mac80211: temporarily disable reorder release timer

Several serve threading problems in the current
release reorder timer implementation have been
discovered.

A lengthy discussion - which lists some of the
pitfalls and possible solutions - can be found at:
 http://marc.info/?t=128635927000001

But due to the complicated nature of the subject and
the imminent advent of a new -rc cycle, it was
decided to disable the feature for the time being.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Christian Lamparter 2010-10-08 22:35:09 +02:00 committed by John W. Linville
parent d12c74528e
commit 15943a72c7
1 changed files with 24 additions and 0 deletions

View File

@ -622,6 +622,26 @@ static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
tid_agg_rx->buf_size;
}
/*
* Disable the reorder release timer for now.
*
* The current implementation lacks a proper locking scheme
* which would protect vital statistic and debug counters
* from being updated by two different but concurrent BHs.
*
* More information about the topic is available from:
* - thread: http://marc.info/?t=128635927000001
*
* What was wrong:
* => http://marc.info/?l=linux-wireless&m=128636170811964
* "Basically the thing is that until your patch, the data
* in the struct didn't actually need locking because it
* was accessed by the RX path only which is not concurrent."
*
* List of what needs to be fixed:
* => http://marc.info/?l=linux-wireless&m=128656352920957
*
if (tid_agg_rx->stored_mpdu_num) {
j = index = seq_sub(tid_agg_rx->head_seq_num,
tid_agg_rx->ssn) % tid_agg_rx->buf_size;
@ -640,6 +660,10 @@ static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
} else {
del_timer(&tid_agg_rx->reorder_timer);
}
*/
set_release_timer:
return;
}
/*