mac80211: add interface list lock
Using only the RTNL has a number of problems, most notably that
ieee80211_iterate_active_interfaces() and other interface list
traversals cannot be done from the internal workqueue because it
needs to be flushed under the RTNL.
This patch introduces a new mutex that protects the interface list
against modifications. A more detailed explanation is part of the
code change.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 210dfe3..a109c06 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -758,6 +758,7 @@
local->hw.conf.radio_enabled = true;
INIT_LIST_HEAD(&local->interfaces);
+ mutex_init(&local->iflist_mtx);
spin_lock_init(&local->key_lock);
@@ -1008,6 +1009,8 @@
{
struct ieee80211_local *local = hw_to_local(hw);
+ mutex_destroy(&local->iflist_mtx);
+
wiphy_free(local->hw.wiphy);
}
EXPORT_SYMBOL(ieee80211_free_hw);