====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc2-syzkaller-00164-g95b6759a8183 #0 Not tainted ------------------------------------------------------ kworker/u8:3/49 is trying to acquire lock: ffff88807d15cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88807d15cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 but task is already holding lock: ffff888032d00958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff888032d00958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4651 [inline] ffff888032d00958 (&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:5871 __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:4651 [inline] sch_direct_xmit+0x153/0x4b0 net/sched/sch_generic.c:342 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679 dev_queue_xmit include/linux/netdevice.h:3355 [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:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4713 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x11fe/0x16a0 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226 NF_HOOK+0x9e/0x380 include/linux/netfilter.h:317 mld_sendpack+0x800/0xd80 net/ipv6/mcast.c:1868 mld_send_cr net/ipv6/mcast.c:2169 [inline] mld_ifc_work+0x835/0xde0 net/ipv6/mcast.c:2702 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 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:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __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:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4713 NF_HOOK+0x30d/0x3a0 include/linux/netfilter.h:317 arp_xmit+0x16c/0x270 net/ipv4/arp.c:664 arp_solicit+0xc1d/0xe60 net/ipv4/arp.c:392 neigh_probe net/core/neighbour.c:1024 [inline] __neigh_event_send+0xf6d/0x1560 net/core/neighbour.c:1191 neigh_event_send_probe include/net/neighbour.h:463 [inline] neigh_event_send include/net/neighbour.h:469 [inline] neigh_resolve_output+0x198/0x750 net/core/neighbour.c:1496 neigh_output include/net/neighbour.h:539 [inline] ip_finish_output2+0xd3d/0x1160 net/ipv4/ip_output.c:235 iptunnel_xmit+0x571/0xa00 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x1c3c/0x2380 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:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 sch_direct_xmit+0x241/0x4b0 net/sched/sch_generic.c:344 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679 dev_queue_xmit include/linux/netdevice.h:3355 [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:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 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 *** 9 locks held by kworker/u8:3/49: #0: ffff888057896148 ((wq_completion)bond3#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888057896148 ((wq_completion)bond3#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90000b97bc0 ((work_completion)(&(&bond->alb_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000b97bc0 ((work_completion)(&(&bond->alb_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: bond_alb_monitor+0xf1/0x1800 drivers/net/bonding/bond_alb.c:1546 #3: ffffffff8e13ee00 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #3: ffffffff8e13ee00 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #3: ffffffff8e13ee00 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4638 #4: ffff888020ef0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{3:3}, at: spin_trylock include/linux/spinlock.h:361 [inline] #4: ffff888020ef0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{3:3}, at: qdisc_run_begin include/net/sch_generic.h:197 [inline] #4: ffff888020ef0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{3:3}, at: __dev_xmit_skb net/core/dev.c:4089 [inline] #4: ffff888020ef0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{3:3}, at: __dev_queue_xmit+0x1300/0x3a70 net/core/dev.c:4679 #5: ffff888032d00958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #5: ffff888032d00958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4651 [inline] #5: ffff888032d00958 (&qdisc_xmit_lock_key#4){+.-.}-{3:3}, at: sch_direct_xmit+0x153/0x4b0 net/sched/sch_generic.c:342 #6: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #6: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #6: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x452/0x1160 net/ipv4/ip_output.c:228 #7: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #7: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #7: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: arp_xmit+0x23/0x270 net/ipv4/arp.c:662 #8: ffffffff8e13ee00 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #8: ffffffff8e13ee00 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #8: ffffffff8e13ee00 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4638 stack backtrace: CPU: 1 UID: 0 PID: 49 Comm: kworker/u8:3 Not tainted 6.16.0-rc2-syzkaller-00164-g95b6759a8183 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bond3 bond_alb_monitor Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __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:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4713 NF_HOOK+0x30d/0x3a0 include/linux/netfilter.h:317 arp_xmit+0x16c/0x270 net/ipv4/arp.c:664 arp_solicit+0xc1d/0xe60 net/ipv4/arp.c:392 neigh_probe net/core/neighbour.c:1024 [inline] __neigh_event_send+0xf6d/0x1560 net/core/neighbour.c:1191 neigh_event_send_probe include/net/neighbour.h:463 [inline] neigh_event_send include/net/neighbour.h:469 [inline] neigh_resolve_output+0x198/0x750 net/core/neighbour.c:1496 neigh_output include/net/neighbour.h:539 [inline] ip_finish_output2+0xd3d/0x1160 net/ipv4/ip_output.c:235 iptunnel_xmit+0x571/0xa00 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x1c3c/0x2380 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:5215 [inline] netdev_start_xmit include/linux/netdevice.h:5224 [inline] xmit_one net/core/dev.c:3830 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3846 sch_direct_xmit+0x241/0x4b0 net/sched/sch_generic.c:344 __dev_xmit_skb net/core/dev.c:4102 [inline] __dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679 dev_queue_xmit include/linux/netdevice.h:3355 [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:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245