From 723955913e77fec6659be7531458997df6748d5c Mon Sep 17 00:00:00 2001 From: Aleksander Jan Bajkowski Date: Tue, 28 Dec 2021 22:49:10 +0100 Subject: [PATCH] net: lantiq_etop: add missing comment for wmb() This patch adds the missing code comment for memory barrier call and fixes checkpatch warning: WARNING: memory barrier without comment + wmb(); Signed-off-by: Aleksander Jan Bajkowski Link: https://lore.kernel.org/r/20211228214910.70810-1-olek2@wp.pl Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/lantiq_etop.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/ethernet/lantiq_etop.c b/drivers/net/ethernet/lantiq_etop.c index 14059e11710a..6f049278c083 100644 --- a/drivers/net/ethernet/lantiq_etop.c +++ b/drivers/net/ethernet/lantiq_etop.c @@ -498,6 +498,7 @@ ltq_etop_tx(struct sk_buff *skb, struct net_device *dev) spin_lock_irqsave(&priv->lock, flags); desc->addr = ((unsigned int) dma_map_single(&priv->pdev->dev, skb->data, len, DMA_TO_DEVICE)) - byte_offset; + /* Make sure the address is written before we give it to HW */ wmb(); desc->ctl = LTQ_DMA_OWN | LTQ_DMA_SOP | LTQ_DMA_EOP | LTQ_DMA_TX_OFFSET(byte_offset) | (len & LTQ_DMA_SIZE_MASK); -- 2.20.1