[PATCH V2 net] net: hns: Fix the device being used for dma mapping during TX

[PATCH V2 net] net: hns: Fix the device being used for dma mapping during TX

[Salil Mehta]

From: Kejian Yan <yankejian@huawei.com>

This patch fixes the device being used to DMA map skb->data.
Erroneous device assignment causes the crash when SMMU is enabled.
This happens during TX since buffer gets DMA mapped with device
correspondign to net_device and gets unmapped using the device
related to DSAF.

Signed-off-by: Kejian Yan <yankejian@huawei.com>
Reviewed-by: Yisen Zhuang <yisen.zhuang@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
Change log:

PATCH V2: Addressed comment given by,
          Yuan Linyu <linyu.yuan@alcatel-sbell.com.cn>

PATCH V1: Initial submit
---
 drivers/net/ethernet/hisilicon/hns/hns_enet.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/hisilicon/hns/hns_enet.c b/drivers/net/ethernet/hisilicon/hns/hns_enet.c
index 672b646..8aed728 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c
@@ -305,8 +305,8 @@ int hns_nic_net_xmit_hw(struct net_device *ndev,
 			struct hns_nic_ring_data *ring_data)
 {
 	struct hns_nic_priv *priv = netdev_priv(ndev);
-	struct device *dev = priv->dev;
 	struct hnae_ring *ring = ring_data->ring;
+	struct device *dev = ring_to_dev(ring);
 	struct netdev_queue *dev_queue;
 	struct skb_frag_struct *frag;
 	int buf_num;
-- 
1.7.9.5

Re: [PATCH V2 net] net: hns: Fix the device being used for dma mapping during TX

[David Miller]

From: Salil Mehta <salil.mehta@huawei.com>
Date: Thu, 9 Feb 2017 11:46:15 +0000

> From: Kejian Yan <yankejian@huawei.com>
> 
> This patch fixes the device being used to DMA map skb->data.
> Erroneous device assignment causes the crash when SMMU is enabled.
> This happens during TX since buffer gets DMA mapped with device
> correspondign to net_device and gets unmapped using the device
> related to DSAF.
> 
> Signed-off-by: Kejian Yan <yankejian@huawei.com>
> Reviewed-by: Yisen Zhuang <yisen.zhuang@huawei.com>
> Signed-off-by: Salil Mehta <salil.mehta@huawei.com>

Applied, thank you.