| Message ID | 1389266425-28365-4-git-send-email-vfalico@redhat.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
On 2014/1/9 19:20, Veaceslav Falico wrote: > Currently, the implementation is meaningless - once again, we take the > slave structure and use it after we've exited RCU critical section. > > Fix this by removing the rcu_read_lock() from __get_active_agg(), and > ensuring that all its callers are holding either RCU or RTNL lock. > > 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> > --- > > Notes: > v1 -> v2: > Don't use RCU primitives as we can hold RTNL. > > drivers/net/bonding/bond_3ad.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c > index d2782c8..845545b 100644 > --- a/drivers/net/bonding/bond_3ad.c > +++ b/drivers/net/bonding/bond_3ad.c > @@ -674,6 +674,8 @@ static u32 __get_agg_bandwidth(struct aggregator *aggregator) > /** > * __get_active_agg - get the current active aggregator > * @aggregator: the aggregator we're looking at > + * > + * Caller must hold either RCU or RTNL lock. > */ > static struct aggregator *__get_active_agg(struct aggregator *aggregator) > { > @@ -681,13 +683,9 @@ static struct aggregator *__get_active_agg(struct aggregator *aggregator) > struct list_head *iter; > struct slave *slave; > > - rcu_read_lock(); > - bond_for_each_slave_rcu(bond, slave, iter) > - if (SLAVE_AD_INFO(slave).aggregator.is_active) { > - rcu_read_unlock(); > + bond_for_each_slave(bond, slave, iter) > + if (SLAVE_AD_INFO(slave).aggregator.is_active) > return &(SLAVE_AD_INFO(slave).aggregator); > - } Is the bond_for_each_slave safe in rcu_read_lock()? > - rcu_read_unlock(); > > return NULL; > } > @@ -1495,11 +1493,11 @@ static void ad_agg_selection_logic(struct aggregator *agg) > struct slave *slave; > struct port *port; > > + rcu_read_lock(); > origin = agg; > active = __get_active_agg(agg); > best = (active && agg_device_up(active)) ? active : NULL; > > - rcu_read_lock(); > bond_for_each_slave_rcu(bond, slave, iter) { > agg = &(SLAVE_AD_INFO(slave).aggregator); > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 09, 2014 at 08:04:25PM +0800, Ding Tianhong wrote: >On 2014/1/9 19:20, Veaceslav Falico wrote: >> Currently, the implementation is meaningless - once again, we take the >> slave structure and use it after we've exited RCU critical section. >> >> Fix this by removing the rcu_read_lock() from __get_active_agg(), and >> ensuring that all its callers are holding either RCU or RTNL lock. >> >> 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> >> --- >> >> Notes: >> v1 -> v2: >> Don't use RCU primitives as we can hold RTNL. >> >> drivers/net/bonding/bond_3ad.c | 12 +++++------- >> 1 file changed, 5 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c >> index d2782c8..845545b 100644 >> --- a/drivers/net/bonding/bond_3ad.c >> +++ b/drivers/net/bonding/bond_3ad.c >> @@ -674,6 +674,8 @@ static u32 __get_agg_bandwidth(struct aggregator *aggregator) >> /** >> * __get_active_agg - get the current active aggregator >> * @aggregator: the aggregator we're looking at >> + * >> + * Caller must hold either RCU or RTNL lock. >> */ >> static struct aggregator *__get_active_agg(struct aggregator *aggregator) >> { >> @@ -681,13 +683,9 @@ static struct aggregator *__get_active_agg(struct aggregator *aggregator) >> struct list_head *iter; >> struct slave *slave; >> >> - rcu_read_lock(); >> - bond_for_each_slave_rcu(bond, slave, iter) >> - if (SLAVE_AD_INFO(slave).aggregator.is_active) { >> - rcu_read_unlock(); >> + bond_for_each_slave(bond, slave, iter) >> + if (SLAVE_AD_INFO(slave).aggregator.is_active) >> return &(SLAVE_AD_INFO(slave).aggregator); >> - } > >Is the bond_for_each_slave safe in rcu_read_lock()? Yeah, good catch, responded in the second patch. Thanks for the review! > > >> - rcu_read_unlock(); >> >> return NULL; >> } >> @@ -1495,11 +1493,11 @@ static void ad_agg_selection_logic(struct aggregator *agg) >> struct slave *slave; >> struct port *port; >> >> + rcu_read_lock(); >> origin = agg; >> active = __get_active_agg(agg); >> best = (active && agg_device_up(active)) ? active : NULL; >> >> - rcu_read_lock(); >> bond_for_each_slave_rcu(bond, slave, iter) { >> agg = &(SLAVE_AD_INFO(slave).aggregator); >> >> > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index d2782c8..845545b 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -674,6 +674,8 @@ static u32 __get_agg_bandwidth(struct aggregator *aggregator) /** * __get_active_agg - get the current active aggregator * @aggregator: the aggregator we're looking at + * + * Caller must hold either RCU or RTNL lock. */ static struct aggregator *__get_active_agg(struct aggregator *aggregator) { @@ -681,13 +683,9 @@ static struct aggregator *__get_active_agg(struct aggregator *aggregator) struct list_head *iter; struct slave *slave; - rcu_read_lock(); - bond_for_each_slave_rcu(bond, slave, iter) - if (SLAVE_AD_INFO(slave).aggregator.is_active) { - rcu_read_unlock(); + bond_for_each_slave(bond, slave, iter) + if (SLAVE_AD_INFO(slave).aggregator.is_active) return &(SLAVE_AD_INFO(slave).aggregator); - } - rcu_read_unlock(); return NULL; } @@ -1495,11 +1493,11 @@ static void ad_agg_selection_logic(struct aggregator *agg) struct slave *slave; struct port *port; + rcu_read_lock(); origin = agg; active = __get_active_agg(agg); best = (active && agg_device_up(active)) ? active : NULL; - rcu_read_lock(); bond_for_each_slave_rcu(bond, slave, iter) { agg = &(SLAVE_AD_INFO(slave).aggregator);
Currently, the implementation is meaningless - once again, we take the slave structure and use it after we've exited RCU critical section. Fix this by removing the rcu_read_lock() from __get_active_agg(), and ensuring that all its callers are holding either RCU or RTNL lock. 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> --- Notes: v1 -> v2: Don't use RCU primitives as we can hold RTNL. drivers/net/bonding/bond_3ad.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)