syzbot

============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
kworker/u8:7/1006 is trying to acquire lock:
ffff888060f58998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
ffff888060f58998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4809 [inline]
ffff888060f58998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: sch_direct_xmit+0x15f/0x4c0 net/sched/sch_generic.c:370

but task is already holding lock:
ffff8880385a0998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
ffff8880385a0998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4809 [inline]
ffff8880385a0998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: sch_direct_xmit+0x15f/0x4c0 net/sched/sch_generic.c:370

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

16 locks held by kworker/u8:7/1006:
 #0: ffff88803b900938 ((wq_completion)bond1#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88803b900938 ((wq_completion)bond1#2){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc900052dfc40 ((work_completion)(&(&bond->alb_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc900052dfc40 ((work_completion)(&(&bond->alb_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #2: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #2: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: bond_alb_monitor+0xf3/0x1810 drivers/net/bonding/bond_alb.c:1546
 #3: ffffffff8e059220 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
 #4: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
 #5: ffffffff8e1c3060 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
 #5: ffffffff8e1c3060 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:893 [inline]
 #5: ffffffff8e1c3060 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x291/0x3890 net/core/dev.c:4793
 #6: ffff888035f00328 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: qdisc_run_begin include/net/sch_generic.h:205 [inline]
 #6: ffff888035f00328 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: __dev_xmit_skb net/core/dev.c:4198 [inline]
 #6: ffff888035f00328 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: __dev_queue_xmit+0x113c/0x3890 net/core/dev.c:4833
 #7: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #7: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #7: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: __rt_spin_trylock kernel/locking/spinlock_rt.c:127 [inline]
 #7: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x10c/0x2b0 kernel/locking/spinlock_rt.c:135
 #8: ffff8880385a0998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #8: ffff8880385a0998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4809 [inline]
 #8: ffff8880385a0998 (&qdisc_xmit_lock_key#4){+...}-{3:3}, at: sch_direct_xmit+0x15f/0x4c0 net/sched/sch_generic.c:370
 #9: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #9: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #9: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
 #9: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
 #10: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #10: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #10: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: ip_output+0x5a/0x450 net/ipv4/ip_output.c:432
 #11: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #11: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #11: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x3de/0x1100 net/ipv4/ip_output.c:229
 #12: ffffffff8e059220 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
 #13: ffffffff8e1c3060 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
 #13: ffffffff8e1c3060 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:893 [inline]
 #13: ffffffff8e1c3060 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x291/0x3890 net/core/dev.c:4793
 #14: ffff888038002328 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: qdisc_run_begin include/net/sch_generic.h:205 [inline]
 #14: ffff888038002328 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: __dev_xmit_skb net/core/dev.c:4198 [inline]
 #14: ffff888038002328 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: __dev_queue_xmit+0x113c/0x3890 net/core/dev.c:4833
 #15: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #15: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #15: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: __rt_spin_trylock kernel/locking/spinlock_rt.c:127 [inline]
 #15: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x10c/0x2b0 kernel/locking/spinlock_rt.c:135

stack backtrace:
CPU: 0 UID: 0 PID: 1006 Comm: kworker/u8:7 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: bond1 bond_alb_monitor
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041
 check_deadlock kernel/locking/lockdep.c:3093 [inline]
 validate_chain kernel/locking/lockdep.c:3895 [inline]
 __lock_acquire+0x24df/0x2ce0 kernel/locking/lockdep.c:5237
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56
 spin_lock include/linux/spinlock_rt.h:45 [inline]
 __netif_tx_lock include/linux/netdevice.h:4809 [inline]
 sch_direct_xmit+0x15f/0x4c0 net/sched/sch_generic.c:370
 __dev_xmit_skb net/core/dev.c:4211 [inline]
 __dev_queue_xmit+0x1acf/0x3890 net/core/dev.c:4833
 neigh_output include/net/neighbour.h:560 [inline]
 ip_finish_output2+0xc98/0x1100 net/ipv4/ip_output.c:236
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0x29f/0x450 net/ipv4/ip_output.c:437
 iptunnel_xmit+0x61b/0xd70 net/ipv4/ip_tunnel_core.c:97
 ip_tunnel_xmit+0x195e/0x2040 net/ipv4/ip_tunnel.c:848
 __gre_xmit+0x19e/0x240 net/ipv4/ip_gre.c:491
 erspan_xmit+0xad5/0x1590 net/ipv4/ip_gre.c:750
 __netdev_start_xmit include/linux/netdevice.h:5400 [inline]
 netdev_start_xmit include/linux/netdevice.h:5409 [inline]
 xmit_one net/core/dev.c:3889 [inline]
 dev_hard_start_xmit+0x2df/0x870 net/core/dev.c:3905
 sch_direct_xmit+0x257/0x4c0 net/sched/sch_generic.c:372
 __dev_xmit_skb net/core/dev.c:4211 [inline]
 __dev_queue_xmit+0x1acf/0x3890 net/core/dev.c:4833
 dev_queue_xmit include/linux/netdevice.h:3446 [inline]
 alb_send_lp_vid+0x348/0x550 drivers/net/bonding/bond_alb.c:949
 alb_send_learning_packets+0x12c/0x300 drivers/net/bonding/bond_alb.c:1012
 bond_alb_monitor+0x3d0/0x1810 drivers/net/bonding/bond_alb.c:1563
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>