On Wed, May 27, 2009 at 08:49:56PM +0200, henk wrote: > > I added some extra checks in ath5k/base.c > see http://bugzilla.kernel.org/show_bug.cgi?id=13381#c3 > > This resolves the panic for now. Can you try this patch? It should reduce to a warning if there is still a bug but hopefully you won't see the warning. There's also a chance that it could break beaconing if you kill hostapd and restart it a few times, but I did a little testing and it seemed to work ok. From: Bob Copeland <me@xxxxxxxxxxxxxxx> Date: Thu, 28 May 2009 19:33:50 -0400 Subject: [PATCH] ath5k: disable beacon interrupt when interface is down When we remove the active interface, there's no need to continue sending beacons; doing so would cause a null pointer deref in ieee80211_beacon_get(). Disable the interrupt in remove_interface and add a WARN_ON(!vif) in case there are other instances lurking. Signed-off-by: Bob Copeland <me@xxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/ath5k/base.c | 17 ++++++++++++++++- 1 files changed, 16 insertions(+), 1 deletions(-) diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c index b6fb15e..f011c44 100644 --- a/drivers/net/wireless/ath/ath5k/base.c +++ b/drivers/net/wireless/ath/ath5k/base.c @@ -2070,6 +2070,13 @@ err_unmap: return ret; } +static void ath5k_beacon_disable(struct ath5k_softc *sc) +{ + sc->imask &= ~(AR5K_INT_BMISS | AR5K_INT_SWBA); + ath5k_hw_set_imr(sc->ah, sc->imask); + ath5k_hw_stop_tx_dma(sc->ah, sc->bhalq); +} + /* * Transmit a beacon frame at SWBA. Dynamic updates to the * frame contents are done as needed and the slot time is @@ -2758,6 +2765,7 @@ ath5k_remove_interface(struct ieee80211_hw *hw, ath5k_hw_set_lladdr(sc->ah, mac); sc->vif = NULL; + ath5k_beacon_disable(sc); end: mutex_unlock(&sc->lock); } @@ -3059,7 +3067,14 @@ ath5k_beacon_update(struct ieee80211_hw *hw, struct ieee80211_vif *vif) { int ret; struct ath5k_softc *sc = hw->priv; - struct sk_buff *skb = ieee80211_beacon_get(hw, vif); + struct sk_buff *skb; + + if (WARN_ON(!vif)) { + ret = -EINVAL; + goto out; + } + + skb = ieee80211_beacon_get(hw, vif); if (!skb) { ret = -ENOMEM; -- 1.6.0.6 -- Bob Copeland %% www.bobcopeland.com -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
