From 9bf30ff93dae035bb60ea2f3812e44ac79b31478 Mon Sep 17 00:00:00 2001 From: Sujith Manoharan Date: Fri, 5 Sep 2014 08:03:11 +0530 Subject: [PATCH] ath9k: Fix panic when adding an AP interface If a station interface is already assigned to a context and is active and a second interface of type AP is added, then beaconing on the new interface has to be begin only after the BSS_CHANGED_BEACON_ENABLED flag is sent by mac80211 to the driver. But, since we issue ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL as soon as a new channel context is added, a switch occurs almost immediately before BSS_CHANGED_BEACON_ENABLED is received. When a HW reset is done for the new context, beacons are enabled for the interface since "enable_beacon" in the BSS config maintained in mac80211 is true - but the driver hasn't been notified yet. This causes a panic, since the beacon interval is zero for this interface and ath9k_cmn_beacon_config_ap() doesn't have a safety check. Fix this panic by checking if the beacon params has been cached for this context and use the "enable_beacon" flag maintained locally in the driver. Also, recalculate the summary data after the beacon params have been cached when BSS_CHANGED_BEACON_ENABLED is received. Signed-off-by: Sujith Manoharan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/main.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index 0b3d4d886f0e..2333776d5af0 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -916,8 +916,6 @@ static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data, switch (vif->type) { case NL80211_IFTYPE_AP: iter_data->naps++; - if (vif->bss_conf.enable_beacon) - iter_data->beacons = true; break; case NL80211_IFTYPE_STATION: iter_data->nstations++; @@ -1021,6 +1019,7 @@ void ath9k_calculate_summary_state(struct ath_softc *sc, struct ath_hw *ah = sc->sc_ah; struct ath_common *common = ath9k_hw_common(ah); struct ath9k_vif_iter_data iter_data; + struct ath_beacon_config *cur_conf; ath_chanctx_check_active(sc, ctx); @@ -1037,8 +1036,11 @@ void ath9k_calculate_summary_state(struct ath_softc *sc, ath_hw_setbssidmask(common); if (iter_data.naps > 0) { + cur_conf = &ctx->beacon; ath9k_hw_set_tsfadjust(ah, true); ah->opmode = NL80211_IFTYPE_AP; + if (cur_conf->enable_beacon) + iter_data.beacons = true; } else { ath9k_hw_set_tsfadjust(ah, false); @@ -1695,9 +1697,9 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw, if ((changed & BSS_CHANGED_BEACON_ENABLED) || (changed & BSS_CHANGED_BEACON_INT) || (changed & BSS_CHANGED_BEACON_INFO)) { + ath9k_beacon_config(sc, vif, changed); if (changed & BSS_CHANGED_BEACON_ENABLED) ath9k_calculate_summary_state(sc, avp->chanctx); - ath9k_beacon_config(sc, vif, changed); } if ((avp->chanctx == sc->cur_chan) && -- 2.20.1