From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> [ Upstream commit 36fb7435b6ac4d288a2d4deea8934f9456ab46b6 ] The mvpp2_txq_bufs_free() function is called upon TX completion to DMA unmap TX buffers, and free the corresponding SKBs. It gets the references to the SKB to free and the DMA buffer to unmap from a per-CPU txq_pcpu data structure. However, the code currently increments the pointer to the next entry before doing the DMA unmap and freeing the SKB. It does not cause any visible problem because for a given SKB the TX completion is guaranteed to take place on the CPU where the TX was started. However, it is much more logical to increment the pointer to the next entry once the current entry has been completely unmapped/released. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> Acked-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> --- drivers/net/ethernet/marvell/mvpp2.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c index 0a4e81a253fb..ed6fae964ec5 100644 --- a/drivers/net/ethernet/marvell/mvpp2.c +++ b/drivers/net/ethernet/marvell/mvpp2.c @@ -4413,13 +4413,12 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port, struct mvpp2_txq_pcpu_buf *tx_buf = txq_pcpu->buffs + txq_pcpu->txq_get_index; - mvpp2_txq_inc_get(txq_pcpu); - dma_unmap_single(port->dev->dev.parent, tx_buf->phys, tx_buf->size, DMA_TO_DEVICE); - if (!tx_buf->skb) - continue; - dev_kfree_skb_any(tx_buf->skb); + if (tx_buf->skb) + dev_kfree_skb_any(tx_buf->skb); + + mvpp2_txq_inc_get(txq_pcpu); } } -- 2.11.0