net: hns3: fix data race between ring->next_to_clean
authorYunsheng Lin <linyunsheng@huawei.com>
Thu, 25 Apr 2019 12:42:45 +0000 (20:42 +0800)
committerDavid S. Miller <davem@davemloft.net>
Fri, 26 Apr 2019 16:13:28 +0000 (12:13 -0400)
commit26cda2f1613878d9bde11325559f4fca92fff395
tree96d9e8b0e49c895a426e2725d195ed2e4580629f
parent790d23e7c577ed2ef7c49f246ad8d53691fb1b20
net: hns3: fix data race between ring->next_to_clean

hns3_clean_tx_ring calls hns3_nic_reclaim_one_desc to clean
buffers and set ring->next_to_clean, then hns3_nic_net_xmit
reuses the cleaned buffers. But there are no memory barriers
when buffers gets recycled, so the recycled buffers can be
corrupted.

This patch uses smp_store_release to update ring->next_to_clean
and smp_load_acquire to read ring->next_to_clean to properly
hand off buffers from hns3_clean_tx_ring to hns3_nic_net_xmit.

Fixes: 76ad4f0ee747 ("net: hns3: Add support of HNS3 Ethernet Driver for hip08 SoC")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
drivers/net/ethernet/hisilicon/hns3/hns3_enet.h