[v6.1] BUG: soft lockup in mld_ifc_work

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 76ba310227d2 Linux 6.1.32
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1089130d280000
kernel config: https://syzkaller.appspot.com/x/.config?x=3d054c5c4a3e2d63
dashboard link: https://syzkaller.appspot.com/bug?extid=1a46c68d4aa6777c6063
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e0c868320bc7/disk-76ba3102.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f7fcc207e1e7/vmlinux-76ba3102.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5ddc172b4acf/Image-76ba3102.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1a46c6...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [kworker/1:16:17021]
Modules linked in:
irq event stamp: 276413
hardirqs last enabled at (276412): [<ffff8000121071c0>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:84 [inline]
hardirqs last enabled at (276412): [<ffff8000121071c0>] exit_to_kernel_mode+0xe8/0x118 arch/arm64/kernel/entry-common.c:94
hardirqs last disabled at (276413): [<ffff800012104e9c>] __el1_irq arch/arm64/kernel/entry-common.c:468 [inline]
hardirqs last disabled at (276413): [<ffff800012104e9c>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:486
softirqs last enabled at (269998): [<ffff80001108833c>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (270000): [<ffff800010f1b6b4>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
CPU: 1 PID: 17021 Comm: kworker/1:16 Not tainted 6.1.32-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: mld mld_ifc_work
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : list_add_tail include/linux/list.h:102 [inline]
pc : list_move_tail include/linux/list.h:230 [inline]
pc : fq_pie_qdisc_dequeue+0x3ac/0x8ac net/sched/sch_fq_pie.c:248
lr : __list_del_entry include/linux/list.h:137 [inline]
lr : list_move_tail include/linux/list.h:229 [inline]
lr : fq_pie_qdisc_dequeue+0x290/0x8ac net/sched/sch_fq_pie.c:248
sp : ffff8000239970e0
x29: ffff800023997150 x28: ffff00013f210f20 x27: ffff0000d9dc3ae8
x26: ffff0000d9dc3af0 x25: dfff800000000000 x24: ffff0000d9dc3ae0
x23: ffff00013f210f10 x22: 0000000000000040 x21: ffff0000d9dc3ae0
x20: ffff0000d9dc3ae8 x19: ffff0000d9dc3ae0 x18: ffff0000d9236008
x17: 0000000000000000 x16: ffff8000084fa384 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000001 x12: ffff00012c6f5340
x11: ff80800010718f60 x10: 0000000000000000 x9 : ffff800010718f60
x8 : 0000000000000000 x7 : ffff80000840686c x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff00013f210f20 x1 : 0000000000000000 x0 : ffff00013f210f28
Call trace:
list_add_tail include/linux/list.h:102 [inline]
list_move_tail include/linux/list.h:230 [inline]
fq_pie_qdisc_dequeue+0x3ac/0x8ac net/sched/sch_fq_pie.c:248
dequeue_skb net/sched/sch_generic.c:292 [inline]
qdisc_restart net/sched/sch_generic.c:397 [inline]
__qdisc_run+0x204/0x239c net/sched/sch_generic.c:415
__dev_xmit_skb net/core/dev.c:3885 [inline]
__dev_queue_xmit+0xe14/0x38d8 net/core/dev.c:4227
dev_queue_xmit include/linux/netdevice.h:3018 [inline]
neigh_connected_output+0x2f8/0x38c net/core/neighbour.c:1612
neigh_output include/net/neighbour.h:546 [inline]
ip6_finish_output2+0xdb4/0x1a98 net/ipv6/ip6_output.c:134
__ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
ip6_finish_output+0x538/0x8c8 net/ipv6/ip6_output.c:206
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip6_output+0x270/0x594 net/ipv6/ip6_output.c:227
dst_output include/net/dst.h:444 [inline]
NF_HOOK+0x160/0x4f0 include/linux/netfilter.h:302
mld_sendpack+0x904/0x1358 net/ipv6/mcast.c:1820
mld_send_cr net/ipv6/mcast.c:2121 [inline]
mld_ifc_work+0x848/0xc20 net/ipv6/mcast.c:2653
process_one_work+0x7ac/0x1404 kernel/workqueue.c:2289
worker_thread+0x8e4/0xfec kernel/workqueue.c:2436
kthread+0x250/0x2d8 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.