path: root/drivers/net/bonding/bond_3ad.c
diff options
authorVeaceslav Falico <vfalico@redhat.com>2014-01-10 11:59:44 +0100
committerDavid S. Miller <davem@davemloft.net>2014-01-13 22:22:27 -0800
commit768b954922e69a92a363bd4041cb93040ae4e9cf (patch)
treea6de632160b5525aaebc9e462a7790c1b41d932f /drivers/net/bonding/bond_3ad.c
parentc1bc9644ecd1f663f918d42b33b41a508683b0ee (diff)
bonding: fix __get_first_agg RCU usage
Currently, the RCU read lock usage is just wrong - it gets the slave struct under RCU and continues to use it when RCU lock is released. However, it's still safe to do this cause we didn't need the rcu_read_lock() initially - all of the __get_first_agg() callers are either holding RCU read lock or the RTNL lock, so that we can't sync while in it. Fixes: be79bd048 ("bonding: add RCU for bond_3ad_state_machine_handler()") CC: dingtianhong@huawei.com CC: Jay Vosburgh <fubar@us.ibm.com> CC: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/bonding/bond_3ad.c')
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index da0d7c54d352..b49f421346a7 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -143,11 +143,13 @@ static inline struct bonding *__get_bond_by_port(struct port *port)
* Return the aggregator of the first slave in @bond, or %NULL if it can't be
* found.
+ * The caller must hold RCU or RTNL lock.
static inline struct aggregator *__get_first_agg(struct port *port)
struct bonding *bond = __get_bond_by_port(port);
struct slave *first_slave;
+ struct aggregator *agg;
/* If there's no bond for this port, or bond has no slaves */
if (bond == NULL)
@@ -155,9 +157,10 @@ static inline struct aggregator *__get_first_agg(struct port *port)
first_slave = bond_first_slave_rcu(bond);
+ agg = first_slave ? &(SLAVE_AD_INFO(first_slave).aggregator) : NULL;
- return first_slave ? &(SLAVE_AD_INFO(first_slave).aggregator) : NULL;
+ return agg;