This is a note to let you know that I've just added the patch titled net: mvpp2: fix DMA address calculation in mvpp2_txq_inc_put() to the 4.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-mvpp2-fix-dma-address-calculation-in-mvpp2_txq_inc_put.patch and it can be found in the queue-4.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 239a3b663647869330955ec59caac0100ef9b60a Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> Date: Tue, 21 Feb 2017 11:28:01 +0100 Subject: net: mvpp2: fix DMA address calculation in mvpp2_txq_inc_put() From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> commit 239a3b663647869330955ec59caac0100ef9b60a upstream. 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(). Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/marvell/mvpp2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ethernet/marvell/mvpp2.c +++ b/drivers/net/ethernet/marvell/mvpp2.c @@ -991,7 +991,7 @@ static void mvpp2_txq_inc_put(struct mvp 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; Patches currently in stable-queue which might be from thomas.petazzoni@xxxxxxxxxxxxxxxxxx are queue-4.10/net-mvpp2-fix-dma-address-calculation-in-mvpp2_txq_inc_put.patch