From f17f5c91ae3bfeb5cfc37fa132a5fdfceb8927be Mon Sep 17 00:00:00 2001 From: Herbert Xu <herbert@gondor.apana.org.au> Date: Wed, 14 Jan 2009 14:36:12 -0800 Subject: gro: Check for GSO packets and packets with frag_list As GRO cannot be applied to packets with frag_list we need to make sure that we reject such packets if they are fed to us, e.g., through a tunnel device. Also there is no point in applying GRO on GSO packets so they too should be rejected. This allows GRO to be used in virtio-net which may produce GSO packets directly but may still benefit from GRO if the other end of it doesn't support GSO. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/dev.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index b715a55cccc..7dec715293b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2392,6 +2392,9 @@ int dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) if (!(skb->dev->features & NETIF_F_GRO)) goto normal; + if (skb_is_gso(skb) || skb_shinfo(skb)->frag_list) + goto normal; + rcu_read_lock(); list_for_each_entry_rcu(ptype, head, list) { struct sk_buff *p; -- cgit v1.2.3-70-g09d2 From f557206800801410c30e53ce7a27219b2c4cf0ba Mon Sep 17 00:00:00 2001 From: Herbert Xu <herbert@gondor.apana.org.au> Date: Wed, 14 Jan 2009 20:40:03 -0800 Subject: gro: Fix page ref count for skbs freed normally When an skb with page frags is merged into an existing one, we cannibalise its reference count. This is OK when the skb is reused because we set nr_frags to zero in that case. However, for the case where the skb is freed through kfree_skb, we didn't clear nr_frags which causes the page to be freed prematurely. This is fixed by moving the skb resetting into skb_gro_receive. Reported-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/dev.c | 6 ------ net/core/skbuff.c | 6 ++++++ 2 files changed, 6 insertions(+), 6 deletions(-) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index 7dec715293b..60377b6c0a8 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2491,12 +2491,6 @@ EXPORT_SYMBOL(napi_gro_receive); void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) { - skb_shinfo(skb)->nr_frags = 0; - - skb->len -= skb->data_len; - skb->truesize -= skb->data_len; - skb->data_len = 0; - __skb_pull(skb, skb_headlen(skb)); skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb)); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 5110b359c75..65eac773903 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2602,6 +2602,12 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t)); skb_shinfo(p)->nr_frags += skb_shinfo(skb)->nr_frags; + skb_shinfo(skb)->nr_frags = 0; + + skb->truesize -= skb->data_len; + skb->len -= skb->data_len; + skb->data_len = 0; + NAPI_GRO_CB(skb)->free = 1; goto done; } -- cgit v1.2.3-70-g09d2 From 937f1ba56b4be37d9e2ad77412f95048662058d2 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt <benh@kernel.crashing.org> Date: Wed, 14 Jan 2009 21:05:05 -0800 Subject: net: Add init_dummy_netdev() and fix EMAC driver using it This adds an init_dummy_netdev() function that gets a network device structure (allocation and lifetime entirely under caller's control) and initialize the minimum amount of fields so it can be used to schedule NAPI polls without registering a full blown interface. This is to be used by drivers that need to tie several hardware interfaces to a single NAPI poll scheduler due to HW limitations. It also updates the ibm_newemac driver to use that, this fixing the oops on 2.6.29 due to passing NULL as "dev" to netif_napi_add() Symbol is exported GPL only a I don't think we want binary drivers doing that sort of acrobatics (if we want them at all). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- drivers/net/ibm_newemac/mal.c | 4 +++- drivers/net/ibm_newemac/mal.h | 2 ++ include/linux/netdevice.h | 3 +++ net/core/dev.c | 39 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 47 insertions(+), 1 deletion(-) (limited to 'net/core/dev.c') diff --git a/drivers/net/ibm_newemac/mal.c b/drivers/net/ibm_newemac/mal.c index ecf9798987f..2a2fc17b287 100644 --- a/drivers/net/ibm_newemac/mal.c +++ b/drivers/net/ibm_newemac/mal.c @@ -613,7 +613,9 @@ static int __devinit mal_probe(struct of_device *ofdev, INIT_LIST_HEAD(&mal->list); spin_lock_init(&mal->lock); - netif_napi_add(NULL, &mal->napi, mal_poll, + init_dummy_netdev(&mal->dummy_dev); + + netif_napi_add(&mal->dummy_dev, &mal->napi, mal_poll, CONFIG_IBM_NEW_EMAC_POLL_WEIGHT); /* Load power-on reset defaults */ diff --git a/drivers/net/ibm_newemac/mal.h b/drivers/net/ibm_newemac/mal.h index 2f0a8736084..9ededfbf072 100644 --- a/drivers/net/ibm_newemac/mal.h +++ b/drivers/net/ibm_newemac/mal.h @@ -214,6 +214,8 @@ struct mal_instance { int index; spinlock_t lock; + struct net_device dummy_dev; + unsigned int features; }; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4647604c7ca..ec54785d34f 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -795,6 +795,7 @@ struct net_device NETREG_UNREGISTERING, /* called unregister_netdevice */ NETREG_UNREGISTERED, /* completed unregister todo */ NETREG_RELEASED, /* called free_netdev */ + NETREG_DUMMY, /* dummy device for NAPI poll */ } reg_state; /* Called from unregister, can be used to call free_netdev */ @@ -1077,6 +1078,8 @@ extern void free_netdev(struct net_device *dev); extern void synchronize_net(void); extern int register_netdevice_notifier(struct notifier_block *nb); extern int unregister_netdevice_notifier(struct notifier_block *nb); +extern int init_dummy_netdev(struct net_device *dev); + extern int call_netdevice_notifiers(unsigned long val, struct net_device *dev); extern struct net_device *dev_get_by_index(struct net *net, int ifindex); extern struct net_device *__dev_get_by_index(struct net *net, int ifindex); diff --git a/net/core/dev.c b/net/core/dev.c index 60377b6c0a8..8d675975d85 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4430,6 +4430,45 @@ err_uninit: goto out; } +/** + * init_dummy_netdev - init a dummy network device for NAPI + * @dev: device to init + * + * This takes a network device structure and initialize the minimum + * amount of fields so it can be used to schedule NAPI polls without + * registering a full blown interface. This is to be used by drivers + * that need to tie several hardware interfaces to a single NAPI + * poll scheduler due to HW limitations. + */ +int init_dummy_netdev(struct net_device *dev) +{ + /* Clear everything. Note we don't initialize spinlocks + * are they aren't supposed to be taken by any of the + * NAPI code and this dummy netdev is supposed to be + * only ever used for NAPI polls + */ + memset(dev, 0, sizeof(struct net_device)); + + /* make sure we BUG if trying to hit standard + * register/unregister code path + */ + dev->reg_state = NETREG_DUMMY; + + /* initialize the ref count */ + atomic_set(&dev->refcnt, 1); + + /* NAPI wants this */ + INIT_LIST_HEAD(&dev->napi_list); + + /* a dummy interface is started by default */ + set_bit(__LINK_STATE_PRESENT, &dev->state); + set_bit(__LINK_STATE_START, &dev->state); + + return 0; +} +EXPORT_SYMBOL_GPL(init_dummy_netdev); + + /** * register_netdev - register a network device * @dev: device to register -- cgit v1.2.3-70-g09d2