# \[PATCH net 1/2\] net: macb: credit unsent frames to BQL in macb\_tx\_error\_task() - From: Nicolai Buchwitz \ - Date: 2026-11-07 20:59:37 - List: netdev - Page: https://ratatoskr.run/netdev/2026/11/17890849 - Thread: https://ratatoskr.run/netdev/2026/11/17890847/t.md ```text The frames dropped on a TX error are never returned to BQL. Each error shrinks the BQL budget for good until the queue stops with an empty ring. netdev_tx_reset_queue() is not safe here as the task runs without tx_ptr_lock, so macb_start_xmit() may still be queueing. Fixes: e6a532185daa ("net: cadence: macb: Implement BQL") Signed-off-by: Nicolai Buchwitz --- drivers/net/ethernet/cadence/macb_main.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index f087f278f9e56..b6105f915fe35 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -1412,10 +1412,8 @@ static void macb_tx_error_task(struct work_struct *work) skb->data); bp->netdev->stats.tx_packets++; queue->stats.tx_packets++; - packets++; bp->netdev->stats.tx_bytes += skb->len - tx_skb->fcs_len; queue->stats.tx_bytes += skb->len - tx_skb->fcs_len; - bytes += skb->len; } } else { /* "Buffers exhausted mid-frame" errors may only happen @@ -1428,6 +1426,12 @@ static void macb_tx_error_task(struct work_struct *work) desc->ctrl = ctrl | MACB_BIT(TX_USED); } + /* BQL has to see every frame leaving the ring, sent or not */ + if (skb) { + packets++; + bytes += skb->len; + } + macb_tx_unmap(&bp->info, tx_skb, 0); } -- 2.53.0 ```