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net: qcom/emac: specify the correct size when mapping a DMA buffer

PATCH In review Timur Tabi 2 participants 2 messages Sep 22, 2017 – Sep 25, 2017

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Timur Tabi

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#0 lore raw

PATCH 1/1 net: qcom/emac: specify the correct size when mapping a DMA buffer

When mapping the RX DMA buffers, the driver was accidentally specifying zero for the buffer length. Under normal circumstances, SWIOTLB does not need to allocate a bounce buffer, so the address is just mapped without checking the size field. This is why the error was not detected earlier.

Fixes b9b17debc69d ("net: emac: emac gigabit ethernet controller driver")
Cc [email protected]
Signed-off-by Timur Tabi <[email protected]>
---
 drivers/net/ethernet/qualcomm/emac/emac-mac.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
drivers/net/ethernet/qualcomm/emac/emac-mac.c +2 -1
index 0ea3ca09c689..3ed9033e56db 100644
@@ -898,7 +898,8 @@ static void emac_mac_rx_descs_refill(struct emac_adapter *adpt,
 
 		curr_rxbuf->dma_addr =
 			dma_map_single(adpt->netdev->dev.parent, skb->data,
-				       curr_rxbuf->length, DMA_FROM_DEVICE);
+				       adpt->rxbuf_size, DMA_FROM_DEVICE);
+
 		ret = dma_mapping_error(adpt->netdev->dev.parent,
 					curr_rxbuf->dma_addr);
 		if (ret) {
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Code Aurora Forum, a Linux Foundation Collaborative Project.
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#1 lore raw

From: Timur Tabi <[email protected]>
Date: Fri, 22 Sep 2017 15:32:44 -0500

Quoted 8 lines

When mapping the RX DMA buffers, the driver was accidentally specifying zero for the buffer length. Under normal circumstances, SWIOTLB does not need to allocate a bounce buffer, so the address is just mapped without checking the size field. This is why the error was not detected earlier.

Fixes b9b17debc69d ("net: emac: emac gigabit ethernet controller driver")
Cc [email protected]
Signed-off-by Timur Tabi <[email protected]>

Applied and queued up for -stable, thanks.