============================================ WARNING: possible recursive locking detected 6.13.0-rc7-syzkaller-g1950a0af2d55 #0 Not tainted -------------------------------------------- kworker/1:5/6795 is trying to acquire lock: ffff0000d69baf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff0000d69baf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x164/0x204 net/hsr/hsr_device.c:234 but task is already holding lock: ffff0000ef148f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff0000ef148f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x164/0x204 net/hsr/hsr_device.c:234 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&hsr->seqnr_lock); lock(&hsr->seqnr_lock); *** DEADLOCK *** May be due to missing lock nesting notation 11 locks held by kworker/1:5/6795: #0: ffff0000d2332948 ((wq_completion)mld){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210 #1: ffff8000a3527c20 ((work_completion)(&(&idev->mc_ifc_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210 #2: ffff0000ee959538 (&idev->mc_lock){+.+.}-{4:4}, at: mld_ifc_work+0x3c/0xd0c net/ipv6/mcast.c:2650 #3: ffff80008fbf3160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:336 #4: ffff80008fbf3160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:336 #5: ffff80008fbf31c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:336 #6: ffff0000ef148f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #6: ffff0000ef148f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x164/0x204 net/hsr/hsr_device.c:234 #7: ffff80008fbf3160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:336 #8: ffff80008fbf31c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:336 #9: ffff80008fbf3160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:336 #10: ffff80008fbf31c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:336 stack backtrace: CPU: 1 UID: 0 PID: 6795 Comm: kworker/1:5 Not tainted 6.13.0-rc7-syzkaller-g1950a0af2d55 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: mld mld_ifc_work Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_deadlock_bug+0x4e8/0x668 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain kernel/locking/lockdep.c:3891 [inline] __lock_acquire+0x6240/0x7904 kernel/locking/lockdep.c:5226 lock_acquire+0x23c/0x724 kernel/locking/lockdep.c:5849 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x48/0x60 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] hsr_dev_xmit+0x164/0x204 net/hsr/hsr_device.c:234 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3620 [inline] dev_hard_start_xmit+0x274/0x904 net/core/dev.c:3636 __dev_queue_xmit+0x1680/0x35b4 net/core/dev.c:4466 dev_queue_xmit include/linux/netdevice.h:3168 [inline] br_dev_queue_push_xmit+0x5a4/0x758 net/bridge/br_forward.c:53 NF_HOOK+0x35c/0x408 include/linux/netfilter.h:314 br_forward_finish+0xd4/0x11c net/bridge/br_forward.c:66 NF_HOOK+0x35c/0x408 include/linux/netfilter.h:314 __br_forward+0x2f0/0x45c net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xc8/0x178 net/bridge/br_forward.c:190 br_flood+0x28c/0x5c4 net/bridge/br_forward.c:236 br_dev_xmit+0xe38/0x1670 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3620 [inline] dev_hard_start_xmit+0x274/0x904 net/core/dev.c:3636 __dev_queue_xmit+0x1680/0x35b4 net/core/dev.c:4466 dev_queue_xmit include/linux/netdevice.h:3168 [inline] hsr_xmit net/hsr/hsr_forward.c:430 [inline] hsr_forward_do net/hsr/hsr_forward.c:571 [inline] hsr_forward_skb+0x1224/0x2264 net/hsr/hsr_forward.c:730 hsr_dev_xmit+0x170/0x204 net/hsr/hsr_device.c:235 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3620 [inline] dev_hard_start_xmit+0x274/0x904 net/core/dev.c:3636 __dev_queue_xmit+0x1680/0x35b4 net/core/dev.c:4466 dev_queue_xmit include/linux/netdevice.h:3168 [inline] neigh_connected_output+0x344/0x3d8 net/core/neighbour.c:1543 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x16bc/0x214c net/ipv6/ip6_output.c:141 ip6_finish_output+0x428/0x7c4 net/ipv6/ip6_output.c:226 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0x274/0x598 net/ipv6/ip6_output.c:247 dst_output include/net/dst.h:450 [inline] NF_HOOK+0x160/0x4f0 include/linux/netfilter.h:314 mld_sendpack+0x7b8/0x10f8 net/ipv6/mcast.c:1819 mld_send_cr net/ipv6/mcast.c:2120 [inline] mld_ifc_work+0x840/0xd0c net/ipv6/mcast.c:2651 process_one_work+0x7a8/0x15cc kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x97c/0xeec kernel/workqueue.c:3398 kthread+0x288/0x310 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862