[PATCH] mac80211: fix virtual interface locking
Florian Lohoff noticed a bug in mac80211: when bringing the
master interface down while other virtual interfaces are up
we call dev_close() under a spinlock which is not allowed.
This patch removes the sub_if_lock used by mac80211 in favour
of using an RCU list. All list manipulations are already done
under rtnl so are well protected against each other, and the
read-side locks we took in the RX and TX code are already in
RCU read-side critical sections.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Florian Lohoff <flo@rfc822.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Cc: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 1a43f3e..a5961f1 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -475,9 +475,8 @@
ieee80211_rx_handler *rx_handlers;
ieee80211_tx_handler *tx_handlers;
- rwlock_t sub_if_lock; /* Protects sub_if_list. Cannot be taken under
- * sta_bss_lock or sta_lock. */
- struct list_head sub_if_list;
+ struct list_head interfaces;
+
int sta_scanning;
int scan_channel_idx;
enum { SCAN_SET_CHANNEL, SCAN_SEND_PROBE } scan_state;