ath9k: fix panic while cleaning up virtaul wifis

num_sec_wiphy means max secondary wifis that the driver can accomudate.
So cancelling wiphy work should be based on the presence of
secondary wifis.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/init.c

@@ -787,12 +787,12 @@ void ath9k_deinit_device(struct ath_softc *sc)
 		ieee80211_unregister_hw(aphy->hw);
 		ieee80211_free_hw(aphy->hw);
 	}
-	kfree(sc->sec_wiphy);
 
 	ieee80211_unregister_hw(hw);
 	ath_rx_cleanup(sc);
 	ath_tx_cleanup(sc);
 	ath9k_deinit_softc(sc);
+	kfree(sc->sec_wiphy);
 }
 
 void ath_descdma_cleanup(struct ath_softc *sc,

drivers/net/wireless/ath/ath9k/main.c

@@ -1269,6 +1269,7 @@ static void ath9k_stop(struct ieee80211_hw *hw)
 	struct ath_softc *sc = aphy->sc;
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
+	int i;
 
 	mutex_lock(&sc->mutex);
 
@@ -1281,7 +1282,12 @@ static void ath9k_stop(struct ieee80211_hw *hw)
 	cancel_work_sync(&sc->paprd_work);
 	cancel_work_sync(&sc->hw_check_work);
 
-	if (!sc->num_sec_wiphy) {
+	for (i = 0; i < sc->num_sec_wiphy; i++) {
+		if (sc->sec_wiphy[i])
+			break;
+	}
+
+	if (i == sc->num_sec_wiphy) {
 		cancel_delayed_work_sync(&sc->wiphy_work);
 		cancel_work_sync(&sc->chan_work);
 	}