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BUG: soft lockup in garp_join_timer (4)

Status: closed as invalid on 2025/11/11 16:41
Subsystems: net
[Documentation on labels]
First crash: 44d, last: 44d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: soft lockup in garp_join_timer net 1 1 1764d 1764d 0/29 auto-closed as invalid on 2021/04/19 17:30
linux-5.15 BUG: soft lockup in garp_join_timer 1 1 794d 794d 0/3 auto-obsoleted due to no activity on 2023/12/25 14:40
upstream BUG: soft lockup in garp_join_timer (3) net 1 3 179d 211d 0/29 auto-obsoleted due to no activity on 2025/08/31 15:42
linux-4.19 BUG: soft lockup in garp_join_timer 1 19 1114d 1622d 0/1 auto-obsoleted due to no activity on 2023/03/01 00:21
upstream BUG: soft lockup in garp_join_timer (2) net 1 2 301d 319d 0/29 closed as invalid on 2025/02/20 20:55
upstream INFO: rcu detected stall in garp_join_timer (3) net 1 3 501d 571d 0/29 auto-obsoleted due to no activity on 2024/10/03 12:56
upstream INFO: rcu detected stall in garp_join_timer (2) net 1 25 1403d 2103d 0/29 auto-closed as invalid on 2022/05/15 13:33

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 128s! [syz.9.621:8532]
Modules linked in:
irq event stamp: 17683579
hardirqs last  enabled at (17683578): [<ffffffff8b34d7c4>] irqentry_exit+0x74/0x90 kernel/entry/common.c:214
hardirqs last disabled at (17683579): [<ffffffff8b34c40e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1052
softirqs last  enabled at (17660500): [<ffffffff81839b1a>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last  enabled at (17660500): [<ffffffff81839b1a>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last  enabled at (17660500): [<ffffffff81839b1a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
softirqs last disabled at (17660503): [<ffffffff81839b1a>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last disabled at (17660503): [<ffffffff81839b1a>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last disabled at (17660503): [<ffffffff81839b1a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
CPU: 0 UID: 0 PID: 8532 Comm: syz.9.621 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 ab d3 8e f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 53 5d 57 f6 65 8b 05 3c fd 11 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90000007aa0 EFLAGS: 00000206
RAX: b2ebd873c3375100 RBX: 0000000000000a02 RCX: b2ebd873c3375100
RDX: 0000000000000002 RSI: ffffffff8d512c0f RDI: 0000000000000001
RBP: ffffc90000007b20 R08: ffffffff8f5bed37 R09: 1ffffffff1eb7da6
R10: dffffc0000000000 R11: fffffbfff1eb7da7 R12: dffffc0000000000
R13: ffff888027abd410 R14: ffff888027abd4b8 R15: 1ffff92000000f54
FS:  00007f283eb826c0(0000) GS:ffff88812638a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000004 CR3: 00000000270d6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 skb_dequeue+0x10e/0x150 net/core/skbuff.c:3900
 garp_queue_xmit net/802/garp.c:272 [inline]
 garp_join_timer+0x8e/0x120 net/802/garp.c:424
 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x283/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:task_dead_fair+0x81/0x400 kernel/sched/fair.c:8663
Code: c1 ea 03 48 b8 f1 f1 f1 f1 00 00 f3 f3 48 89 54 24 18 48 89 04 0a 4c 8d a7 d1 00 00 00 4d 89 e5 49 c1 ed 03 41 0f b6 44 0d 00 <84> c0 0f 85 d4 02 00 00 4c 8d b3 80 00 00 00 41 80 3c 24 00 0f 84
RSP: 0018:ffffc9000bcb71c0 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffff8880254f5ac0 RCX: dffffc0000000000
RDX: 1ffff92001796e3c RSI: 0000000000000004 RDI: ffff8880254f5ac0
RBP: ffffc9000bcb7268 R08: ffff88807a8d35c3 R09: 1ffff1100f51a6b8
R10: dffffc0000000000 R11: ffffffff81935e50 R12: ffff8880254f5b91
R13: 1ffff11004a9eb72 R14: ffffffff8d71e2f0 R15: ffff88807a8d35c0
 finish_task_switch+0x44c/0x950 kernel/sched/core.c:5223
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x17a0/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:PagePoisoned include/linux/page-flags.h:335 [inline]
RIP: 0010:PageReserved include/linux/page-flags.h:575 [inline]
RIP: 0010:__text_poke+0x176/0xa10 arch/x86/kernel/alternative.c:2448
Code: 7b 0d 00 49 89 c7 49 c1 ef 06 49 83 e7 c0 49 01 df 4d 89 fe 49 c1 ee 03 43 80 3c 2e 00 74 08 4c 89 ff e8 3d 72 bd 00 49 8b 1f <48> c7 c7 ff ff ff ff 48 89 de e8 3b d4 57 00 48 83 fb ff 0f 84 38
RSP: 0018:ffffc9000bcb7660 EFLAGS: 00000246
RAX: 00000000019c3126 RBX: 00fff00000002000 RCX: 0000000000080000
RDX: ffffc9000ff74000 RSI: 000000000000510c RDI: 000000000000510d
RBP: ffffc9000bcb77b0 R08: 000000000000441f R09: 0000000000000006
R10: dffffc0000000000 R11: fffff52001796f0a R12: ffffffff819c3126
R13: dffffc0000000000 R14: 1ffffd400000ce18 R15: ffffea00000670c0
 text_poke arch/x86/kernel/alternative.c:2552 [inline]
 smp_text_poke_batch_finish+0x90a/0x1130 arch/x86/kernel/alternative.c:2885
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 tracepoint_add_func+0x994/0xa10 kernel/tracepoint.c:315
 tracepoint_probe_register_prio kernel/tracepoint.c:464 [inline]
 tracepoint_probe_register+0x5d/0x90 kernel/tracepoint.c:484
 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
 perf_trace_event_init+0x4e1/0x9d0 kernel/trace/trace_event_perf.c:202
 perf_trace_init+0x23d/0x2d0 kernel/trace/trace_event_perf.c:226
 perf_tp_event_init+0x8d/0x120 kernel/events/core.c:10872
 perf_try_init_event+0x17c/0x870 kernel/events/core.c:12605
 perf_init_event kernel/events/core.c:12703 [inline]
 perf_event_alloc+0x133e/0x2be0 kernel/events/core.c:12978
 __do_sys_perf_event_open kernel/events/core.c:13496 [inline]
 __se_sys_perf_event_open+0x772/0x1d70 kernel/events/core.c:13377
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f283dd8eec9
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:00007f283eb82038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f283dfe6090 RCX: 00007f283dd8eec9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000200
RBP: 00007f283de11f91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f283dfe6128 R14: 00007f283dfe6090 R15: 00007ffce2253638
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7648 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd38/0x12d0 kernel/smp.c:877
Code: 89 ee 83 e6 01 31 ff e8 96 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 41 6f 0b 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 25 6f 0b 00 eb e4 44
RSP: 0018:ffffc9000383f340 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11017108439 RCX: ffff888032859e40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000383f4c0 R08: ffffffff8f5bed37 R09: 1ffffffff1eb7da6
R10: dffffc0000000000 R11: fffffbfff1eb7da7 R12: ffff8880b88421c8
R13: dffffc0000000000 R14: ffff8880b893b200 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812648a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f706b5e6038 CR3: 000000000db36000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
 tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
 free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
 exit_mmap+0x174/0xb40 mm/mmap.c:1266
 __mmput+0x118/0x430 kernel/fork.c:1133
 exit_mm+0x1da/0x2c0 kernel/exit.c:582
 do_exit+0x648/0x2300 kernel/exit.c:954
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f12a4184fd3
Code: Unable to access opcode bytes at 0x7f12a4184fa9.
RSP: 002b:00007ffed22fff08 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000001dea RCX: 00007f12a4184fd3
RDX: 0000000040000000 RSI: 00007ffed22fff1c RDI: 00000000ffffffff
RBP: 00007ffed22fff1c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/06 05:55 bpf-next de7342228b73 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in garp_join_timer
* Struck through repros no longer work on HEAD.