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INFO: rcu detected stall in hsr_announce (3)

Status: upstream: reported on 2026/06/26 13:35
Reported-by: syzbot+e3a50322dcc0651cfbd4@syzkaller.appspotmail.com
First crash: 15d, last: 2d04h
▶ ▼ Similar bugs (19)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in hsr_announce 1 3 576d 676d 0/3 auto-obsoleted due to no activity on 2025/03/22 17:50
upstream INFO: rcu detected stall in hsr_announce (3) net 1 1 2412d 2412d 0/29 closed as invalid on 2019/12/04 14:04
linux-6.1 INFO: rcu detected stall in hsr_announce (2) 1 2 225d 251d 0/3 auto-obsoleted due to no activity on 2026/03/09 02:56
upstream INFO: rcu detected stall in hsr_announce (5) net 1 4 1699d 1712d 0/29 closed as invalid on 2022/02/08 10:00
linux-6.6 BUG: soft lockup in hsr_announce origin:lts-only 1 C 2 7d01h 44d 0/2 upstream: reported C repro on 2026/05/28 20:15
upstream INFO: rcu detected stall in hsr_announce (6) kvm 1 2 1538d 1538d 0/29 auto-closed as invalid on 2022/06/25 07:59
linux-4.14 INFO: rcu detected stall in hsr_announce 1 C error 25 2199d 2398d 0/1 upstream: reported C repro on 2019/12/17 23:42
upstream INFO: rcu detected stall in hsr_announce (4) net 1 1 2038d 2038d 0/29 auto-closed as invalid on 2021/03/11 15:56
linux-5.15 INFO: rcu detected stall in hsr_announce (3) 1 5 133d 194d 0/3 auto-obsoleted due to no activity on 2026/06/09 03:32
upstream INFO: rcu detected stall in hsr_announce net 1 1 2492d 2492d 0/29 auto-closed as invalid on 2019/11/13 18:24
linux-6.6 INFO: rcu detected stall in hsr_announce 1 1 208d 208d 0/2 auto-obsoleted due to no activity on 2026/03/26 05:20
upstream INFO: rcu detected stall in hsr_announce (2) net 1 3 2416d 2416d 0/29 closed as invalid on 2019/11/29 14:24
upstream INFO: rcu detected stall in hsr_announce (7) net 1 30 516d 516d 0/29 closed as invalid on 2025/03/17 11:18
linux-5.15 INFO: rcu detected stall in hsr_announce (2) 1 1 325d 325d 0/3 auto-obsoleted due to no activity on 2025/11/28 17:51
linux-5.15 INFO: rcu detected stall in hsr_announce 1 6 649d 695d 0/3 auto-obsoleted due to no activity on 2025/01/08 22:52
linux-4.19 INFO: rcu detected stall in hsr_announce 1 1 2112d 2112d 0/1 auto-closed as invalid on 2021/01/27 07:34
linux-4.19 BUG: soft lockup in hsr_announce (2) 1 7 1362d 1817d 0/1 auto-obsoleted due to no activity on 2023/02/15 11:56
upstream BUG: soft lockup in hsr_announce (2) net 1 3 1017d 1026d 0/29 auto-obsoleted due to no activity on 2023/12/27 12:08
upstream BUG: soft lockup in hsr_announce (3) prio:normal net 1 syz 38 14d 445d 0/29 upstream: reported syz repro on 2025/04/23 07:51

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2687 jiffies s: 7241 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: 4895 Comm: syz.9.77 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:native_apic_msr_eoi_write+0xb/0x10 arch/x86/include/asm/apic.h:212
Code: 8b 06 bf f0 03 00 00 89 de 5b 41 5e 41 5f ff e0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b9 0b 08 00 00 31 c0 31 d2 0f 30 <c3> 0f 1f 40 00 81 ff cf 00 00 00 7f 0c 83 ff 20 74 2a 83 ff 30 74
RSP: 0018:ffffc900001e0798 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8c65fb30 RCX: 000000000000080b
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000b0
RBP: 0000000000000000 R08: ffffffff8fa25048 R09: ffffffff8fa25058
R10: ffffffff8fa25050 R11: ffffffff8fa25043 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fa98291c6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555587ef0a38 CR3: 00000000646b5000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 apic_eoi arch/x86/include/asm/apic.h:399 [inline]
 ack_APIC_irq arch/x86/include/asm/apic.h:445 [inline]
 __sysvec_apic_timer_interrupt+0x81/0x5a0 arch/x86/kernel/apic/apic.c:1122
 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:hsr_register_frame_out+0x33/0x390 net/hsr/hsr_framereg.c:469
Code: 53 48 83 ec 18 89 d5 49 89 f7 49 89 fe 49 bd 00 00 00 00 00 fc ff df e8 3b 1d 74 f7 49 8d 7f 10 48 89 7c 24 10 e8 2d 61 2c 00 <49> 83 c6 20 4c 89 f3 48 c1 eb 03 42 0f b6 04 2b 84 c0 0f 85 28 02
RSP: 0018:ffffc900001e0890 EFLAGS: 00000246
RAX: fe2454793d286d00 RBX: ffff888074e1cc80 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc900001e0800
RBP: 000000000000fc31 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200003c100 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888057d79d80 R15: ffff888075e7ea00
 hsr_forward_do net/hsr/hsr_forward.c:443 [inline]
 hsr_forward_skb+0xdcb/0x20c0 net/hsr/hsr_forward.c:626
 send_hsr_supervision_frame+0x5f7/0xb90 net/hsr/hsr_device.c:346
 hsr_announce+0x194/0x340 net/hsr/hsr_device.c:402
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 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:ffffc90003c27340 EFLAGS: 00000286
RAX: fe2454793d286d00 RBX: 0000000000000000 RCX: fe2454793d286d00
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: 0000000000000001
RBP: ffffc90003c273f0 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000784e68
 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:__unwind_start+0x4f5/0x650 arch/x86/kernel/unwind_orc.c:716
Code: 46 48 8b 54 24 10 48 39 ea 0f 97 c1 48 39 c2 0f 96 c0 20 c8 3c 01 75 2f 48 8b 04 24 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <48> 8d 6b 38 74 08 48 89 ef e8 fd 25 9a 00 48 8b 44 24 08 48 39 45
RSP: 0018:ffffc90003c274b8 EFLAGS: 00000246
RAX: 1ffff92000784ea8 RBX: ffffc90003c27508 RCX: dffffc0000000000
RDX: ffffc90003c27598 RSI: ffffc90003c28000 RDI: ffffc90003c274b8
RBP: ffffc90003c20000 R08: ffffc90003c27501 R09: ffffc90003c27508
R10: dffffc0000000000 R11: fffff52000784ead R12: 1ffff92000784ea2
R13: 1ffff92000784ea3 R14: 1ffff92000784ea1 R15: ffffc90003c27518
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xda/0x140 arch/x86/kernel/stacktrace.c:24
 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_kmalloc mm/kasan/common.c:375 [inline]
 __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384
 kmalloc_node include/linux/slab.h:585 [inline]
 kzalloc_node include/linux/slab.h:710 [inline]
 __get_vm_area_node+0x122/0x330 mm/vmalloc.c:2506
 __vmalloc_node_range+0x357/0x1380 mm/vmalloc.c:3203
 __vmalloc_node mm/vmalloc.c:3308 [inline]
 __vmalloc+0x76/0x80 mm/vmalloc.c:3322
 bpf_prog_alloc_no_stats+0x37/0x3a0 kernel/bpf/core.c:92
 bpf_prog_alloc+0x1c/0x1b0 kernel/bpf/core.c:130
 bpf_prog_load+0x7d4/0x1530 kernel/bpf/syscall.c:2597
 __sys_bpf+0x5b8/0x780 kernel/bpf/syscall.c:5031
 __do_sys_bpf kernel/bpf/syscall.c:5135 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5133 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5133
 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: 0033:0x7fa98199de59
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:00007fa98291c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fa981c26090 RCX: 00007fa98199de59
RDX: 0000000000000094 RSI: 0000200000000140 RDI: 0000000000000005
RBP: 00007fa981a33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa981c26128 R14: 00007fa981c26090 R15: 00007fffa16c2478
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/10 04:45 linux-6.1.y 090666d3cc90 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in hsr_announce
2026/07/03 09:54 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 hsr_announce
2026/06/26 13:34 linux-6.1.y fdb6fcb41cc7 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in hsr_announce
* Struck through repros no longer work on HEAD.