From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joe Lawrence , Jay Vosburgh , Andy Gospodarek , Veaceslav Falico , "David S. Miller" Subject: [PATCH 3.12 04/83] bonding: RCUify bond_set_rx_mode() Date: Fri, 6 Dec 2013 13:50:54 -0800 Message-Id: <20131206214640.475530836@linuxfoundation.org> In-Reply-To: <20131206214640.002320724@linuxfoundation.org> References: <20131206214640.002320724@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Veaceslav Falico [ Upstream commit b32418705107265dfca5edfe2b547643e53a732e ] Currently we rely on rtnl locking in bond_set_rx_mode(), however it's not always the case: RTNL: assertion failed at drivers/net/bonding/bond_main.c (3391) ... [] dump_stack+0x54/0x74 [] bond_set_rx_mode+0xc7/0xd0 [bonding] [] __dev_set_rx_mode+0x57/0xa0 [] __dev_mc_add+0x58/0x70 [] dev_mc_add+0x10/0x20 [] igmp6_group_added+0x18e/0x1d0 [] ? kmem_cache_alloc_trace+0x236/0x260 [] ipv6_dev_mc_inc+0x29f/0x320 [] ipv6_sock_mc_join+0x157/0x260 ... Fix this by using RCU primitives. Reported-by: Joe Lawrence Tested-by: Joe Lawrence CC: Jay Vosburgh CC: Andy Gospodarek Signed-off-by: Veaceslav Falico Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/bonding/bond_main.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -3395,20 +3395,20 @@ static void bond_set_rx_mode(struct net_ struct bonding *bond = netdev_priv(bond_dev); struct slave *slave; - ASSERT_RTNL(); - + rcu_read_lock(); if (USES_PRIMARY(bond->params.mode)) { - slave = rtnl_dereference(bond->curr_active_slave); + slave = rcu_dereference(bond->curr_active_slave); if (slave) { dev_uc_sync(slave->dev, bond_dev); dev_mc_sync(slave->dev, bond_dev); } } else { - bond_for_each_slave(bond, slave) { + bond_for_each_slave_rcu(bond, slave) { dev_uc_sync_multiple(slave->dev, bond_dev); dev_mc_sync_multiple(slave->dev, bond_dev); } } + rcu_read_unlock(); } static int bond_neigh_init(struct neighbour *n)