mac80211 must not enable aggregation wile transmitting a fragmented
MPDU. Enforce that for mac80211 internal TX queues (iTXQs).
Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/oe-lkp/[email protected]
Signed-off-by: Alexander Wetzel <[email protected]>
---
This bug was exposed by lkp-tests after switching hwsim to iTXQ.
I had some problems reproducing the issue first and had to use the
kernel config from lkp-tests to reproduce the race.
This patch assumes that
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/
has been applied, too.
It's fixing a similar race and the logic overlaps.
Alexander
---
net/mac80211/agg-tx.c | 2 --
net/mac80211/ht.c | 31 +++++++++++++++++++++++++++++++
net/mac80211/tx.c | 18 ++++++------------
3 files changed, 37 insertions(+), 14 deletions(-)
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 9c40f8d3bce8..3426d770bef8 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -511,8 +511,6 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
*/
clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
- ieee80211_agg_stop_txq(sta, tid);
-
/*
* Make sure no packets are being processed. This ensures that
* we have a valid starting sequence number and that in-flight
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index 83bc41346ae7..5315ab750280 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -391,6 +391,37 @@ void ieee80211_ba_session_work(struct work_struct *work)
tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
if (!blocked && tid_tx) {
+ struct txq_info *txqi = to_txq_info(sta->sta.txq[tid]);
+ struct ieee80211_sub_if_data *sdata =
+ vif_to_sdata(txqi->txq.vif);
+ struct fq *fq = &sdata->local->fq;
+
+ spin_lock_bh(&fq->lock);
+
+ /* Allow only frags to be dequeued */
+ set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
+
+ if (!skb_queue_empty(&txqi->frags)) {
+ /* Fragmented Tx is ongoing, wait for it to
+ * finish. Reschedule worker to retry later.
+ */
+
+ spin_unlock_bh(&fq->lock);
+ spin_unlock_bh(&sta->lock);
+
+ /* Give the task working on the txq a chance
+ * to send out the queued frags
+ */
+ synchronize_net();
+
+ mutex_unlock(&sta->ampdu_mlme.mtx);
+
+ ieee80211_queue_work(&sdata->local->hw, work);
+ return;
+ }
+
+ spin_unlock_bh(&fq->lock);
+
/*
* Assign it over to the normal tid_tx array
* where it "goes live".
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 178043f84489..defe97a31724 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1129,7 +1129,6 @@ static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
struct sk_buff *purge_skb = NULL;
if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
- info->flags |= IEEE80211_TX_CTL_AMPDU;
reset_agg_timer = true;
} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
/*
@@ -1161,7 +1160,6 @@ static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
if (!tid_tx) {
/* do nothing, let packet pass through */
} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
- info->flags |= IEEE80211_TX_CTL_AMPDU;
reset_agg_timer = true;
} else {
queued = true;
@@ -3677,8 +3675,7 @@ static void __ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata,
info->band = fast_tx->band;
info->control.vif = &sdata->vif;
info->flags = IEEE80211_TX_CTL_FIRST_FRAGMENT |
- IEEE80211_TX_CTL_DONTFRAG |
- (ampdu ? IEEE80211_TX_CTL_AMPDU : 0);
+ IEEE80211_TX_CTL_DONTFRAG;
info->control.flags = IEEE80211_TX_CTRL_FAST_XMIT |
u32_encode_bits(IEEE80211_LINK_UNSPECIFIED,
IEEE80211_TX_CTRL_MLO_LINK);
@@ -3804,9 +3801,6 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
spin_lock_bh(&fq->lock);
- if (unlikely(test_bit(IEEE80211_TXQ_STOP, &txqi->flags)))
- goto out;
-
/* Make sure fragments stay together. */
skb = __skb_dequeue(&txqi->frags);
if (unlikely(skb)) {
@@ -3816,6 +3810,9 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
IEEE80211_SKB_CB(skb)->control.flags &=
~IEEE80211_TX_INTCFL_NEED_TXPROCESSING;
} else {
+ if (unlikely(test_bit(IEEE80211_TXQ_STOP, &txqi->flags)))
+ goto out;
+
skb = fq_tin_dequeue(fq, tin, fq_tin_dequeue_func);
}
@@ -3866,9 +3863,8 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
}
if (test_bit(IEEE80211_TXQ_AMPDU, &txqi->flags))
- info->flags |= IEEE80211_TX_CTL_AMPDU;
- else
- info->flags &= ~IEEE80211_TX_CTL_AMPDU;
+ info->flags |= (IEEE80211_TX_CTL_AMPDU |
+ IEEE80211_TX_CTL_DONTFRAG);
if (info->flags & IEEE80211_TX_CTL_HW_80211_ENCAP) {
if (!ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
@@ -4602,8 +4598,6 @@ static void ieee80211_8023_xmit(struct ieee80211_sub_if_data *sdata,
info = IEEE80211_SKB_CB(skb);
memset(info, 0, sizeof(*info));
- if (tid_tx)
- info->flags |= IEEE80211_TX_CTL_AMPDU;
info->hw_queue = sdata->vif.hw_queue[queue];
--
2.39.0