On Fri, May 4, 2012 at 12:10 PM, Mohammed Shafi <shafi.wireless@xxxxxxxxx> wrote: > Hi Larry, > > On Fri, May 4, 2012 at 11:47 AM, Larry Finger <Larry.Finger@xxxxxxxxxxxx> wrote: >> On 05/03/2012 01:38 PM, Johannes Berg wrote: >>> >>> diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c >>> index 5b7053c..40d3ff4 100644 >>> --- a/net/mac80211/agg-tx.c >>> +++ b/net/mac80211/agg-tx.c >>> @@ -421,16 +421,22 @@ static void >>> sta_tx_agg_session_timer_expired(unsigned long data) >>> struct tid_ampdu_tx *tid_tx; >>> unsigned long timeout; >>> >>> - tid_tx = rcu_dereference_protected_tid_tx(sta, *ptid); >>> - if (!tid_tx) >>> + rcu_read_lock(); >>> + tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[*ptid]); Larry, Johannes seems to use rcu_dereference straight way just like in 'sta_addba_resp_timer_expired' and have it protected by rcu_read_locks >>> + if (!tid_tx) { >>> + rcu_read_unlock(); >>> return; >>> + } >>> >>> timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); >>> if (time_is_after_jiffies(timeout)) { >>> mod_timer(&tid_tx->session_timer, timeout); >>> + rcu_read_unlock(); >>> return; >>> } >>> >>> + rcu_read_unlock(); >>> + >>> #ifdef CONFIG_MAC80211_HT_DEBUG >>> printk(KERN_DEBUG "tx session timer expired on tid %d\n", >>> (u16)*ptid); >>> #endif >> >> >> This patch is the same as was proposed by Mohammed on May 1. I must have >> messed up the testing as I thought it failed; however, it is now working. > > honestly i am not sure about the technical details, but Johannes patch > seems to follow almost similar > what's is done in 'sta_addba_resp_timer_expired'. while thought that > is being also with mutex under hold > but the difference is the lock is unhold before > ieee80211_stop_tx_ba_session is called. > >> >> Mohammed - I plan on submitting this to John with a "From:" from you along >> with your s-o-b. Is that OK. It will be submitted for inclusion in 3.5. >> >> Larry >> > > > -- > thanks, > shafi -- thanks, shafi -- 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