5.4.7: WARNING: CPU: 4 PID: 30 at kernel/rcu/tree.c:2211 rcu_core+0x3f7/0x450

[Udo van den Heuvel]

[ 1634.327038] ------------[ cut here ]------------
[ 1634.327047] WARNING: CPU: 4 PID: 30 at kernel/rcu/tree.c:2211
rcu_core+0x3f7/0x450
[ 1634.327048] Modules linked in: fuse mq_deadline xt_MASQUERADE
iptable_nat nf_nat ipt_REJECT nf_reject_ipv4 xt_u32 xt_multiport
iptable_filter nf_conntrack_netbios_ns nf_conntrack_broadcast
ip6t_REJECT nf_reject_ipv6 xt_tcpudp xt_state xt_conntrack nf_conntrack
nf_defrag_ipv6 nf_defrag_ipv4 ip6table_filter it87 ip6_tables hwmon_vid
msr cdc_acm snd_usb_audio uvcvideo videobuf2_vmalloc snd_hwdep
videobuf2_memops snd_usbmidi_lib videobuf2_v4l2 videodev
videobuf2_common snd_rawmidi snd_hda_codec_realtek snd_hda_codec_generic
snd_hda_intel snd_intel_nhlt snd_hda_codec snd_hda_core snd_seq
snd_seq_device snd_pcm bfq snd_timer snd i2c_piix4 k10temp acpi_cpufreq
evdev binfmt_misc ip_tables x_tables hid_generic sr_mod cdrom usbhid
aesni_intel amdgpu gpu_sched ttm i2c_dev autofs4
[ 1634.327079] CPU: 4 PID: 30 Comm: ksoftirqd/4 Tainted: G        W
   5.4.7 #9
[ 1634.327081] Hardware name: Gigabyte Technology Co., Ltd. X570 AORUS
PRO/X570 AORUS PRO, BIOS F11 12/06/2019
[ 1634.327084] RIP: 0010:rcu_core+0x3f7/0x450
[ 1634.327086] Code: fd ff ff 48 2b 15 49 13 f6 00 48 39 c2 7e 07 48 89
83 b0 00 00 00 48 8b 43 50 48 85 c0 75 c7 0f 0b eb c3 0f 0b e9 59 fc ff
ff <0f> 0b eb b8 48 8b 15 26 13 f6 00 48 89 93 c0 00 00 00 e9 72 ff ff
[ 1634.327088] RSP: 0018:ffff96a280203e18 EFLAGS: 00010002
[ 1634.327090] RAX: 0000017c884920cb RBX: ffff8bf51f11ee80 RCX:
ffff8bf2927e8a10
[ 1634.327092] RDX: 0000000000000000 RSI: ffff96a280203e18 RDI:
ffff8bf51f11eed0
[ 1634.327093] RBP: ffff8bf51f11eed0 R08: ffff8bf2927e8a10 R09:
0000000000000100
[ 1634.327094] R10: 0000000000000080 R11: ffff8bf51f11e278 R12:
0000000000000246
[ 1634.327095] R13: ffff8bf51df4a4c0 R14: 0000000000000000 R15:
ffffffff8d005110
[ 1634.327097] FS:  0000000000000000(0000) GS:ffff8bf51f100000(0000)
knlGS:0000000000000000
[ 1634.327099] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1634.327100] CR2: 00007f2528504000 CR3: 00000003dab80000 CR4:
00000000003406e0
[ 1634.327101] Call Trace:
[ 1634.327106]  __do_softirq+0xfc/0x247
[ 1634.327109]  run_ksoftirqd+0x21/0x30
[ 1634.327113]  smpboot_thread_fn+0x195/0x230
[ 1634.327117]  ? sort_range+0x20/0x20
[ 1634.327119]  kthread+0x118/0x130
[ 1634.327122]  ? kthread_create_worker_on_cpu+0x60/0x60
[ 1634.327124]  ret_from_fork+0x22/0x40
[ 1634.327126] ---[ end trace 30ee3be19ded2949 ]---

What happend here?
Is it a bug?

Kind regards,
Udo