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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: 4d15h, last: 12h49m
▶ ▼ 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 1529d 1530d 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 521d 521d 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 658d 713d 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 674d 674d 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 173d 253d 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 4d22h 942d 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 1086d 1144d 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 2103d 2129d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in ip_list_rcv (4) netfilter 1 1 1461d 1461d 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 1957d 2036d 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 293d 293d 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 1649d 1649d 0/29 closed as invalid on 2022/02/08 10:10
linux-6.6 INFO: rcu detected stall in ip_list_rcv 1 7 20h52m 212d 0/2 upstream: reported on 2025/12/04 02:09
android-5-15 BUG: soft lockup in ip_list_rcv 1 20 648d 801d 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 700d 722d 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 464d 464d 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 696d 696d 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: { 0-.... } 2873 jiffies s: 5293 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4685 Comm: syz.6.31 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 db d5 06 03 31 c0
RSP: 0018:ffffc90000006778 EFLAGS: 00000006
RAX: 000000600c7e1f72 RBX: ffff8880b8e27280 RCX: 00000000000006e0
RDX: 0000000000000060 RSI: ffff8880b8e27280 RDI: 00000000000002f4
RBP: 0000000000000000 R08: ffffffff8e2123ef R09: 1ffffffff1c4247d
R10: dffffc0000000000 R11: fffffbfff1c4247e R12: dffffc0000000000
R13: 00000000008cccc4 R14: 00000000000002f4 R15: 0000000000000019
FS:  00007f26527846c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdefa6f5d58 CR3: 000000007f624000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
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:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:215
Code: 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 10 05 9f 0c 48 89 de 5b e9 77 5d 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 24 4e 80 7e 65 8b 15 25 4e 80 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc900000069b8 EFLAGS: 00000246
RAX: ffffffff88bdfffb RBX: ffffc90000006b60 RCX: 0000000000000100
RDX: ffff88802e179e00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88802f5e9920 R08: ffff88807dda8e53 R09: 1ffff1100fbb51ca
R10: dffffc0000000000 R11: ffffed100fbb51cb R12: dffffc0000000000
R13: 0000000000000002 R14: ffff88807dda95ae R15: 000000000000ef5f
 tcp_options_write+0x6b/0xc70 net/ipv4/tcp_output.c:614
 __tcp_transmit_skb+0x1427/0x31e0 net/ipv4/tcp_output.c:1360
 tcp_validate_incoming+0x141f/0x2160 net/ipv4/tcp_input.c:5878
 tcp_rcv_state_process+0x871/0x42f0 net/ipv4/tcp_input.c:6629
 tcp_v4_do_rcv+0x362/0xaf0 net/ipv4/tcp_ipv4.c:1707
 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:rcu_lockdep_current_cpu_online+0x5c/0x120 kernel/rcu/tree.c:768
Code: 08 89 c3 83 f8 08 0f 83 c2 00 00 00 49 be 00 00 00 00 00 fc ff df 48 8d 1c dd 80 f9 65 8c 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 ea 24 67 00 48 8b 03 48 8d 98 c0 bb 03 00 48 8d
RSP: 0018:ffffc90003747530 EFLAGS: 00000246
RAX: 1ffffffff18cbf30 RBX: ffffffff8c65f980 RCX: e6a71f63704ee400
RDX: ffff88802e179e00 RSI: ffffffff8adf4140 RDI: ffffffff8adf4100
RBP: ffffc90003747658 R08: dffffc0000000000 R09: 1ffffffff2162048
R10: dffffc0000000000 R11: fffffbfff2162049 R12: ffffffff8c9f9a20
R13: 1ffff920006e8eb8 R14: dffffc0000000000 R15: 0000000000000000
 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline]
 rcu_read_lock_held+0x1a/0x40 kernel/rcu/update.c:309
 bpf_prog_run_array include/linux/bpf.h:1658 [inline]
 trace_call_bpf+0x1f2/0x6b0 kernel/trace/bpf_trace.c:135
 perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:10027
 perf_trace_lock_acquire+0x342/0x3f0 include/trace/events/lock.h:24
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x452/0x4a0 kernel/locking/lockdep.c:5633
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735
 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+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_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc_lru+0x182/0x2e0 mm/slub.c:3390
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 sock_alloc_inode+0x24/0xc0 net/socket.c:306
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063
 sock_alloc net/socket.c:631 [inline]
 __sock_create+0x129/0x940 net/socket.c:1514
 sock_create net/socket.c:1606 [inline]
 __sys_socket_create net/socket.c:1643 [inline]
 __sys_socket+0xc4/0x190 net/socket.c:1671
 __do_sys_socket net/socket.c:1684 [inline]
 __se_sys_socket net/socket.c:1682 [inline]
 __x64_sys_socket+0x76/0x80 net/socket.c:1682
 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: 0033:0x7f265199de59
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:00007f2652784028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f2651c25fa0 RCX: 00007f265199de59
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 000000000000000a
RBP: 00007f2651a33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2651c26038 R14: 00007f2651c25fa0 R15: 00007ffe7b97e308
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.