diff options
author | Yunsheng Lin <linyunsheng@huawei.com> | 2019-04-25 20:42:45 +0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2019-04-26 12:13:28 -0400 |
commit | 26cda2f1613878d9bde11325559f4fca92fff395 (patch) | |
tree | 96d9e8b0e49c895a426e2725d195ed2e4580629f /drivers/net/ethernet/hisilicon/hns3/hns3_enet.h | |
parent | 790d23e7c577ed2ef7c49f246ad8d53691fb1b20 (diff) |
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>
Diffstat (limited to 'drivers/net/ethernet/hisilicon/hns3/hns3_enet.h')
-rw-r--r-- | drivers/net/ethernet/hisilicon/hns3/hns3_enet.h | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h index cec56a505e85..2b4f5ea3fddf 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h @@ -581,8 +581,11 @@ union l4_hdr_info { static inline int ring_space(struct hns3_enet_ring *ring) { - int begin = ring->next_to_clean; - int end = ring->next_to_use; + /* This smp_load_acquire() pairs with smp_store_release() in + * hns3_nic_reclaim_one_desc called by hns3_clean_tx_ring. + */ + int begin = smp_load_acquire(&ring->next_to_clean); + int end = READ_ONCE(ring->next_to_use); return ((end >= begin) ? (ring->desc_num - end + begin) : (begin - end)) - 1; |