* [PATCH 1/5] bridge: add RCU annotation to bridge multicast table
2010-11-14 21:12 [PATCH 0/5] bridge: RCU annotation and cleanup Stephen Hemminger
@ 2010-11-14 21:12 ` Stephen Hemminger
2010-11-14 21:12 ` [PATCH 2/5] bridge: add proper RCU annotation to should_route_hook Stephen Hemminger
` (4 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Stephen Hemminger @ 2010-11-14 21:12 UTC (permalink / raw)
To: David Miller, Eric Dumazet; +Cc: netdev, bridge
[-- Attachment #1: bridge-mlock-rcu.patch --]
[-- Type: text/plain, Size: 10144 bytes --]
From: Eric Dumazet <eric.dumazet@gmail.com>
Add modern __rcu annotatations to bridge multicast table.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
---
net/bridge/br_forward.c | 4 +-
net/bridge/br_multicast.c | 78 ++++++++++++++++++++++++++++++----------------
net/bridge/br_private.h | 6 +--
3 files changed, 56 insertions(+), 32 deletions(-)
--- a/net/bridge/br_multicast.c 2010-11-14 12:36:30.383348571 -0800
+++ b/net/bridge/br_multicast.c 2010-11-14 12:36:37.084167303 -0800
@@ -33,6 +33,9 @@
#include "br_private.h"
+#define mlock_dereference(X, br) \
+ rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))
+
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
static inline int ipv6_is_local_multicast(const struct in6_addr *addr)
{
@@ -135,7 +138,7 @@ static struct net_bridge_mdb_entry *br_m
struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
struct sk_buff *skb)
{
- struct net_bridge_mdb_htable *mdb = br->mdb;
+ struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
struct br_ip ip;
if (br->multicast_disabled)
@@ -235,7 +238,8 @@ static void br_multicast_group_expired(u
if (mp->ports)
goto out;
- mdb = br->mdb;
+ mdb = mlock_dereference(br->mdb, br);
+
hlist_del_rcu(&mp->hlist[mdb->ver]);
mdb->size--;
@@ -249,16 +253,20 @@ out:
static void br_multicast_del_pg(struct net_bridge *br,
struct net_bridge_port_group *pg)
{
- struct net_bridge_mdb_htable *mdb = br->mdb;
+ struct net_bridge_mdb_htable *mdb;
struct net_bridge_mdb_entry *mp;
struct net_bridge_port_group *p;
- struct net_bridge_port_group **pp;
+ struct net_bridge_port_group __rcu **pp;
+
+ mdb = mlock_dereference(br->mdb, br);
mp = br_mdb_ip_get(mdb, &pg->addr);
if (WARN_ON(!mp))
return;
- for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+ for (pp = &mp->ports;
+ (p = mlock_dereference(*pp, br)) != NULL;
+ pp = &p->next) {
if (p != pg)
continue;
@@ -294,10 +302,10 @@ out:
spin_unlock(&br->multicast_lock);
}
-static int br_mdb_rehash(struct net_bridge_mdb_htable **mdbp, int max,
+static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
int elasticity)
{
- struct net_bridge_mdb_htable *old = *mdbp;
+ struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
struct net_bridge_mdb_htable *mdb;
int err;
@@ -569,7 +577,7 @@ static struct net_bridge_mdb_entry *br_m
struct net_bridge *br, struct net_bridge_port *port,
struct br_ip *group, int hash)
{
- struct net_bridge_mdb_htable *mdb = br->mdb;
+ struct net_bridge_mdb_htable *mdb;
struct net_bridge_mdb_entry *mp;
struct hlist_node *p;
unsigned count = 0;
@@ -577,6 +585,7 @@ static struct net_bridge_mdb_entry *br_m
int elasticity;
int err;
+ mdb = rcu_dereference_protected(br->mdb, 1);
hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
count++;
if (unlikely(br_ip_equal(group, &mp->addr)))
@@ -642,10 +651,11 @@ static struct net_bridge_mdb_entry *br_m
struct net_bridge *br, struct net_bridge_port *port,
struct br_ip *group)
{
- struct net_bridge_mdb_htable *mdb = br->mdb;
+ struct net_bridge_mdb_htable *mdb;
struct net_bridge_mdb_entry *mp;
int hash;
+ mdb = rcu_dereference_protected(br->mdb, 1);
if (!mdb) {
if (br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0))
return NULL;
@@ -660,7 +670,7 @@ static struct net_bridge_mdb_entry *br_m
case -EAGAIN:
rehash:
- mdb = br->mdb;
+ mdb = rcu_dereference_protected(br->mdb, 1);
hash = br_ip_hash(mdb, group);
break;
@@ -692,7 +702,7 @@ static int br_multicast_add_group(struct
{
struct net_bridge_mdb_entry *mp;
struct net_bridge_port_group *p;
- struct net_bridge_port_group **pp;
+ struct net_bridge_port_group __rcu **pp;
unsigned long now = jiffies;
int err;
@@ -712,7 +722,9 @@ static int br_multicast_add_group(struct
goto out;
}
- for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+ for (pp = &mp->ports;
+ (p = mlock_dereference(*pp, br)) != NULL;
+ pp = &p->next) {
if (p->port == port)
goto found;
if ((unsigned long)p->port < (unsigned long)port)
@@ -1106,7 +1118,7 @@ static int br_ip4_multicast_query(struct
struct net_bridge_mdb_entry *mp;
struct igmpv3_query *ih3;
struct net_bridge_port_group *p;
- struct net_bridge_port_group **pp;
+ struct net_bridge_port_group __rcu **pp;
unsigned long max_delay;
unsigned long now = jiffies;
__be32 group;
@@ -1145,7 +1157,7 @@ static int br_ip4_multicast_query(struct
if (!group)
goto out;
- mp = br_mdb_ip4_get(br->mdb, group);
+ mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
if (!mp)
goto out;
@@ -1157,7 +1169,9 @@ static int br_ip4_multicast_query(struct
try_to_del_timer_sync(&mp->timer) >= 0))
mod_timer(&mp->timer, now + max_delay);
- for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+ for (pp = &mp->ports;
+ (p = mlock_dereference(*pp, br)) != NULL;
+ pp = &p->next) {
if (timer_pending(&p->timer) ?
time_after(p->timer.expires, now + max_delay) :
try_to_del_timer_sync(&p->timer) >= 0)
@@ -1178,7 +1192,8 @@ static int br_ip6_multicast_query(struct
struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
struct net_bridge_mdb_entry *mp;
struct mld2_query *mld2q;
- struct net_bridge_port_group *p, **pp;
+ struct net_bridge_port_group *p;
+ struct net_bridge_port_group __rcu **pp;
unsigned long max_delay;
unsigned long now = jiffies;
struct in6_addr *group = NULL;
@@ -1214,7 +1229,7 @@ static int br_ip6_multicast_query(struct
if (!group)
goto out;
- mp = br_mdb_ip6_get(br->mdb, group);
+ mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
if (!mp)
goto out;
@@ -1225,7 +1240,9 @@ static int br_ip6_multicast_query(struct
try_to_del_timer_sync(&mp->timer) >= 0))
mod_timer(&mp->timer, now + max_delay);
- for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+ for (pp = &mp->ports;
+ (p = mlock_dereference(*pp, br)) != NULL;
+ pp = &p->next) {
if (timer_pending(&p->timer) ?
time_after(p->timer.expires, now + max_delay) :
try_to_del_timer_sync(&p->timer) >= 0)
@@ -1254,7 +1271,7 @@ static void br_multicast_leave_group(str
timer_pending(&br->multicast_querier_timer))
goto out;
- mdb = br->mdb;
+ mdb = mlock_dereference(br->mdb, br);
mp = br_mdb_ip_get(mdb, group);
if (!mp)
goto out;
@@ -1277,7 +1294,9 @@ static void br_multicast_leave_group(str
goto out;
}
- for (p = mp->ports; p; p = p->next) {
+ for (p = mlock_dereference(mp->ports, br);
+ p != NULL;
+ p = mlock_dereference(p->next, br)) {
if (p->port != port)
continue;
@@ -1625,7 +1644,7 @@ void br_multicast_stop(struct net_bridge
del_timer_sync(&br->multicast_query_timer);
spin_lock_bh(&br->multicast_lock);
- mdb = br->mdb;
+ mdb = mlock_dereference(br->mdb, br);
if (!mdb)
goto out;
@@ -1729,6 +1748,7 @@ int br_multicast_toggle(struct net_bridg
{
struct net_bridge_port *port;
int err = 0;
+ struct net_bridge_mdb_htable *mdb;
spin_lock(&br->multicast_lock);
if (br->multicast_disabled == !val)
@@ -1741,15 +1761,16 @@ int br_multicast_toggle(struct net_bridg
if (!netif_running(br->dev))
goto unlock;
- if (br->mdb) {
- if (br->mdb->old) {
+ mdb = mlock_dereference(br->mdb, br);
+ if (mdb) {
+ if (mdb->old) {
err = -EEXIST;
rollback:
br->multicast_disabled = !!val;
goto unlock;
}
- err = br_mdb_rehash(&br->mdb, br->mdb->max,
+ err = br_mdb_rehash(&br->mdb, mdb->max,
br->hash_elasticity);
if (err)
goto rollback;
@@ -1774,6 +1795,7 @@ int br_multicast_set_hash_max(struct net
{
int err = -ENOENT;
u32 old;
+ struct net_bridge_mdb_htable *mdb;
spin_lock(&br->multicast_lock);
if (!netif_running(br->dev))
@@ -1782,7 +1804,9 @@ int br_multicast_set_hash_max(struct net
err = -EINVAL;
if (!is_power_of_2(val))
goto unlock;
- if (br->mdb && val < br->mdb->size)
+
+ mdb = mlock_dereference(br->mdb, br);
+ if (mdb && val < mdb->size)
goto unlock;
err = 0;
@@ -1790,8 +1814,8 @@ int br_multicast_set_hash_max(struct net
old = br->hash_max;
br->hash_max = val;
- if (br->mdb) {
- if (br->mdb->old) {
+ if (mdb) {
+ if (mdb->old) {
err = -EEXIST;
rollback:
br->hash_max = old;
--- a/net/bridge/br_private.h 2010-11-14 12:36:30.399350527 -0800
+++ b/net/bridge/br_private.h 2010-11-14 12:44:07.257410977 -0800
@@ -72,7 +72,7 @@ struct net_bridge_fdb_entry
struct net_bridge_port_group {
struct net_bridge_port *port;
- struct net_bridge_port_group *next;
+ struct net_bridge_port_group __rcu *next;
struct hlist_node mglist;
struct rcu_head rcu;
struct timer_list timer;
@@ -86,7 +86,7 @@ struct net_bridge_mdb_entry
struct hlist_node hlist[2];
struct hlist_node mglist;
struct net_bridge *br;
- struct net_bridge_port_group *ports;
+ struct net_bridge_port_group __rcu *ports;
struct rcu_head rcu;
struct timer_list timer;
struct timer_list query_timer;
@@ -227,7 +227,7 @@ struct net_bridge
unsigned long multicast_startup_query_interval;
spinlock_t multicast_lock;
- struct net_bridge_mdb_htable *mdb;
+ struct net_bridge_mdb_htable __rcu *mdb;
struct hlist_head router_list;
struct hlist_head mglist;
--- a/net/bridge/br_forward.c 2010-11-14 12:36:47.833478598 -0800
+++ b/net/bridge/br_forward.c 2010-11-14 12:42:22.001208297 -0800
@@ -223,7 +223,7 @@ static void br_multicast_flood(struct ne
struct net_bridge_port_group *p;
struct hlist_node *rp;
- rp = rcu_dereference(br->router_list.first);
+ rp = rcu_dereference(hlist_first_rcu(&br->router_list));
p = mdst ? rcu_dereference(mdst->ports) : NULL;
while (p || rp) {
struct net_bridge_port *port, *lport, *rport;
@@ -242,7 +242,7 @@ static void br_multicast_flood(struct ne
if ((unsigned long)lport >= (unsigned long)port)
p = rcu_dereference(p->next);
if ((unsigned long)rport >= (unsigned long)port)
- rp = rcu_dereference(rp->next);
+ rp = rcu_dereference(hlist_next_rcu(rp->next));
}
if (!prev)
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH 2/5] bridge: add proper RCU annotation to should_route_hook
2010-11-14 21:12 [PATCH 0/5] bridge: RCU annotation and cleanup Stephen Hemminger
2010-11-14 21:12 ` [PATCH 1/5] bridge: add RCU annotation to bridge multicast table Stephen Hemminger
@ 2010-11-14 21:12 ` Stephen Hemminger
2010-11-14 21:12 ` [PATCH 3/5] netdev: add rcu annotations to receive handler hook Stephen Hemminger
` (3 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Stephen Hemminger @ 2010-11-14 21:12 UTC (permalink / raw)
To: David Miller, Eric Dumazet; +Cc: netdev, bridge
[-- Attachment #1: bridge-hook-typedef.patch --]
[-- Type: text/plain, Size: 3022 bytes --]
From: Eric Dumazet <eric.dumazet@gmail.com>
Add br_should_route_hook_t typedef, this is the only way we can
get a clean RCU implementation for function pointer.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
---
include/linux/if_bridge.h | 4 +++-
net/bridge/br.c | 4 ----
net/bridge/br_input.c | 10 +++++++---
net/bridge/netfilter/ebtable_broute.c | 3 ++-
4 files changed, 12 insertions(+), 9 deletions(-)
--- a/net/bridge/br.c 2010-11-14 11:18:54.048692005 -0800
+++ b/net/bridge/br.c 2010-11-14 11:19:47.347027185 -0800
@@ -22,8 +22,6 @@
#include "br_private.h"
-int (*br_should_route_hook)(struct sk_buff *skb);
-
static const struct stp_proto br_stp_proto = {
.rcv = br_stp_rcv,
};
@@ -102,8 +100,6 @@ static void __exit br_deinit(void)
br_fdb_fini();
}
-EXPORT_SYMBOL(br_should_route_hook);
-
module_init(br_init)
module_exit(br_deinit)
MODULE_LICENSE("GPL");
--- a/net/bridge/br_input.c 2010-11-14 11:18:54.048692005 -0800
+++ b/net/bridge/br_input.c 2010-11-14 11:41:40.558700481 -0800
@@ -21,6 +21,10 @@
/* Bridge group multicast address 802.1d (pg 51). */
const u8 br_group_address[ETH_ALEN] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
+/* Hook for brouter */
+br_should_route_hook_t __rcu *br_should_route_hook __read_mostly;
+EXPORT_SYMBOL(br_should_route_hook);
+
static int br_pass_frame_up(struct sk_buff *skb)
{
struct net_device *indev, *brdev = BR_INPUT_SKB_CB(skb)->brdev;
@@ -139,7 +143,7 @@ struct sk_buff *br_handle_frame(struct s
{
struct net_bridge_port *p;
const unsigned char *dest = eth_hdr(skb)->h_dest;
- int (*rhook)(struct sk_buff *skb);
+ br_should_route_hook_t *rhook;
if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
return skb;
@@ -173,8 +177,8 @@ forward:
switch (p->state) {
case BR_STATE_FORWARDING:
rhook = rcu_dereference(br_should_route_hook);
- if (rhook != NULL) {
- if (rhook(skb))
+ if (rhook) {
+ if ((*rhook)(skb))
return skb;
dest = eth_hdr(skb)->h_dest;
}
--- a/include/linux/if_bridge.h 2010-11-14 11:18:54.048692005 -0800
+++ b/include/linux/if_bridge.h 2010-11-14 11:19:47.351028008 -0800
@@ -102,7 +102,9 @@ struct __fdb_entry {
#include <linux/netdevice.h>
extern void brioctl_set(int (*ioctl_hook)(struct net *, unsigned int, void __user *));
-extern int (*br_should_route_hook)(struct sk_buff *skb);
+
+typedef int (*br_should_route_hook_t)(struct sk_buff *skb);
+extern br_should_route_hook_t __rcu *br_should_route_hook;
#endif
--- a/net/bridge/netfilter/ebtable_broute.c 2010-11-14 11:20:39.745149494 -0800
+++ b/net/bridge/netfilter/ebtable_broute.c 2010-11-14 11:21:01.020917528 -0800
@@ -87,7 +87,8 @@ static int __init ebtable_broute_init(vo
if (ret < 0)
return ret;
/* see br_input.c */
- rcu_assign_pointer(br_should_route_hook, ebt_broute);
+ rcu_assign_pointer(br_should_route_hook,
+ (br_should_route_hook_t *)ebt_broute);
return 0;
}
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH 3/5] netdev: add rcu annotations to receive handler hook
2010-11-14 21:12 [PATCH 0/5] bridge: RCU annotation and cleanup Stephen Hemminger
2010-11-14 21:12 ` [PATCH 1/5] bridge: add RCU annotation to bridge multicast table Stephen Hemminger
2010-11-14 21:12 ` [PATCH 2/5] bridge: add proper RCU annotation to should_route_hook Stephen Hemminger
@ 2010-11-14 21:12 ` Stephen Hemminger
2010-11-14 21:12 ` [PATCH 4/5] bridge: fix RCU races with bridge port Stephen Hemminger
` (2 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Stephen Hemminger @ 2010-11-14 21:12 UTC (permalink / raw)
To: David Miller, Eric Dumazet; +Cc: netdev, bridge
[-- Attachment #1: rx_handler_rcu.patch --]
[-- Type: text/plain, Size: 595 bytes --]
Suggested by Eric's bridge RCU changes.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
---
include/linux/netdevice.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/include/linux/netdevice.h 2010-11-14 11:41:53.224298362 -0800
+++ b/include/linux/netdevice.h 2010-11-14 11:42:42.546359900 -0800
@@ -995,8 +995,8 @@ struct net_device {
unsigned int real_num_rx_queues;
#endif
- rx_handler_func_t *rx_handler;
- void *rx_handler_data;
+ rx_handler_func_t __rcu *rx_handler;
+ void __rcu *rx_handler_data;
struct netdev_queue __rcu *ingress_queue;
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH 4/5] bridge: fix RCU races with bridge port
2010-11-14 21:12 [PATCH 0/5] bridge: RCU annotation and cleanup Stephen Hemminger
` (2 preceding siblings ...)
2010-11-14 21:12 ` [PATCH 3/5] netdev: add rcu annotations to receive handler hook Stephen Hemminger
@ 2010-11-14 21:12 ` Stephen Hemminger
2010-11-14 21:12 ` [PATCH 5/5] bridge: add RCU annotations to bridge port lookup Stephen Hemminger
2010-11-15 12:23 ` [PATCH 0/5] bridge: RCU annotation and cleanup Tetsuo Handa
5 siblings, 0 replies; 9+ messages in thread
From: Stephen Hemminger @ 2010-11-14 21:12 UTC (permalink / raw)
To: David Miller, Eric Dumazet; +Cc: netdev, bridge
[-- Attachment #1: br-port-rcu-race.patch --]
[-- Type: text/plain, Size: 6647 bytes --]
The macro br_port_exists() is not enough protection when only
RCU is being used. There is a tiny race where other CPU has cleared port
handler hook, but is bridge port flag might still be set.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
---
net/bridge/br_fdb.c | 15 +++++++++------
net/bridge/br_if.c | 5 +----
net/bridge/br_netfilter.c | 13 +++++++------
net/bridge/br_netlink.c | 10 ++++++----
net/bridge/br_notify.c | 2 +-
net/bridge/br_private.h | 16 +++++++++++++---
net/bridge/br_stp_bpdu.c | 8 ++++----
net/bridge/netfilter/ebtables.c | 11 +++++------
8 files changed, 46 insertions(+), 34 deletions(-)
--- a/net/bridge/br_netfilter.c 2010-11-14 12:36:22.970441653 -0800
+++ b/net/bridge/br_netfilter.c 2010-11-14 12:44:55.666987357 -0800
@@ -131,17 +131,18 @@ void br_netfilter_rtable_init(struct net
static inline struct rtable *bridge_parent_rtable(const struct net_device *dev)
{
- if (!br_port_exists(dev))
- return NULL;
- return &br_port_get_rcu(dev)->br->fake_rtable;
+ struct net_bridge_port *port;
+
+ port = br_port_get_rcu(dev);
+ return port ? &port->br->fake_rtable : NULL;
}
static inline struct net_device *bridge_parent(const struct net_device *dev)
{
- if (!br_port_exists(dev))
- return NULL;
+ struct net_bridge_port *port;
- return br_port_get_rcu(dev)->br->dev;
+ port = br_port_get_rcu(dev);
+ return port ? port->br->dev : NULL;
}
static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
--- a/net/bridge/br_stp_bpdu.c 2010-11-14 12:36:22.982443121 -0800
+++ b/net/bridge/br_stp_bpdu.c 2010-11-14 12:44:55.666987357 -0800
@@ -141,10 +141,6 @@ void br_stp_rcv(const struct stp_proto *
struct net_bridge *br;
const unsigned char *buf;
- if (!br_port_exists(dev))
- goto err;
- p = br_port_get_rcu(dev);
-
if (!pskb_may_pull(skb, 4))
goto err;
@@ -153,6 +149,10 @@ void br_stp_rcv(const struct stp_proto *
if (buf[0] != 0 || buf[1] != 0 || buf[2] != 0)
goto err;
+ p = br_port_get_rcu(dev);
+ if (!p)
+ goto err;
+
br = p->br;
spin_lock(&br->lock);
--- a/net/bridge/netfilter/ebtables.c 2010-11-14 12:36:22.998445081 -0800
+++ b/net/bridge/netfilter/ebtables.c 2010-11-14 12:45:49.393153060 -0800
@@ -128,6 +128,7 @@ ebt_basic_match(const struct ebt_entry *
const struct net_device *in, const struct net_device *out)
{
const struct ethhdr *h = eth_hdr(skb);
+ const struct net_bridge_port *p;
__be16 ethproto;
int verdict, i;
@@ -148,13 +149,11 @@ ebt_basic_match(const struct ebt_entry *
if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT))
return 1;
/* rcu_read_lock()ed by nf_hook_slow */
- if (in && br_port_exists(in) &&
- FWINV2(ebt_dev_check(e->logical_in, br_port_get_rcu(in)->br->dev),
- EBT_ILOGICALIN))
+ if (in && (p = br_port_get_rcu(in)) != NULL &&
+ FWINV2(ebt_dev_check(e->logical_in, p->br->dev), EBT_ILOGICALIN))
return 1;
- if (out && br_port_exists(out) &&
- FWINV2(ebt_dev_check(e->logical_out, br_port_get_rcu(out)->br->dev),
- EBT_ILOGICALOUT))
+ if (out && (p = br_port_get_rcu(out)) != NULL &&
+ FWINV2(ebt_dev_check(e->logical_out, p->br->dev), EBT_ILOGICALOUT))
return 1;
if (e->bitmask & EBT_SOURCEMAC) {
--- a/net/bridge/br_fdb.c 2010-11-14 12:36:23.022448019 -0800
+++ b/net/bridge/br_fdb.c 2010-11-14 12:44:55.670987817 -0800
@@ -238,15 +238,18 @@ struct net_bridge_fdb_entry *__br_fdb_ge
int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
{
struct net_bridge_fdb_entry *fdb;
+ struct net_bridge_port *port;
int ret;
- if (!br_port_exists(dev))
- return 0;
-
rcu_read_lock();
- fdb = __br_fdb_get(br_port_get_rcu(dev)->br, addr);
- ret = fdb && fdb->dst->dev != dev &&
- fdb->dst->state == BR_STATE_FORWARDING;
+ port = br_port_get_rcu(dev);
+ if (!port)
+ ret = 0;
+ else {
+ fdb = __br_fdb_get(port->br, addr);
+ ret = fdb && fdb->dst->dev != dev &&
+ fdb->dst->state == BR_STATE_FORWARDING;
+ }
rcu_read_unlock();
return ret;
--- a/net/bridge/br_notify.c 2010-11-14 12:36:23.034449489 -0800
+++ b/net/bridge/br_notify.c 2010-11-14 12:44:55.670987817 -0800
@@ -32,7 +32,7 @@ struct notifier_block br_device_notifier
static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
{
struct net_device *dev = ptr;
- struct net_bridge_port *p = br_port_get(dev);
+ struct net_bridge_port *p;
struct net_bridge *br;
int err;
--- a/net/bridge/br_private.h 2010-11-14 12:44:07.257410977 -0800
+++ b/net/bridge/br_private.h 2010-11-14 12:44:55.670987817 -0800
@@ -151,11 +151,21 @@ struct net_bridge_port
#endif
};
-#define br_port_get_rcu(dev) \
- ((struct net_bridge_port *) rcu_dereference(dev->rx_handler_data))
-#define br_port_get(dev) ((struct net_bridge_port *) dev->rx_handler_data)
#define br_port_exists(dev) (dev->priv_flags & IFF_BRIDGE_PORT)
+static inline struct net_bridge_port *br_port_get_rcu(const struct net_device *dev)
+{
+ return br_port_exists(dev) ?
+ rcu_dereference(dev->rx_handler_data) : NULL;
+}
+
+static inline struct net_bridge_port *br_port_get(struct net_device *dev)
+{
+ return br_port_exists(dev) ? dev->rx_handler_data : NULL;
+}
+
+#define br_port_get(dev) ((struct net_bridge_port *) dev->rx_handler_data)
+
struct br_cpu_netstats {
u64 rx_packets;
u64 rx_bytes;
--- a/net/bridge/br_if.c 2010-11-14 12:36:23.046450958 -0800
+++ b/net/bridge/br_if.c 2010-11-14 12:44:55.670987817 -0800
@@ -475,11 +475,8 @@ int br_del_if(struct net_bridge *br, str
{
struct net_bridge_port *p;
- if (!br_port_exists(dev))
- return -EINVAL;
-
p = br_port_get(dev);
- if (p->br != br)
+ if (!p || p->br != br)
return -EINVAL;
del_nbp(p);
--- a/net/bridge/br_netlink.c 2010-11-14 12:36:23.062452917 -0800
+++ b/net/bridge/br_netlink.c 2010-11-14 12:44:55.670987817 -0800
@@ -119,11 +119,13 @@ static int br_dump_ifinfo(struct sk_buff
idx = 0;
for_each_netdev(net, dev) {
+ struct net_bridge_port *port = br_port_get(dev);
+
/* not a bridge port */
- if (!br_port_exists(dev) || idx < cb->args[0])
+ if (!port || idx < cb->args[0])
goto skip;
- if (br_fill_ifinfo(skb, br_port_get(dev),
+ if (br_fill_ifinfo(skb, port,
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, RTM_NEWLINK,
NLM_F_MULTI) < 0)
@@ -169,9 +171,9 @@ static int br_rtm_setlink(struct sk_buff
if (!dev)
return -ENODEV;
- if (!br_port_exists(dev))
- return -EINVAL;
p = br_port_get(dev);
+ if (!p)
+ return -EINVAL;
/* if kernel STP is running, don't allow changes */
if (p->br->stp_enabled == BR_KERNEL_STP)
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH 5/5] bridge: add RCU annotations to bridge port lookup
2010-11-14 21:12 [PATCH 0/5] bridge: RCU annotation and cleanup Stephen Hemminger
` (3 preceding siblings ...)
2010-11-14 21:12 ` [PATCH 4/5] bridge: fix RCU races with bridge port Stephen Hemminger
@ 2010-11-14 21:12 ` Stephen Hemminger
2010-11-15 12:23 ` [PATCH 0/5] bridge: RCU annotation and cleanup Tetsuo Handa
5 siblings, 0 replies; 9+ messages in thread
From: Stephen Hemminger @ 2010-11-14 21:12 UTC (permalink / raw)
To: David Miller, Eric Dumazet; +Cc: netdev, bridge
[-- Attachment #1: bridgeX.patch --]
[-- Type: text/plain, Size: 2502 bytes --]
From: Eric Dumazet <eric.dumazet@gmail.com>
Add modern __rcu annotations to bridge code, to reduce sparse errors,
and self document code.
(CONFIG_SPARSE_RCU_POINTER=y)
br_port_get() split int br_port_get_rtnl() and br_port_get_rcu()
to make clear RTNL is held.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
---
net/bridge/br_if.c | 2 +-
net/bridge/br_netlink.c | 4 ++--
net/bridge/br_notify.c | 4 ++--
net/bridge/br_private.h | 9 +++++----
4 files changed, 10 insertions(+), 9 deletions(-)
--- a/net/bridge/br_netlink.c 2010-11-14 12:24:35.000000000 -0800
+++ b/net/bridge/br_netlink.c 2010-11-14 12:26:47.859892139 -0800
@@ -119,7 +119,7 @@ static int br_dump_ifinfo(struct sk_buff
idx = 0;
for_each_netdev(net, dev) {
- struct net_bridge_port *port = br_port_get(dev);
+ struct net_bridge_port *port = br_port_get_rtnl(dev);
/* not a bridge port */
if (!port || idx < cb->args[0])
@@ -171,7 +171,7 @@ static int br_rtm_setlink(struct sk_buff
if (!dev)
return -ENODEV;
- p = br_port_get(dev);
+ p = br_port_get_rtnl(dev);
if (!p)
return -EINVAL;
--- a/net/bridge/br_private.h 2010-11-14 12:25:44.600853008 -0800
+++ b/net/bridge/br_private.h 2010-11-14 12:33:23.880986098 -0800
@@ -159,9 +159,10 @@ static inline struct net_bridge_port *br
rcu_dereference(dev->rx_handler_data) : NULL;
}
-static inline struct net_bridge_port *br_port_get(struct net_device *dev)
+static inline struct net_bridge_port *br_port_get_rtnl(struct net_device *dev)
{
- return br_port_exists(dev) ? dev->rx_handler_data : NULL;
+ return br_port_exists(dev) ?
+ rtnl_dereference(dev->rx_handler_data) : NULL;
}
#define br_port_get(dev) ((struct net_bridge_port *) dev->rx_handler_data)
--- a/net/bridge/br_if.c 2010-11-14 12:23:34.000000000 -0800
+++ b/net/bridge/br_if.c 2010-11-14 12:27:24.267934764 -0800
@@ -475,7 +475,7 @@ int br_del_if(struct net_bridge *br, str
{
struct net_bridge_port *p;
- p = br_port_get(dev);
+ p = br_port_get_rtnl(dev);
if (!p || p->br != br)
return -EINVAL;
--- a/net/bridge/br_notify.c 2010-11-14 12:30:46.250267273 -0800
+++ b/net/bridge/br_notify.c 2010-11-14 12:31:11.749076964 -0800
@@ -37,10 +37,10 @@ static int br_device_event(struct notifi
int err;
/* not a port of a bridge */
- if (!br_port_exists(dev))
+ p = br_port_get_rtnl(dev);
+ if (!p)
return NOTIFY_DONE;
- p = br_port_get(dev);
br = p->br;
switch (event) {
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH 0/5] bridge: RCU annotation and cleanup
2010-11-14 21:12 [PATCH 0/5] bridge: RCU annotation and cleanup Stephen Hemminger
` (4 preceding siblings ...)
2010-11-14 21:12 ` [PATCH 5/5] bridge: add RCU annotations to bridge port lookup Stephen Hemminger
@ 2010-11-15 12:23 ` Tetsuo Handa
2010-11-15 13:33 ` Eric Dumazet
2010-11-15 16:19 ` Stephen Hemminger
5 siblings, 2 replies; 9+ messages in thread
From: Tetsuo Handa @ 2010-11-15 12:23 UTC (permalink / raw)
To: shemminger, davem, eric.dumazet; +Cc: netdev, bridge
Stephen Hemminger wrote:
> This is a split up of what Eric did with a couple of small changes and additions.
Something seems to be wrong with this patchset.
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
> @@ -173,8 +177,8 @@ forward:
> switch (p->state) {
> case BR_STATE_FORWARDING:
> rhook = rcu_dereference(br_should_route_hook);
> - if (rhook != NULL) {
> - if (rhook(skb))
> + if (rhook) {
> + if ((*rhook)(skb))
Is *rhook != NULL guaranteed when rhook != NULL?
> return skb;
> dest = eth_hdr(skb)->h_dest;
> }
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c
> @@ -242,7 +242,7 @@ static void br_multicast_flood(struct ne
> if ((unsigned long)lport >= (unsigned long)port)
> p = rcu_dereference(p->next);
> if ((unsigned long)rport >= (unsigned long)port)
> - rp = rcu_dereference(rp->next);
> + rp = rcu_dereference(hlist_next_rcu(rp->next));
I think this one is hlist_next_rcu(rp).
> }
>
> if (!prev)
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
> @@ -475,11 +475,8 @@ int br_del_if(struct net_bridge *br, str
> {
> struct net_bridge_port *p;
>
> - if (!br_port_exists(dev))
> - return -EINVAL;
> -
> p = br_port_get(dev);
Don't you need to use br_port_get_rtnl()? (I don't know.)
> - if (p->br != br)
> + if (!p || p->br != br)
> return -EINVAL;
>
> del_nbp(p);
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
> @@ -169,9 +171,9 @@ static int br_rtm_setlink(struct sk_buff
> if (!dev)
> return -ENODEV;
>
> - if (!br_port_exists(dev))
> - return -EINVAL;
> p = br_port_get(dev);
Don't you need to use br_port_get_rtnl()? (I don't know.)
> + if (!p)
> + return -EINVAL;
>
> /* if kernel STP is running, don't allow changes */
> if (p->br->stp_enabled == BR_KERNEL_STP)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
> @@ -151,11 +151,21 @@ struct net_bridge_port
> #endif
> };
>
> -#define br_port_get_rcu(dev) \
> - ((struct net_bridge_port *) rcu_dereference(dev->rx_handler_data))
> -#define br_port_get(dev) ((struct net_bridge_port *) dev->rx_handler_data)
> #define br_port_exists(dev) (dev->priv_flags & IFF_BRIDGE_PORT)
>
> +static inline struct net_bridge_port *br_port_get_rcu(const struct net_device *dev)
> +{
> + return br_port_exists(dev) ?
> + rcu_dereference(dev->rx_handler_data) : NULL;
> +}
> +
> +static inline struct net_bridge_port *br_port_get(struct net_device *dev)
> +{
> + return br_port_exists(dev) ? dev->rx_handler_data : NULL;
> +}
> +
> +#define br_port_get(dev) ((struct net_bridge_port *) dev->rx_handler_data)
Why are you defining br_port_get() twice, once as macro and once as inlined
function?
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH 0/5] bridge: RCU annotation and cleanup
2010-11-15 12:23 ` [PATCH 0/5] bridge: RCU annotation and cleanup Tetsuo Handa
@ 2010-11-15 13:33 ` Eric Dumazet
2010-11-15 16:19 ` Stephen Hemminger
1 sibling, 0 replies; 9+ messages in thread
From: Eric Dumazet @ 2010-11-15 13:33 UTC (permalink / raw)
To: Tetsuo Handa; +Cc: shemminger, davem, netdev, bridge
Le lundi 15 novembre 2010 à 21:23 +0900, Tetsuo Handa a écrit :
> Stephen Hemminger wrote:
> > This is a split up of what Eric did with a couple of small changes and additions.
> Something seems to be wrong with this patchset.
>
> --- a/net/bridge/br_input.c
> +++ b/net/bridge/br_input.c
> > @@ -173,8 +177,8 @@ forward:
> > switch (p->state) {
> > case BR_STATE_FORWARDING:
> > rhook = rcu_dereference(br_should_route_hook);
> > - if (rhook != NULL) {
> > - if (rhook(skb))
> > + if (rhook) {
> > + if ((*rhook)(skb))
>
> Is *rhook != NULL guaranteed when rhook != NULL?
Its the C standard convention, we call function pointed by rhook, not
*rhook.
$ cat func.c
typedef int (*hook_t)(int a1, int a2);
hook_t *hook;
int foo(int a1, int a2)
{
hook_t *handler = hook;
if (handler)
return handler(a1, a2);
return 0;
}
$ gcc -O2 -c func.c
func.c: In function ‘foo’:
func.c:10:17: error: called object ‘handler’ is not a function
Now, if we use (*handler), it works :
$ cat func.c
typedef int (*hook_t)(int a1, int a2);
hook_t *hook;
int foo(int a1, int a2)
{
hook_t *handler = hook;
if (handler)
return (*handler)(a1, a2);
return 0;
}
$ gcc -O2 -c func.c
$
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH 0/5] bridge: RCU annotation and cleanup
2010-11-15 12:23 ` [PATCH 0/5] bridge: RCU annotation and cleanup Tetsuo Handa
2010-11-15 13:33 ` Eric Dumazet
@ 2010-11-15 16:19 ` Stephen Hemminger
1 sibling, 0 replies; 9+ messages in thread
From: Stephen Hemminger @ 2010-11-15 16:19 UTC (permalink / raw)
To: Tetsuo Handa; +Cc: davem, eric.dumazet, netdev, bridge
On Mon, 15 Nov 2010 21:23:37 +0900
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> wrote:
> > + rp = rcu_dereference(hlist_next_rcu(rp->next));
>
> I think this one is hlist_next_rcu(rp).
Yes, you are correct.
--
^ permalink raw reply [flat|nested] 9+ messages in thread