============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.2.4910/25393 is trying to acquire lock:
ffff8881086de158 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: sch_direct_xmit+0x153/0x4b0

but task is already holding lock:
ffff888027c93958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: __dev_queue_xmit+0x1676/0x3b50

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

       CPU0
       ----
  lock(&qdisc_xmit_lock_key#4);
  lock(&qdisc_xmit_lock_key#4);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

6 locks held by syz.2.4910/25393:
 #0: ffffffff8e13a140 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50
 #1: ffff888027c93958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: __dev_queue_xmit+0x1676/0x3b50
 #2: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: ip_output+0x60/0x3c0
 #3: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x452/0x1160
 #4: ffffffff8e13a140 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50
 #5: ffff88802feed258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#3){+...}-{3:3}, at: __dev_queue_xmit+0x138a/0x3b50

stack backtrace:
CPU: 0 UID: 0 PID: 25393 Comm: syz.2.4910 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
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 print_deadlock_bug+0x28b/0x2a0
 validate_chain+0x1a3f/0x2140
 __lock_acquire+0xab9/0xd20
 lock_acquire+0x120/0x360
 _raw_spin_lock+0x2e/0x40
 sch_direct_xmit+0x153/0x4b0
 __dev_queue_xmit+0x1857/0x3b50
 ip_finish_output2+0xd03/0x1160
 ip_output+0x2a1/0x3c0
 iptunnel_xmit+0x592/0xa40
 ip_tunnel_xmit+0x1c41/0x2390
 ipgre_xmit+0x89e/0xc50
 dev_hard_start_xmit+0x2d7/0x830
 __dev_queue_xmit+0x1b8d/0x3b50
 packet_sendmsg+0x3e33/0x5080
 __sock_sendmsg+0x21c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f325a98eba9
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:00007f325b821038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f325abd5fa0 RCX: 00007f325a98eba9
RDX: 000000000000001a RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f325aa11e19 R08: 0000200000000040 R09: 0000000000000014
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f325abd6038 R14: 00007f325abd5fa0 R15: 00007ffd36488648
 </TASK>
