device syzkaller0 entered promiscuous mode
============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.4.471/6364 is trying to acquire lock:
ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: spin_lock include/linux/spinlock.h:364 [inline]
ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3924 [inline]
ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: __dev_queue_xmit+0xa2b/0x2e50 net/core/dev.c:4266

but task is already holding lock:
ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: spin_lock include/linux/spinlock.h:364 [inline]
ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3924 [inline]
ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: __dev_queue_xmit+0xa2b/0x2e50 net/core/dev.c:4266

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&sch->q.lock);
  lock(&sch->q.lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz.4.471/6364:
 #0: ffffffff8c31efc0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
 #1: ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: spin_lock include/linux/spinlock.h:364 [inline]
 #1: ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3924 [inline]
 #1: ffff88807a7f0108 (&sch->q.lock){+...}-{2:2}, at: __dev_queue_xmit+0xa2b/0x2e50 net/core/dev.c:4266
 #2: ffffffff8c31efc0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313

stack backtrace:
CPU: 1 PID: 6364 Comm: syz.4.471 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 __lock_acquire+0x1247/0x7b50 kernel/locking/lockdep.c:-1
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:364 [inline]
 __dev_xmit_skb net/core/dev.c:3924 [inline]
 __dev_queue_xmit+0xa2b/0x2e50 net/core/dev.c:4266
 sch_frag_xmit_hook+0x2d8/0x1be0 net/sched/sch_frag.c:147
 tcf_mirred_forward net/sched/act_mirred.c:216 [inline]
 tcf_mirred_act+0xc5a/0x1640 net/sched/act_mirred.c:322
 tcf_action_exec+0x177/0x570 net/sched/act_api.c:761
 tcf_exts_exec include/net/pkt_cls.h:315 [inline]
 basic_classify+0x1ae/0x2c0 net/sched/cls_basic.c:52
 __tcf_classify net/sched/cls_api.c:1550 [inline]
 tcf_classify+0x218/0xad0 net/sched/cls_api.c:1616
 qfq_classify net/sched/sch_qfq.c:721 [inline]
 qfq_enqueue+0x31b/0x1310 net/sched/sch_qfq.c:1245
 dev_qdisc_enqueue+0x48/0x210 net/core/dev.c:3865
 __dev_xmit_skb net/core/dev.c:3949 [inline]
 __dev_queue_xmit+0xbde/0x2e50 net/core/dev.c:4266
 packet_snd net/packet/af_packet.c:3119 [inline]
 packet_sendmsg+0x3b4f/0x4de0 net/packet/af_packet.c:3150
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5be/0x8f0 net/socket.c:2446
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2500
 __sys_sendmsg net/socket.c:2529 [inline]
 __do_sys_sendmsg net/socket.c:2538 [inline]
 __se_sys_sendmsg+0x1b7/0x2a0 net/socket.c:2536
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcca10e30d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcc9f33b028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fcca136afa0 RCX: 00007fcca10e30d9
RDX: 0000000000004005 RSI: 0000200000000280 RDI: 0000000000000006
RBP: 00007fcca117a024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcca136b038 R14: 00007fcca136afa0 R15: 00007fff8bc3fe98
 </TASK>