From 93ec2c723e3f8a216dde2899aeb85c648672bc6b Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Thu, 26 Oct 2006 15:46:50 -0700 Subject: [PATCH] netpoll info leak After looking harder, Steve noticed that the netpoll beast leaked a little every time it shutdown for a nap. Not a big leak, but a nuisance kind of thing. He took out his refcount duct tape and patched the leak. It was overkill since there was already other locking in that area, but it looked clean and wouldn't attract fleas. Signed-off-by: Stephen Hemminger --- include/linux/netpoll.h | 1 + net/core/netpoll.c | 25 +++++++++++++++++++------ 2 files changed, 20 insertions(+), 6 deletions(-) diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h index 1efe60c5c00c..39845fc975f9 100644 --- a/include/linux/netpoll.h +++ b/include/linux/netpoll.h @@ -25,6 +25,7 @@ struct netpoll { }; struct netpoll_info { + atomic_t refcnt; spinlock_t poll_lock; int poll_owner; int tries; diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 4de62f1f4134..c66df2f45d26 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -658,8 +658,11 @@ int netpoll_setup(struct netpoll *np) npinfo->tries = MAX_RETRIES; spin_lock_init(&npinfo->rx_lock); skb_queue_head_init(&npinfo->arp_tx); - } else + atomic_set(&npinfo->refcnt, 1); + } else { npinfo = ndev->npinfo; + atomic_inc(&npinfo->refcnt); + } if (!ndev->poll_controller) { printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n", @@ -766,12 +769,22 @@ void netpoll_cleanup(struct netpoll *np) if (np->dev) { npinfo = np->dev->npinfo; - if (npinfo && npinfo->rx_np == np) { - spin_lock_irqsave(&npinfo->rx_lock, flags); - npinfo->rx_np = NULL; - npinfo->rx_flags &= ~NETPOLL_RX_ENABLED; - spin_unlock_irqrestore(&npinfo->rx_lock, flags); + if (npinfo) { + if (npinfo->rx_np == np) { + spin_lock_irqsave(&npinfo->rx_lock, flags); + npinfo->rx_np = NULL; + npinfo->rx_flags &= ~NETPOLL_RX_ENABLED; + spin_unlock_irqrestore(&npinfo->rx_lock, flags); + } + + np->dev->npinfo = NULL; + if (atomic_dec_and_test(&npinfo->refcnt)) { + skb_queue_purge(&npinfo->arp_tx); + + kfree(npinfo); + } } + dev_put(np->dev); }