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net: mvpp2: fix DMA address calculation in mvpp2_txq_inc_put() 

When TX descriptors are filled in, the buffer DMA address is split
between the tx_desc->buf_phys_addr field (high-order bits) and
tx_desc->packet_offset field (5 low-order bits).

However, when we re-calculate the DMA address from the TX descriptor in
mvpp2_txq_inc_put(), we do not take tx_desc->packet_offset into
account. This means that when the DMA address is not aligned on a 32
bytes boundary, we end up calling dma_unmap_single() with a DMA address
that was not the one returned by dma_map_single().

This inconsistency is detected by the kernel when DMA_API_DEBUG is
enabled. We fix this problem by properly calculating the DMA address in
mvpp2_txq_inc_put().

Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thomas Petazzoni 2017-02-21 11:28:01 +01:00 committed by David S. Miller
parent b3bdc3acbb
commit 239a3b6636
1 changed files with 1 additions and 1 deletions
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2
drivers/net/ethernet/marvell/mvpp2.c
View File

@ -991,7 +991,7 @@ static void mvpp2_txq_inc_put(struct mvpp2_txq_pcpu *txq_pcpu,
txq_pcpu->buffs + txq_pcpu->txq_put_index;
tx_buf->skb = skb;
tx_buf->size = tx_desc->data_size;
tx_buf->phys = tx_desc->buf_phys_addr;
tx_buf->phys = tx_desc->buf_phys_addr + tx_desc->packet_offset;
txq_pcpu->txq_put_index++;
if (txq_pcpu->txq_put_index == txq_pcpu->size)
txq_pcpu->txq_put_index = 0;