From daf158d0d544cec80b7b30deff8cfc59a6e17610 Mon Sep 17 00:00:00 2001 From: Simon Guinot Date: Tue, 15 Sep 2015 22:41:21 +0200 Subject: [PATCH] net: mvneta: fix DMA buffer unmapping in mvneta_rx() This patch fixes a regression introduced by the commit a84e32894191 ("net: mvneta: fix refilling for Rx DMA buffers"). Due to this commit the newly allocated Rx buffers are DMA-unmapped in place of those passed to the networking stack. Obviously, this causes data corruptions. This patch fixes the issue by ensuring that the right Rx buffers are DMA-unmapped. Reported-by: Oren Laskin Signed-off-by: Simon Guinot Fixes: a84e32894191 ("net: mvneta: fix refilling for Rx DMA buffers") Cc: # v3.8+ Tested-by: Oren Laskin Signed-off-by: David S. Miller --- drivers/net/ethernet/marvell/mvneta.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index fe2299ac4f5c..09ec32e33076 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -1479,6 +1479,7 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo, struct mvneta_rx_desc *rx_desc = mvneta_rxq_next_desc_get(rxq); struct sk_buff *skb; unsigned char *data; + dma_addr_t phys_addr; u32 rx_status; int rx_bytes, err; @@ -1486,6 +1487,7 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo, rx_status = rx_desc->status; rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); data = (unsigned char *)rx_desc->buf_cookie; + phys_addr = rx_desc->buf_phys_addr; if (!mvneta_rxq_desc_is_first_last(rx_status) || (rx_status & MVNETA_RXD_ERR_SUMMARY)) { @@ -1534,7 +1536,7 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo, if (!skb) goto err_drop_frame; - dma_unmap_single(dev->dev.parent, rx_desc->buf_phys_addr, + dma_unmap_single(dev->dev.parent, phys_addr, MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE); rcvd_pkts++; -- 2.34.1