Re: 2.6.32-rc4-git1 -- INFO: possible circular locking dependency detected

[Johannes Berg]

Actually ... seems to be easy to fix.

Can you reproduce this reliably? I suspect not. If you can, try the
patch below to make sure -- I'm pretty certain it is a correct patch
anyhow though.

johannes

---
 net/mac80211/agg-tx.c |   12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

--- wireless-testing.orig/net/mac80211/agg-tx.c	2009-10-16 19:13:48.000000000 +0900
+++ wireless-testing/net/mac80211/agg-tx.c	2009-10-16 19:15:12.000000000 +0900
@@ -666,11 +666,13 @@ void ieee80211_process_addba_resp(struct
 
 	state = &sta->ampdu_mlme.tid_state_tx[tid];
 
+	del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
+
 	spin_lock_bh(&sta->lock);
 
 	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 		spin_unlock_bh(&sta->lock);
-		return;
+		goto timer_still_needed;
 	}
 
 	if (mgmt->u.action.u.addba_resp.dialog_token !=
@@ -679,13 +681,13 @@ void ieee80211_process_addba_resp(struct
 #ifdef CONFIG_MAC80211_HT_DEBUG
 		printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
 #endif /* CONFIG_MAC80211_HT_DEBUG */
-		return;
+		goto timer_still_needed;
 	}
 
-	del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 #ifdef CONFIG_MAC80211_HT_DEBUG
 	printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
 #endif /* CONFIG_MAC80211_HT_DEBUG */
+
 	if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
 			== WLAN_STATUS_SUCCESS) {
 		u8 curstate = *state;
@@ -700,4 +702,8 @@ void ieee80211_process_addba_resp(struct
 		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
 	}
 	spin_unlock_bh(&sta->lock);
+
+	return;
+ timer_still_needed:
+	add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 }


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