rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=0264/1/0x4000000000000000 softirq=18955/18956 fqs=5244
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:     7988          0            0
rcu: 	cputime:      113          0        52380   ==> 52520(ms)
rcu: 	(t=10503 jiffies g=9613 q=3983 ncpus=2)
CPU: 0 UID: 0 PID: 6984 Comm: syz.1.307 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:qdisc_match_from_root net/sched/sch_api.c:271 [inline]
RIP: 0010:qdisc_lookup_rcu+0x117/0x6d0 net/sched/sch_api.c:327
Code: 0f 85 2b 05 00 00 41 8b 2c 24 89 ee 83 e6 01 31 ff e8 bd 50 3b f8 83 e5 01 0f 85 91 00 00 00 4d 8d 66 38 4c 89 e0 48 c1 e8 03 <48> b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 29 05 00 00
RSP: 0018:ffffc9001a987070 EFLAGS: 00000a02
RAX: 1ffff1100f6e4107 RBX: 00000000ffff0000 RCX: 0000000000000000
RDX: ffff88806cd51e00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88806cd51e00 R09: 0000000000000002
R10: 00000000ffffffff R11: 0000000000000000 R12: ffff88807b720838
R13: ffff888032fe8000 R14: ffff88807b720800 R15: ffff888032fe8000
FS:  00007fc8745916c0(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc874590f98 CR3: 00000000769cc000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 qdisc_tree_reduce_backlog+0x1b2/0x480 net/sched/sch_api.c:795
 hhf_change+0x805/0xb40 net/sched/sch_hhf.c:574
 hhf_init+0x213/0x950 net/sched/sch_hhf.c:599
 qdisc_create+0x7ac/0xea0 net/sched/sch_api.c:1319
 __tc_modify_qdisc net/sched/sch_api.c:1748 [inline]
 tc_modify_qdisc+0x1538/0x20e0 net/sched/sch_api.c:1812
 rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 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: 0033:0x7fc87378ebe9
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:00007fc874591038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc8739b6090 RCX: 00007fc87378ebe9
RDX: 0000000000000800 RSI: 00002000000001c0 RDI: 0000000000000009
RBP: 00007fc873811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc8739b6128 R14: 00007fc8739b6090 R15: 00007ffebc195bb8
 </TASK>