| Message ID | 20100727112630.5a5ce84b@nehalam |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Tue, 2010-07-27 at 11:26 -0700, Stephen Hemminger wrote: > -/* net device transmit always called with no BH (preempt_disabled) */ > +/* net device transmit always called with no BH disabled */ "no BH disabled"? > @@ -48,6 +48,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff * > skb_reset_mac_header(skb); > skb_pull(skb, ETH_HLEN); > > + rcu_read_lock(); > if (is_multicast_ether_addr(dest)) { > if (unlikely(netpoll_tx_running(dev))) { > br_flood_deliver(br, skb); > @@ -67,6 +68,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff * > br_flood_deliver(br, skb); > > out: > + rcu_read_unlock(); > return NETDEV_TX_OK; > } > > --- a/net/bridge/br_fdb.c 2010-07-27 11:18:30.815320981 -0700 > +++ b/net/bridge/br_fdb.c 2010-07-27 11:18:59.597710975 -0700 > @@ -214,7 +214,7 @@ void br_fdb_delete_by_port(struct net_br > spin_unlock_bh(&br->hash_lock); > } > > -/* No locking or refcounting, assumes caller has no preempt (rcu_read_lock) */ > +/* No locking or refcounting, assumes caller has rcu_read_lock */ > struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br, > const unsigned char *addr) > { > --- a/net/bridge/br_input.c 2010-07-27 11:19:05.266181492 -0700 > +++ b/net/bridge/br_input.c 2010-07-27 11:19:29.148163149 -0700 > @@ -39,7 +39,7 @@ static int br_pass_frame_up(struct sk_bu > netif_receive_skb); > } > > -/* note: already called with rcu_read_lock (preempt_disabled) */ > +/* note: already called with rcu_read_lock */ > int br_handle_frame_finish(struct sk_buff *skb) > { > const unsigned char *dest = eth_hdr(skb)->h_dest; > @@ -110,7 +110,7 @@ drop: > goto out; > } > > -/* note: already called with rcu_read_lock (preempt_disabled) */ > +/* note: already called with rcu_read_lock */ > static int br_handle_local_finish(struct sk_buff *skb) > { > struct net_bridge_port *p = br_port_get_rcu(skb->dev); > @@ -133,8 +133,7 @@ static inline int is_link_local(const un > > /* > * Return NULL if skb is handled > - * note: already called with rcu_read_lock (preempt_disabled) from > - * netif_receive_skb > + * note: already called with rcu_read_lock from netif_receive_skb > */ > struct sk_buff *br_handle_frame(struct sk_buff *skb) > { > --- a/net/bridge/br_stp_bpdu.c 2010-07-27 11:19:34.092573294 -0700 > +++ b/net/bridge/br_stp_bpdu.c 2010-07-27 11:19:40.725123403 -0700 > @@ -131,7 +131,7 @@ void br_send_tcn_bpdu(struct net_bridge_ > /* > * Called from llc. > * > - * NO locks, but rcu_read_lock (preempt_disabled) > + * NO locks, but rcu_read_lock > */ > void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb, > struct net_device *dev) > Did you want me to test the patch? johannes -- 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 Tue, 27 Jul 2010 22:14:39 +0200 Johannes Berg <johannes@sipsolutions.net> wrote: > On Tue, 2010-07-27 at 11:26 -0700, Stephen Hemminger wrote: > > > -/* net device transmit always called with no BH (preempt_disabled) */ > > +/* net device transmit always called with no BH disabled */ > > "no BH disabled"? > > > @@ -48,6 +48,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff * > > skb_reset_mac_header(skb); > > skb_pull(skb, ETH_HLEN); > > > > + rcu_read_lock(); > > if (is_multicast_ether_addr(dest)) { > > if (unlikely(netpoll_tx_running(dev))) { > > br_flood_deliver(br, skb); > > @@ -67,6 +68,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff * > > br_flood_deliver(br, skb); > > > > out: > > + rcu_read_unlock(); > > return NETDEV_TX_OK; > > } > > > > --- a/net/bridge/br_fdb.c 2010-07-27 11:18:30.815320981 -0700 > > +++ b/net/bridge/br_fdb.c 2010-07-27 11:18:59.597710975 -0700 > > @@ -214,7 +214,7 @@ void br_fdb_delete_by_port(struct net_br > > spin_unlock_bh(&br->hash_lock); > > } > > > > -/* No locking or refcounting, assumes caller has no preempt (rcu_read_lock) */ > > +/* No locking or refcounting, assumes caller has rcu_read_lock */ > > struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br, > > const unsigned char *addr) > > { > > --- a/net/bridge/br_input.c 2010-07-27 11:19:05.266181492 -0700 > > +++ b/net/bridge/br_input.c 2010-07-27 11:19:29.148163149 -0700 > > @@ -39,7 +39,7 @@ static int br_pass_frame_up(struct sk_bu > > netif_receive_skb); > > } > > > > -/* note: already called with rcu_read_lock (preempt_disabled) */ > > +/* note: already called with rcu_read_lock */ > > int br_handle_frame_finish(struct sk_buff *skb) > > { > > const unsigned char *dest = eth_hdr(skb)->h_dest; > > @@ -110,7 +110,7 @@ drop: > > goto out; > > } > > > > -/* note: already called with rcu_read_lock (preempt_disabled) */ > > +/* note: already called with rcu_read_lock */ > > static int br_handle_local_finish(struct sk_buff *skb) > > { > > struct net_bridge_port *p = br_port_get_rcu(skb->dev); > > @@ -133,8 +133,7 @@ static inline int is_link_local(const un > > > > /* > > * Return NULL if skb is handled > > - * note: already called with rcu_read_lock (preempt_disabled) from > > - * netif_receive_skb > > + * note: already called with rcu_read_lock from netif_receive_skb > > */ > > struct sk_buff *br_handle_frame(struct sk_buff *skb) > > { > > --- a/net/bridge/br_stp_bpdu.c 2010-07-27 11:19:34.092573294 -0700 > > +++ b/net/bridge/br_stp_bpdu.c 2010-07-27 11:19:40.725123403 -0700 > > @@ -131,7 +131,7 @@ void br_send_tcn_bpdu(struct net_bridge_ > > /* > > * Called from llc. > > * > > - * NO locks, but rcu_read_lock (preempt_disabled) > > + * NO locks, but rcu_read_lock > > */ > > void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb, > > struct net_device *dev) > > > > Did you want me to test the patch? Yes please, I can make sure it works, but not that it gets rid of your error
On Tue, 2010-07-27 at 13:42 -0700, Stephen Hemminger wrote: > > Did you want me to test the patch? > > Yes please, I can make sure it works, but not that it gets rid > of your error Testing now, but it didn't quite apply cleanly on 2.6.35-rc. johannes -- 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 Tue, 2010-07-27 at 13:42 -0700, Stephen Hemminger wrote: > > > > Did you want me to test the patch? > > Yes please, I can make sure it works, but not that it gets rid > of your error Yes, it fixed it, thanks. johannes -- 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
From: Johannes Berg <johannes@sipsolutions.net> Date: Wed, 28 Jul 2010 09:33:51 +0200 > On Tue, 2010-07-27 at 13:42 -0700, Stephen Hemminger wrote: > >> > >> > Did you want me to test the patch? >> >> Yes please, I can make sure it works, but not that it gets rid >> of your error > > Yes, it fixed it, thanks. I fixed up the comment thinko Johannes noticed, added a tested-by tag, and applied this to net-2.6 Thanks! -- 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
--- a/net/bridge/br_device.c 2010-07-27 08:57:43.169399349 -0700 +++ b/net/bridge/br_device.c 2010-07-27 11:18:51.677053426 -0700 @@ -22,7 +22,7 @@ #include <asm/uaccess.h> #include "br_private.h" -/* net device transmit always called with no BH (preempt_disabled) */ +/* net device transmit always called with no BH disabled */ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev) { struct net_bridge *br = netdev_priv(dev); @@ -48,6 +48,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff * skb_reset_mac_header(skb); skb_pull(skb, ETH_HLEN); + rcu_read_lock(); if (is_multicast_ether_addr(dest)) { if (unlikely(netpoll_tx_running(dev))) { br_flood_deliver(br, skb); @@ -67,6 +68,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff * br_flood_deliver(br, skb); out: + rcu_read_unlock(); return NETDEV_TX_OK; } --- a/net/bridge/br_fdb.c 2010-07-27 11:18:30.815320981 -0700 +++ b/net/bridge/br_fdb.c 2010-07-27 11:18:59.597710975 -0700 @@ -214,7 +214,7 @@ void br_fdb_delete_by_port(struct net_br spin_unlock_bh(&br->hash_lock); } -/* No locking or refcounting, assumes caller has no preempt (rcu_read_lock) */ +/* No locking or refcounting, assumes caller has rcu_read_lock */ struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br, const unsigned char *addr) { --- a/net/bridge/br_input.c 2010-07-27 11:19:05.266181492 -0700 +++ b/net/bridge/br_input.c 2010-07-27 11:19:29.148163149 -0700 @@ -39,7 +39,7 @@ static int br_pass_frame_up(struct sk_bu netif_receive_skb); } -/* note: already called with rcu_read_lock (preempt_disabled) */ +/* note: already called with rcu_read_lock */ int br_handle_frame_finish(struct sk_buff *skb) { const unsigned char *dest = eth_hdr(skb)->h_dest; @@ -110,7 +110,7 @@ drop: goto out; } -/* note: already called with rcu_read_lock (preempt_disabled) */ +/* note: already called with rcu_read_lock */ static int br_handle_local_finish(struct sk_buff *skb) { struct net_bridge_port *p = br_port_get_rcu(skb->dev); @@ -133,8 +133,7 @@ static inline int is_link_local(const un /* * Return NULL if skb is handled - * note: already called with rcu_read_lock (preempt_disabled) from - * netif_receive_skb + * note: already called with rcu_read_lock from netif_receive_skb */ struct sk_buff *br_handle_frame(struct sk_buff *skb) { --- a/net/bridge/br_stp_bpdu.c 2010-07-27 11:19:34.092573294 -0700 +++ b/net/bridge/br_stp_bpdu.c 2010-07-27 11:19:40.725123403 -0700 @@ -131,7 +131,7 @@ void br_send_tcn_bpdu(struct net_bridge_ /* * Called from llc. * - * NO locks, but rcu_read_lock (preempt_disabled) + * NO locks, but rcu_read_lock */ void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb, struct net_device *dev)
I think this is needed (untested)... ----- Subject: bridge: add rcu_read_lock on transmit Long ago, when bridge was converted to RCU, rcu lock was equivalent to having preempt disabled. RCU has changed a lot since then and bridge code was still assuming the since transmit was called with bottom half disabled, it was RCU safe. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> --- net/bridge/br_device.c | 4 +++- net/bridge/br_fdb.c | 2 +- net/bridge/br_input.c | 7 +++---- net/bridge/br_stp_bpdu.c | 2 +- 4 files changed, 8 insertions(+), 7 deletions(-) -- 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