rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10499 ticks this GP) idle=bd6c/1/0x4000000000000000 softirq=150094/150094 fqs=5223
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:     6913          0            0
rcu: 	cputime:      304          0        52185   ==> 52490(ms)
rcu: 	(t=10500 jiffies g=107993 q=2615 ncpus=2)
CPU: 0 UID: 0 PID: 28348 Comm: syz.2.5930 Not tainted syzkaller #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:check_preemption_disabled+0x12/0x120
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 be 2e 26 07 <48> 89 44 24 08 65 8b 05 c6 2e 26 07 65 8b 0d bb 2e 26 07 f7 c1 ff
RSP: 0018:ffffc9000307eea8 EFLAGS: 00000282
RAX: be885efb8a5e7600 RBX: 0000000000000000 RCX: ffff888049365640
RDX: ffff888049365640 RSI: ffffffff8be33860 RDI: ffffffff8be33820
RBP: 0000000000000001 R08: ffff888049365640 R09: 0000000000000002
R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8881182e7838
R13: dffffc0000000000 R14: ffff888046c1f000 R15: ffff8880204ca478
FS:  00007f21969796c0(0000) GS:ffff8880b8614000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001200 CR3: 0000000110174000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 rcu_is_watching+0x15/0xb0
 rcu_read_lock_held+0x15/0x50
 qdisc_lookup_rcu+0x381/0x6d0
 qdisc_tree_reduce_backlog+0x1b2/0x480
 fq_change+0xeba/0x2030
 fq_init+0x699/0x960
 qdisc_create+0x7ac/0xea0
 tc_modify_qdisc+0x1538/0x20e0
 rtnetlink_rcv_msg+0x77c/0xb70
 netlink_rcv_skb+0x208/0x470
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2195b8ebe9
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:00007f2196979038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2195dc5fa0 RCX: 00007f2195b8ebe9
RDX: 0000000000000000 RSI: 0000200000001200 RDI: 0000000000000005
RBP: 00007f2195c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2195dc6038 R14: 00007f2195dc5fa0 R15: 00007ffc0f199b78
 </TASK>
