From: Ying Xue Date: Wed, 15 Jan 2014 02:23:42 +0000 (+0800) Subject: batman-adv: use __dev_get_by_index instead of dev_get_by_index to find interface X-Git-Tag: next-20140116~67^2~7^2~3 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=16b77695ed8fa158be864ee448a9ef4c78457c14;p=karo-tx-linux.git batman-adv: use __dev_get_by_index instead of dev_get_by_index to find interface The following call chains indicate that batadv_is_on_batman_iface() is always under rtnl_lock protection as call_netdevice_notifier() is protected by rtnl_lock. So if __dev_get_by_index() rather than dev_get_by_index() is used to find interface handler in it, this would help us avoid to change interface reference counter. call_netdevice_notifier() batadv_hard_if_event() batadv_hardif_add_interface() batadv_is_valid_iface() batadv_is_on_batman_iface() Cc: Antonio Quartulli Signed-off-by: Ying Xue Acked-by: Antonio Quartulli Signed-off-by: David S. Miller --- diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 1b12573bcf83..3d417d3641c6 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -87,15 +87,13 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev) return false; /* recurse over the parent device */ - parent_dev = dev_get_by_index(&init_net, net_dev->iflink); + parent_dev = __dev_get_by_index(&init_net, net_dev->iflink); /* if we got a NULL parent_dev there is something broken.. */ if (WARN(!parent_dev, "Cannot find parent device")) return false; ret = batadv_is_on_batman_iface(parent_dev); - if (parent_dev) - dev_put(parent_dev); return ret; }