900049cf3d0 EFLAGS: 00000246
RAX: 1ffffd40003eda25 RBX: 000000007db44067 RCX: ffff88801b3a5a00
RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff88802ea6d720
RBP: ffffc900049cf510 R08: ffffc900049cf4cf R09: ffffc900049cf4c0
R10: dffffc0000000000 R11: fffff52000939e9a R12: ffffc900049cf700
R13: dffffc0000000000 R14: ffffea0001f6d128 R15: 000ffffffffff000
 unmap_vmas+0x260/0x390 mm/memory.c:1728
 exit_mmap+0x20d/0x970 mm/mmap.c:3250
 __mmput+0x118/0x3a0 kernel/fork.c:1206
 mmput kernel/fork.c:1228 [inline]
 dup_mm kernel/fork.c:1563 [inline]
 copy_mm+0x1414/0x1680 kernel/fork.c:1596
 copy_process+0x19a6/0x40c0 kernel/fork.c:2357
 kernel_clone+0x24b/0x900 kernel/fork.c:2764
 __do_sys_clone kernel/fork.c:2905 [inline]
 __se_sys_clone kernel/fork.c:2889 [inline]
 __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2889
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa83859de59
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:00007fa83952afd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fa838825fa0 RCX: 00007fa83859de59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000081084000
RBP: 00007fa838633e6f R08: 0000200000002380 R09: 0000200000002380
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fa838826038 R14: 00007fa838825fa0 R15: 00007fff0ac05138
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/06 03:19 linux-6.1.y 090666d3cc90 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in ip_list_rcv
2026/07/05 11:47 linux-6.1.y 090666d3cc90 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in ip_list_rcv
2026/07/03 15:24 linux-6.1.y fdb6fcb41cc7 58bf2096 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in ip_list_rcv
2026/06/29 13:07 linux-6.1.y fdb6fcb41cc7 6a0c72dc .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.