Merge tag 'pci-v4.2-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

[linux-2.6-block.git] / net / mac80211 / iface.c

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index ed1edac143729cc117c1cb63c5519285acff13a7..553ac6dd4867480048aed3ca0d430948f928d3c7 100644 (file)
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1863,10 +1863,6 @@ void ieee80211_sdata_stop(struct ieee80211_sub_if_data *sdata)
        ieee80211_teardown_sdata(sdata);
 }
 
-/*
- * Remove all interfaces, may only be called at hardware unregistration
- * time because it doesn't do RCU-safe list removals.
- */
 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 {
        struct ieee80211_sub_if_data *sdata, *tmp;
@@ -1875,14 +1871,21 @@ void ieee80211_remove_interfaces(struct ieee80211_local *local)
 
        ASSERT_RTNL();
 
-       /*
-        * 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.
+       /* Before destroying the interfaces, make sure they're all stopped so
+        * that the hardware is stopped. Otherwise, the driver might still be
+        * iterating the interfaces during the shutdown, e.g. from a worker
+        * or from RX processing or similar, and if it does so (using atomic
+        * iteration) while we're manipulating the list, the iteration will
+        * crash.
+        *
+        * After this, the hardware should be stopped and the driver should
+        * have stopped all of its activities, so that we can do RCU-unaware
+        * manipulations of the interface list below.
         */
-       list_for_each_entry(sdata, &local->interfaces, list)
-               if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
-                       dev_close(sdata->dev);
+       cfg80211_shutdown_all_interfaces(local->hw.wiphy);
+
+       WARN(local->open_count, "%s: open count remains %d\n",
+            wiphy_name(local->hw.wiphy), local->open_count);
 
        mutex_lock(&local->iflist_mtx);
        list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {