Commit 2fa4cb90 authored Jan 28, 2014 by Stanislaw Gruszka Committed by John W. Linville Feb 04, 2014

ath9k_htc: make ->sta_rc_update atomic for most calls

sta_rc_update() callback must be atomic, hence we can not take mutexes
or do other operations, which can sleep in ath9k_htc_sta_rc_update().

I think we can just return from ath9k_htc_sta_rc_update(), if it is
called without IEEE80211_RC_SUPP_RATES_CHANGED bit. That will help
with scheduling while atomic bug for most cases (except mesh and IBSS
modes).

For mesh and IBSS I do not see other solution like creating additional
workqueue, because sending firmware command require us to sleep, but
this can be done in additional patch.

Patch partially fixes bug:
https://bugzilla.redhat.com/show_bug.cgi?id=990955



Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent 235c0dc5

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

+13 −12

Original line number	Diff line number	Diff line
		@@ -1315,10 +1315,12 @@ static void ath9k_htc_sta_rc_update(struct ieee80211_hw *hw,
		struct ath_common *common = ath9k_hw_common(priv->ah);
		struct ath9k_htc_target_rate trate;

		if (!(changed & IEEE80211_RC_SUPP_RATES_CHANGED))
		return;

		mutex_lock(&priv->mutex);
		ath9k_htc_ps_wakeup(priv);

		if (changed & IEEE80211_RC_SUPP_RATES_CHANGED) {
		memset(&trate, 0, sizeof(struct ath9k_htc_target_rate));
		ath9k_htc_setup_rate(priv, sta, &trate);
		if (!ath9k_htc_send_rate_cmd(priv, &trate))
		@@ -1329,7 +1331,6 @@ static void ath9k_htc_sta_rc_update(struct ieee80211_hw *hw,
		ath_dbg(common, CONFIG,
		"Unable to update supported rates for sta: %pM\n",
		sta->addr);
		}

		ath9k_htc_ps_restore(priv);
		mutex_unlock(&priv->mutex);