[PATCH 4.14 081/159] net: mvpp2: allocate zeroed tx descriptors

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yan Markman <ymarkman@xxxxxxxxxxx>


[ Upstream commit a154f8e399a063137fc42b961f437248d55ece29 ]

Reserved and unused fields in the Tx descriptors should be 0. The PPv2
driver doesn't clear them at run-time (for performance reasons) but
these descriptors aren't zeroed when allocated, which can lead to
unpredictable behaviors. This patch fixes this by using
dma_zalloc_coherent instead of dma_alloc_coherent.

Fixes: 3f518509dedc ("ethernet: Add new driver for Marvell Armada 375 network unit")
Signed-off-by: Yan Markman <ymarkman@xxxxxxxxxxx>
[Antoine: commit message]
Signed-off-by: Antoine Tenart <antoine.tenart@xxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>

Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
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
@@ -5399,7 +5399,7 @@ static int mvpp2_aggr_txq_init(struct pl
 	u32 txq_dma;
 
 	/* Allocate memory for TX descriptors */
-	aggr_txq->descs = dma_alloc_coherent(&pdev->dev,
+	aggr_txq->descs = dma_zalloc_coherent(&pdev->dev,
 				MVPP2_AGGR_TXQ_SIZE * MVPP2_DESC_ALIGNED_SIZE,
 				&aggr_txq->descs_dma, GFP_KERNEL);
 	if (!aggr_txq->descs)