====================================================== WARNING: possible circular locking dependency detected 6.16.0-syzkaller-12084-g33caa208dba6 #0 Not tainted ------------------------------------------------------ kworker/u8:9/6900 is trying to acquire lock: ffff88807ea28f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88807ea28f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 but task is already holding lock: ffff88805ab74958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88805ab74958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4656 [inline] ffff88805ab74958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: sch_direct_xmit+0x153/0x4b0 net/sched/sch_generic.c:342 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] __netif_tx_lock include/linux/netdevice.h:4656 [inline] sch_direct_xmit+0x153/0x4b0 net/sched/sch_generic.c:342 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x1857/0x3b50 net/core/dev.c:4679 dev_queue_xmit include/linux/netdevice.h:3358 [inline] hsr_xmit net/hsr/hsr_forward.c:430 [inline] hsr_forward_do net/hsr/hsr_forward.c:571 [inline] hsr_forward_skb+0x158b/0x2860 net/hsr/hsr_forward.c:733 hsr_dev_xmit+0x1a5/0x220 net/hsr/hsr_device.c:235 __netdev_start_xmit include/linux/netdevice.h:5219 [inline] netdev_start_xmit include/linux/netdevice.h:5228 [inline] xmit_one net/core/dev.c:3827 [inline] dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3843 __dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4713 neigh_output include/net/neighbour.h:547 [inline] ip6_finish_output2+0x11fe/0x16a0 net/ipv6/ip6_output.c:141 NF_HOOK include/linux/netfilter.h:318 [inline] ndisc_send_skb+0xb54/0x1440 net/ipv6/ndisc.c:512 ndisc_send_ns+0xcb/0x150 net/ipv6/ndisc.c:670 addrconf_dad_work+0xaae/0x14b0 net/ipv6/addrconf.c:4282 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (&hsr->seqnr_lock){+.-.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 __netdev_start_xmit include/linux/netdevice.h:5219 [inline] netdev_start_xmit include/linux/netdevice.h:5228 [inline] xmit_one net/core/dev.c:3827 [inline] dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3843 __dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4713 NF_HOOK+0x310/0x3a0 include/linux/netfilter.h:-1 arp_xmit+0x16c/0x270 net/ipv4/arp.c:664 arp_solicit+0xc1d/0xe60 net/ipv4/arp.c:392 neigh_probe net/core/neighbour.c:1098 [inline] __neigh_event_send+0xf70/0x1560 net/core/neighbour.c:1271 neigh_event_send_probe include/net/neighbour.h:471 [inline] neigh_event_send include/net/neighbour.h:477 [inline] neigh_resolve_output+0x198/0x750 net/core/neighbour.c:1579 neigh_output include/net/neighbour.h:547 [inline] ip_finish_output2+0xd40/0x1160 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip_output+0x2a1/0x3c0 net/ipv4/ip_output.c:436 iptunnel_xmit+0x592/0xa40 net/ipv4/ip_tunnel_core.c:84 ip_tunnel_xmit+0x1c41/0x2390 net/ipv4/ip_tunnel.c:859 __gre_xmit net/ipv4/ip_gre.c:488 [inline] gre_tap_xmit+0x590/0x7a0 net/ipv4/ip_gre.c:776 __netdev_start_xmit include/linux/netdevice.h:5219 [inline] netdev_start_xmit include/linux/netdevice.h:5228 [inline] xmit_one net/core/dev.c:3827 [inline] dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3843 sch_direct_xmit+0x241/0x4b0 net/sched/sch_generic.c:344 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x1857/0x3b50 net/core/dev.c:4679 dev_queue_xmit include/linux/netdevice.h:3358 [inline] alb_send_lp_vid+0x324/0x510 drivers/net/bonding/bond_alb.c:949 alb_send_learning_packets+0x10d/0x2c0 drivers/net/bonding/bond_alb.c:1012 bond_alb_monitor+0x3e4/0x1800 drivers/net/bonding/bond_alb.c:1563 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&qdisc_xmit_lock_key#4); lock(&hsr->seqnr_lock); lock(&qdisc_xmit_lock_key#4); lock(&hsr->seqnr_lock); *** DEADLOCK *** 10 locks held by kworker/u8:9/6900: #0: ffff888056f02948 ((wq_completion)bond6#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888056f02948 ((wq_completion)bond6#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9001a5bfbc0 ((work_completion)(&(&bond->alb_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9001a5bfbc0 ((work_completion)(&(&bond->alb_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: bond_alb_monitor+0xf1/0x1800 drivers/net/bonding/bond_alb.c:1546 #3: ffffffff8e139f40 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #3: ffffffff8e139f40 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #3: ffffffff8e139f40 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50 net/core/dev.c:4638 #4: ffff888026678258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#3){+...}-{3:3}, at: spin_trylock include/linux/spinlock.h:361 [inline] #4: ffff888026678258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#3){+...}-{3:3}, at: qdisc_run_begin include/net/sch_generic.h:197 [inline] #4: ffff888026678258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#3){+...}-{3:3}, at: __dev_xmit_skb net/core/dev.c:4089 [inline] #4: ffff888026678258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#3){+...}-{3:3}, at: __dev_queue_xmit+0x138a/0x3b50 net/core/dev.c:4679 #5: ffff88805ab74958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #5: ffff88805ab74958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4656 [inline] #5: ffff88805ab74958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: sch_direct_xmit+0x153/0x4b0 net/sched/sch_generic.c:342 #6: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #6: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #6: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: ip_output+0x60/0x3c0 net/ipv4/ip_output.c:431 #7: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #7: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #7: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x452/0x1160 net/ipv4/ip_output.c:228 #8: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #8: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #8: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: arp_xmit+0x23/0x270 net/ipv4/arp.c:662 #9: ffffffff8e139f40 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #9: ffffffff8e139f40 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #9: ffffffff8e139f40 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50 net/core/dev.c:4638 stack backtrace: CPU: 0 UID: 0 PID: 6900 Comm: kworker/u8:9 Not tainted 6.16.0-syzkaller-12084-g33caa208dba6 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bond6 bond_alb_monitor Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 __netdev_start_xmit include/linux/netdevice.h:5219 [inline] netdev_start_xmit include/linux/netdevice.h:5228 [inline] xmit_one net/core/dev.c:3827 [inline] dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3843 __dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4713 NF_HOOK+0x310/0x3a0 include/linux/netfilter.h:-1 arp_xmit+0x16c/0x270 net/ipv4/arp.c:664 arp_solicit+0xc1d/0xe60 net/ipv4/arp.c:392 neigh_probe net/core/neighbour.c:1098 [inline] __neigh_event_send+0xf70/0x1560 net/core/neighbour.c:1271 neigh_event_send_probe include/net/neighbour.h:471 [inline] neigh_event_send include/net/neighbour.h:477 [inline] neigh_resolve_output+0x198/0x750 net/core/neighbour.c:1579 neigh_output include/net/neighbour.h:547 [inline] ip_finish_output2+0xd40/0x1160 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip_output+0x2a1/0x3c0 net/ipv4/ip_output.c:436 iptunnel_xmit+0x592/0xa40 net/ipv4/ip_tunnel_core.c:84 ip_tunnel_xmit+0x1c41/0x2390 net/ipv4/ip_tunnel.c:859 __gre_xmit net/ipv4/ip_gre.c:488 [inline] gre_tap_xmit+0x590/0x7a0 net/ipv4/ip_gre.c:776 __netdev_start_xmit include/linux/netdevice.h:5219 [inline] netdev_start_xmit include/linux/netdevice.h:5228 [inline] xmit_one net/core/dev.c:3827 [inline] dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3843 sch_direct_xmit+0x241/0x4b0 net/sched/sch_generic.c:344 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x1857/0x3b50 net/core/dev.c:4679 dev_queue_xmit include/linux/netdevice.h:3358 [inline] alb_send_lp_vid+0x324/0x510 drivers/net/bonding/bond_alb.c:949 alb_send_learning_packets+0x10d/0x2c0 drivers/net/bonding/bond_alb.c:1012 bond_alb_monitor+0x3e4/0x1800 drivers/net/bonding/bond_alb.c:1563 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 netdevsim netdevsim3 netdevsim0: unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim0: unset [1, 1] type 2 family 0 port 19999 - 0 netdevsim netdevsim3 netdevsim1: unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim1: unset [1, 1] type 2 family 0 port 19999 - 0 netdevsim netdevsim3 netdevsim2: unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim2: unset [1, 1] type 2 family 0 port 19999 - 0 netdevsim netdevsim3 netdevsim3: unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim3: unset [1, 1] type 2 family 0 port 19999 - 0