[PATCH AUTOSEL for 4.14 023/100] net: mvpp2: allocate zeroed tx descriptors

From: Sasha Levin
Date: Sun Jan 28 2018 - 18:12:50 EST


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@xxxxxxxxxxxxx>
---
drivers/net/ethernet/marvell/mvpp2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index fcf9ba5eb8d1..e9bc551d7621 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c
@@ -5408,7 +5408,7 @@ static int mvpp2_aggr_txq_init(struct platform_device *pdev,
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)
--
2.11.0