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INFO: rcu detected stall in hsr_announce (2)

Status: upstream: reported on 2025/11/02 16:52
Reported-by: syzbot+f23711a3e0b0cf750d6e@syzkaller.appspotmail.com
First crash: 50d, last: 24d
▶ ▼ Similar bugs (16)
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 375d 475d 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 2211d 2211d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in hsr_announce (5) net 1 4 1498d 1511d 0/29 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in hsr_announce (6) kvm 1 2 1337d 1337d 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 1998d 2197d 0/1 upstream: reported C repro on 2019/12/17 23:42
upstream INFO: rcu detected stall in hsr_announce (4) net 1 1 1837d 1837d 0/29 auto-closed as invalid on 2021/03/11 15:56
upstream INFO: rcu detected stall in hsr_announce net 1 1 2291d 2291d 0/29 auto-closed as invalid on 2019/11/13 18:24
linux-6.6 INFO: rcu detected stall in hsr_announce 1 1 7d03h 7d03h 0/2 upstream: reported on 2025/12/16 05:20
upstream INFO: rcu detected stall in hsr_announce (2) net 1 3 2215d 2215d 0/29 closed as invalid on 2019/11/29 14:24
upstream INFO: rcu detected stall in hsr_announce (7) net 1 30 315d 315d 0/29 closed as invalid on 2025/03/17 11:18
linux-5.15 INFO: rcu detected stall in hsr_announce (2) 1 1 124d 124d 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 448d 494d 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 1911d 1911d 0/1 auto-closed as invalid on 2021/01/27 07:34
linux-4.19 BUG: soft lockup in hsr_announce (2) 1 7 1161d 1616d 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 816d 825d 0/29 auto-obsoleted due to no activity on 2023/12/27 12:08
upstream BUG: soft lockup in hsr_announce (3) net 1 20 8d03h 244d 0/29 upstream: reported on 2025/04/23 07:51

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2672 jiffies s: 316361 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: 31649 Comm: syz.6.6990 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x62/0x290 mm/kasan/generic.c:189
Code: ff df 49 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce <49> 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41
RSP: 0018:ffffc900001e0040 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 1ffffffff215c449 RCX: ffffffff81631055
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90ae2248
RBP: ffffc900001e02b0 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c44a R11: 1ffffffff215c449 R12: 00000000c17b0293
R13: 00000000c2fbef46 R14: 0000000000000001 R15: dffffc0000000001
FS:  00007f4f01e0b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd24e7f5f98 CR3: 0000000077aa5000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 __lock_acquire+0x12e5/0x7c50 kernel/locking/lockdep.c:5046
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 seqcount_lockdep_reader_access+0xc6/0x1c0 include/linux/seqlock.h:102
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get_update_offsets_now+0x95/0x3e0 kernel/time/timekeeping.c:2320
 hrtimer_update_base kernel/time/hrtimer.c:659 [inline]
 hrtimer_interrupt+0x5d9/0x9c0 kernel/time/hrtimer.c:1905
 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 ce 48 65 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f6 cd 35 f7 65 8b 05 77 85 e0 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900001e0740 EFLAGS: 00000206
RAX: e51cd90dcb40aa00 RBX: 0000000000000a06 RCX: e51cd90dcb40aa00
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001
RBP: ffffc900001e07c0 R08: dffffc0000000000 R09: fffffbfff215c466
R10: fffffbfff215c466 R11: 1ffffffff215c465 R12: dffffc0000000000
R13: ffff88807e09b8c0 R14: ffffffff96df6e78 R15: 1ffff9200003c0e8
 __debug_check_no_obj_freed lib/debugobjects.c:988 [inline]
 debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1009
 slab_free_hook mm/slub.c:1704 [inline]
 slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x290 mm/slub.c:3709
 kfree_skb include/linux/skbuff.h:1220 [inline]
 hsr_forward_skb+0x84c/0x20d0 net/hsr/hsr_forward.c:-1
 send_hsr_supervision_frame+0x4de/0xa60 net/hsr/hsr_device.c:343
 hsr_announce+0x18e/0x340 net/hsr/hsr_device.c:399
 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x529/0x7d0 kernel/time/timer.c:2022
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2035
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 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:finish_task_switch+0x26a/0x8f0 kernel/sched/core.c:5123
Code: 0f 84 3b 01 00 00 48 85 db 0f 85 5a 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 e0 6d c9 08 e8 6b b7 2e 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90003ae76f8 EFLAGS: 00000282
RAX: e51cd90dcb40aa00 RBX: 0000000000000000 RCX: e51cd90dcb40aa00
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: ffffffff8adef760
RBP: ffffc90003ae7750 R08: dffffc0000000000 R09: fffffbfff215c46d
R10: fffffbfff215c46d R11: 1ffffffff215c46c R12: ffff888048e6d940
R13: dffffc0000000000 R14: ffff88801ea95940 R15: ffff8880b8f3b590
 context_switch kernel/sched/core.c:5247 [inline]
 __schedule+0x10f4/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 fasync_insert_entry+0x1e1/0x260 fs/fcntl.c:928
 fasync_add_entry fs/fcntl.c:951 [inline]
 fasync_helper+0x4e/0xa0 fs/fcntl.c:969
 perf_fasync+0x7e/0xa0 kernel/events/core.c:6540
 ioctl_fioasync fs/ioctl.c:379 [inline]
 do_vfs_ioctl+0x1083/0x1d10 fs/ioctl.c:791
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x83/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4f00f8f749
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:00007f4f01e0b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4f011e5fa0 RCX: 00007f4f00f8f749
RDX: 00002000000006c0 RSI: 0000000000005452 RDI: 0000000000000009
RBP: 00007f4f01013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4f011e6038 R14: 00007f4f011e5fa0 R15: 00007ffc2d306108
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/29 02:55 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in hsr_announce
2025/11/02 16:52 linux-6.1.y f6e38ae624cf 2c50b6a9 .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.