--- /dev/null
+From 4c8a9d4bfaf7dbc7d2168494904d79d22cc01db7 Mon Sep 17 00:00:00 2001
+From: Johannes Berg <johannes.berg@intel.com>
+Date: Fri, 24 May 2013 01:06:09 +0200
+Subject: mac80211: close AP_VLAN interfaces before unregistering all
+
+From: Johannes Berg <johannes.berg@intel.com>
+
+commit 4c8a9d4bfaf7dbc7d2168494904d79d22cc01db7 upstream.
+
+Since Eric's commit efe117ab8 ("Speedup ieee80211_remove_interfaces")
+there's a bug in mac80211 when it unregisters with AP_VLAN interfaces
+up. If the AP_VLAN interface was registered after the AP it belongs
+to (which is the typical case) and then we get into this code path,
+unregister_netdevice_many() will crash because it isn't prepared to
+deal with interfaces being closed in the middle of it. Exactly this
+happens though, because we iterate the list, find the AP master this
+AP_VLAN belongs to and dev_close() the dependent VLANs. After this,
+unregister_netdevice_many() won't pick up the fact that the AP_VLAN
+is already down and will do it again, causing a crash.
+
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+Cc: Eric Dumazet <eric.dumazet@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ net/mac80211/iface.c | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+--- a/net/mac80211/iface.c
++++ b/net/mac80211/iface.c
+@@ -1380,6 +1380,15 @@ void ieee80211_recalc_idle(struct ieee80
+ {
+ u32 chg;
+
++ /*
++ * Close all AP_VLAN interfaces first, as otherwise they
++ * might be closed while the AP interface they belong to
++ * is closed, causing unregister_netdevice_many() to crash.
++ */
++ list_for_each_entry(sdata, &local->interfaces, list)
++ if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
++ dev_close(sdata->dev);
++
+ mutex_lock(&local->iflist_mtx);
+ chg = __ieee80211_recalc_idle(local);
+ mutex_unlock(&local->iflist_mtx);