From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] bonding: fix send_peer_notif leekage on rtnl
 lock congestion
Date: Mon, 05 Aug 2013 16:12:12 -0700 (PDT)
Message-ID: <20130805.161212.421332729798966037.davem@davemloft.net>
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From: Veaceslav Falico <vfalico@redhat.com>
Date: Mon,  5 Aug 2013 21:47:33 +0200

> @@ -2999,7 +3002,10 @@ void bond_activebackup_arp_mon(struct work_struct *work)
>  		if (!rtnl_trylock()) {
>  			read_lock(&bond->lock);
>  			delta_in_ticks = 1;
> -			should_notify_peers = false;
> +			if (should_notify_peers) {
> +				bond->send_peer_notif++;

I doubt this increment to a shared datastructure is safe with
the locks you hold here.

You don't hold RTNL and you only have bond->lock as a reader.