rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=6b94/1/0x4000000000000000 softirq=87658/87662 fqs=2825
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:     5248          0            0
rcu: 	cputime:      241          0        52187   ==> 52440(ms)
rcu: 	(t=10501 jiffies g=53461 q=2574 ncpus=2)
CPU: 1 UID: 0 PID: 14776 Comm: syz.3.2739 Not tainted 6.16.0-rc3-syzkaller-00159-g223e2288f4b8 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:debug_smp_processor_id+0x0/0x20
Code: c7 60 a9 1f 8e 4c 89 f6 e8 2d 00 88 f9 e9 66 ff ff ff cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 c7 c7 60 8f e2 8b 48 c7 c6 a0 8f e2 8b eb 1c 66 66
RSP: 0018:ffffc90003966f38 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000201
RDX: ffff888106e8d640 RSI: ffffffff8be28fa0 RDI: ffffffff8be28f60
RBP: 0000000000000001 R08: ffff888106e8d640 R09: 0000000000000002
R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8880364ac038
R13: dffffc0000000000 R14: ffff888124ed8800 R15: ffff88802ecc8478
FS:  00007f772ed6f6c0(0000) GS:ffff8881a3c1d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc9296e1690 CR3: 00000001066a6000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rcu_lockdep_current_cpu_online+0x37/0x120
 rcu_read_lock_held+0x1e/0x50
 qdisc_lookup_rcu+0x381/0x6d0
 qdisc_tree_reduce_backlog+0x1b2/0x480
 fq_codel_change+0xa96/0xef0
 fq_codel_init+0x355/0x960
 qdisc_create+0x7ac/0xea0
 tc_modify_qdisc+0x1426/0x2010
 rtnetlink_rcv_msg+0x77c/0xb70
 netlink_rcv_skb+0x208/0x470
 netlink_unicast+0x75b/0x8d0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x52d/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __sys_sendmmsg+0x227/0x430
 __x64_sys_sendmmsg+0xa0/0xc0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f772df8e929
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:00007f772ed6f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f772e1b5fa0 RCX: 00007f772df8e929
RDX: 040000000000009f RSI: 00002000000002c0 RDI: 0000000000000005
RBP: 00007f772e010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f772e1b5fa0 R15: 00007fff89455558
 </TASK>
