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INFO: rcu detected stall in neigh_timer_handler (2)

Status: auto-obsoleted due to no activity on 2025/05/14 07:23
Reported-by: syzbot+e732965c48dcbd6783c3@syzkaller.appspotmail.com
First crash: 276d, last: 276d
▶ ▼ Similar bugs (21)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in neigh_timer_handler (6) netfilter 1 1 1793d 1793d 0/29 auto-closed as invalid on 2021/03/09 03:20
upstream INFO: rcu detected stall in neigh_timer_handler (8) net 1 C done done 72 452d 511d 28/29 fixed on 2024/10/21 12:45
upstream INFO: rcu detected stall in neigh_timer_handler net 1 1 2539d 2539d 0/29 auto-closed as invalid on 2019/05/23 06:47
upstream INFO: rcu detected stall in neigh_timer_handler (2) net 1 2 2248d 2250d 13/29 fixed on 2019/10/09 10:54
upstream INFO: rcu detected stall in neigh_timer_handler (4) net 1 1 2164d 2164d 0/29 closed as invalid on 2019/12/04 14:04
linux-5.15 INFO: rcu detected stall in neigh_timer_handler 1 1 53d 53d 0/3 upstream: reported on 2025/09/14 11:36
upstream INFO: rcu detected stall in neigh_timer_handler (5) net 1 1 1896d 1896d 0/29 auto-closed as invalid on 2020/11/26 10:25
upstream INFO: rcu detected stall in neigh_timer_handler (3) net 1 2 2169d 2169d 0/29 closed as invalid on 2019/11/29 14:24
linux-6.1 INFO: rcu detected stall in neigh_timer_handler (3) 1 1 22d 22d 0/3 upstream: reported on 2025/10/15 04:30
upstream INFO: rcu detected stall in neigh_timer_handler (7) net 1 1 1668d 1668d 0/29 auto-closed as invalid on 2021/07/11 19:14
linux-4.14 INFO: rcu detected stall in neigh_timer_handler 1 5 2014d 2133d 0/1 auto-closed as invalid on 2020/08/30 16:21
linux-6.1 INFO: rcu detected stall in neigh_timer_handler 1 4 407d 517d 0/3 auto-obsoleted due to no activity on 2025/01/03 05:12
upstream BUG: soft lockup in neigh_timer_handler (2) net 1 2 287d 317d 0/29 closed as invalid on 2025/02/28 15:46
android-5-10 BUG: soft lockup in neigh_timer_handler 1 2 805d 813d 0/2 auto-obsoleted due to no activity on 2023/11/22 05:43
linux-4.19 BUG: soft lockup in neigh_timer_handler 1 4 1090d 1349d 0/1 auto-obsoleted due to no activity on 2023/03/12 06:57
android-54 BUG: soft lockup in neigh_timer_handler (2) 1 5 175d 260d 0/2 auto-obsoleted due to no activity on 2025/08/13 05:16
linux-4.14 BUG: soft lockup in neigh_timer_handler 1 3 1358d 1402d 0/1 auto-closed as invalid on 2022/06/16 21:59
upstream BUG: soft lockup in neigh_timer_handler (3) batman 1 2 186d 187d 0/29 auto-obsoleted due to no activity on 2025/08/01 18:42
android-6-1 BUG: soft lockup in neigh_timer_handler 1 2 719d 741d 0/2 auto-obsoleted due to no activity on 2024/02/16 02:11
android-54 BUG: soft lockup in neigh_timer_handler 1 3 504d 515d 0/2 auto-obsoleted due to no activity on 2024/09/18 13:19
upstream BUG: soft lockup in neigh_timer_handler net 1 1 837d 812d 0/29 auto-obsoleted due to no activity on 2023/10/20 21:15

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2684 jiffies s: 12545 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: 5355 Comm: syz.8.174 Not tainted 6.1.128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
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:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <eb> 01 c3 89 f6 31 d2 e9 1f a4 34 03 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000006f00 EFLAGS: 00000046
RAX: 00000000000000cb RBX: ffffffff8cda7b30 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 00000000000000cb RDI: 0000000000000838
RBP: 00000000000000cb R08: ffffffff817ce0dd R09: fffffbfff1d36536
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b8e271c0
R13: dffffc0000000000 R14: 00000000000000cb R15: dffffc0000000000
FS:  00007f0494bd06c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3080fff8 CR3: 0000000060e5e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 apic_write arch/x86/include/asm/apic.h:394 [inline]
 lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:478
 clockevents_program_event+0x1c5/0x310 kernel/time/clockevents.c:334
 hrtimer_interrupt+0x546/0x980 kernel/time/hrtimer.c:1828
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 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:rcu_read_unlock_special+0x84/0x540 kernel/rcu/tree_plugin.h:682
Code: f1 f1 f1 00 f2 f2 f2 49 89 04 17 66 41 c7 44 17 09 f3 f3 41 c6 44 17 0b f3 65 44 8b 25 ad 18 8e 7e 41 f7 c4 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 3a 00 00 00 00 66 42 c7 44 3a
RSP: 0018:ffffc90000007160 EFLAGS: 00000206
RAX: 5ee5c4de51256a00 RBX: 1ffff92000000e34 RCX: ffffffff816b127a
RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: ffffffff8b5e6980
RBP: ffffc90000007238 R08: dffffc0000000000 R09: fffffbfff224a06e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8d32ff00
R13: ffff888026958458 R14: ffffc900000071a0 R15: 1ffff92000000e30
 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 batadv_choose_next_candidate net/batman-adv/distributed-arp-table.c:601 [inline]
 batadv_dat_select_candidates net/batman-adv/distributed-arp-table.c:654 [inline]
 batadv_dat_forward_data+0xab5/0x1040 net/batman-adv/distributed-arp-table.c:685
 batadv_interface_tx+0xecf/0x1750 net/batman-adv/soft-interface.c:330
 __netdev_start_xmit include/linux/netdevice.h:4888 [inline]
 netdev_start_xmit include/linux/netdevice.h:4902 [inline]
 xmit_one net/core/dev.c:3627 [inline]
 dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3643
 __dev_queue_xmit+0x1b5d/0x3d50 net/core/dev.c:4303
 NF_HOOK+0x39d/0x450 include/linux/netfilter.h:302
 arp_solicit+0xc4d/0xe60 net/ipv4/arp.c:392
 neigh_probe net/core/neighbour.c:1075 [inline]
 neigh_timer_handler+0xa4b/0x1010 net/core/neighbour.c:1157
 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:661
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:673
 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:apparmor_capable+0x0/0x190 security/apparmor/lsm.c:182
Code: e8 65 00 4e fd 0f 0b e9 ae fa ff ff e8 39 e7 85 fd 4c 89 ef be 03 00 00 00 e8 dc c0 3f 00 e9 67 ff ff ff 0f 1f 80 00 00 00 00 <55> 41 57 41 56 41 54 53 41 89 ce 41 89 d7 48 89 fd 49 bc 00 00 00
RSP: 0018:ffffc90003d8fd10 EFLAGS: 00000246
RAX: 1ffffffff19b52be RBX: ffffffff8cda95d8 RCX: 0000000000000000
RDX: 0000000000000027 RSI: ffffffff8d1d55e0 RDI: ffff88807e657280
RBP: ffffffff8cda95f0 R08: ffffffff84077446 R09: fffffbfff1d36536
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8d1d55e0
R13: ffff88807e657280 R14: dffffc0000000000 R15: 0000000000000027
 security_capable+0x76/0xb0 security/security.c:809
 ns_capable_common kernel/capability.c:376 [inline]
 ns_capable kernel/capability.c:397 [inline]
 capable+0x69/0xe0 kernel/capability.c:450
 bpf_capable include/linux/capability.h:264 [inline]
 __sys_bpf+0x95/0x6c0 kernel/bpf/syscall.c:4977
 __do_sys_bpf kernel/bpf/syscall.c:5129 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5127 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5127
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0493d8cda9
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:00007f0494bd0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f0493fa6080 RCX: 00007f0493d8cda9
RDX: 0000000000000050 RSI: 0000000020000680 RDI: 0000000000000000
RBP: 00007f0493e0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0493fa6080 R15: 00007fff27d80d08
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/03 07:22 linux-6.1.y 0cbb5f65e52f 568559e4 .config console log report info ci2-linux-6-1-kasan-perf INFO: rcu detected stall in neigh_timer_handler
* Struck through repros no longer work on HEAD.