From 0751272880f3a0c74c786ecfaba2b3d98748482f Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Sat, 15 Aug 2015 11:00:32 +0200 Subject: [PATCH] ieee802154: 6lowpan: fix packet layer registration This patch fixes 802.15.4 packet layer registration when mutliple lowpan interfaces will be added. We need to register the packet layer at the first lowpan interface and deregister it at the last interface. This done by open_count variable which is protected by rtnl. Additional do a quiet fix by adding dev_put(real_dev) when netdev registration fails, which fix the refcount for the wpan dev. Signed-off-by: Alexander Aring Signed-off-by: Marcel Holtmann --- net/ieee802154/6lowpan/core.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c index 180e9f5f86c3..27c25ad935b4 100644 --- a/net/ieee802154/6lowpan/core.c +++ b/net/ieee802154/6lowpan/core.c @@ -52,6 +52,8 @@ #include "6lowpan_i.h" +static int open_count; + static struct header_ops lowpan_header_ops = { .create = lowpan_header_create, }; @@ -141,12 +143,18 @@ static int lowpan_newlink(struct net *src_net, struct net_device *dev, lowpan_netdev_setup(dev, LOWPAN_LLTYPE_IEEE802154); ret = register_netdevice(dev); - if (ret >= 0) { - real_dev->ieee802154_ptr->lowpan_dev = dev; - lowpan_rx_init(); + if (ret < 0) { + dev_put(real_dev); + return ret; } - return ret; + real_dev->ieee802154_ptr->lowpan_dev = dev; + if (!open_count) + lowpan_rx_init(); + + open_count++; + + return 0; } static void lowpan_dellink(struct net_device *dev, struct list_head *head) @@ -156,7 +164,11 @@ static void lowpan_dellink(struct net_device *dev, struct list_head *head) ASSERT_RTNL(); - lowpan_rx_exit(); + open_count--; + + if (!open_count) + lowpan_rx_exit(); + real_dev->ieee802154_ptr->lowpan_dev = NULL; unregister_netdevice(dev); dev_put(real_dev); -- 2.20.1