Re: [PATCH v4 net-next 01/12] bonding: remove bond->lock from bond_arp_rcv
From: Ding Tianhong <hidden>
Date: 2014-02-18 04:03:14
On 2014/2/17 22:41, Veaceslav Falico wrote:
quoted hunk ↗ jump to hunk
We're always called with rcu_read_lock() held (bond_arp_rcv() is only called from bond_handle_frame(), which is rx_handler and always called under rcu from __netif_receive_skb_core() ). The slave active/passive and/or bonding params can change in-flight, however we don't really care about that - we only modify the last time packet was received, which is harmless. CC: Jay Vosburgh <redacted> CC: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: Veaceslav Falico <redacted> --- drivers/net/bonding/bond_main.c | 3 --- 1 file changed, 3 deletions(-)diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 3bce855..3c50bec 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c@@ -2260,8 +2260,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond, if (skb->protocol != __cpu_to_be16(ETH_P_ARP)) return RX_HANDLER_ANOTHER; - read_lock(&bond->lock); - if (!slave_do_arp_validate(bond, slave)) goto out_unlock;@@ -2318,7 +2316,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond, bond_validate_arp(bond, slave, tip, sip); out_unlock: - read_unlock(&bond->lock); if (arp != (struct arphdr *)skb->data) kfree(arp); return RX_HANDLER_ANOTHER;
I think it is not enough, you should add rcu_dereference for bond->curr_active_slave, it may be changed during the recv processing. Regards Ding