[dpdk-dev] [PATCH v2] net/iavf: fix adding multicast MAC address

[Guinan Sun]

When the multicast address is added, it will flush
previous addresses first, and then add new ones.
So when adding an address that exceeds the upper limit
causes a failure, you need to add the previous address
list back. This patch fixes the issue.

Fixes: 05e4c3aff35f ("net/iavf: support multicast configuration")

Signed-off-by: Guinan Sun <guinanx.sun at intel.com>
Tested-by: Peng Yuan <yuan.peng at intel.com>
---
v2:
* modify the variable name
---
 drivers/net/iavf/iavf_ethdev.c | 30 ++++++++++++++++++++++--------
 drivers/net/iavf/iavf_vchnl.c  |  3 ---
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/drivers/net/iavf/iavf_ethdev.c b/drivers/net/iavf/iavf_ethdev.c
index e68e3bc71..596cf24cf 100644
--- a/drivers/net/iavf/iavf_ethdev.c
+++ b/drivers/net/iavf/iavf_ethdev.c
@@ -164,7 +164,14 @@ iavf_set_mc_addr_list(struct rte_eth_dev *dev,
 	struct iavf_info *vf = IAVF_DEV_PRIVATE_TO_VF(dev->data->dev_private);
 	struct iavf_adapter *adapter =
 		IAVF_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private);
-	int err;
+	int err, ret;
+
+	if (mc_addrs_num > IAVF_NUM_MACADDR_MAX) {
+		PMD_DRV_LOG(ERR,
+			    "can't add more than a limited number (%u) of addresses.",
+			    (uint32_t)IAVF_NUM_MACADDR_MAX);
+		return -EINVAL;
+	}
 
 	/* flush previous addresses */
 	err = iavf_add_del_mc_addr_list(adapter, vf->mc_addrs, vf->mc_addrs_num,
@@ -172,17 +179,24 @@ iavf_set_mc_addr_list(struct rte_eth_dev *dev,
 	if (err)
 		return err;
 
-	vf->mc_addrs_num = 0;
-
 	/* add new ones */
 	err = iavf_add_del_mc_addr_list(adapter, mc_addrs, mc_addrs_num, true);
-	if (err)
-		return err;
 
-	vf->mc_addrs_num = mc_addrs_num;
-	memcpy(vf->mc_addrs, mc_addrs, mc_addrs_num * sizeof(*mc_addrs));
+	if (err) {
+		/* When adding new addresses fail, need to add the
+		 * previous addresses back.
+		 */
+		ret = iavf_add_del_mc_addr_list(adapter, vf->mc_addrs,
+						vf->mc_addrs_num, true);
+		if (ret)
+			return ret;
+	} else {
+		vf->mc_addrs_num = mc_addrs_num;
+		memcpy(vf->mc_addrs,
+		       mc_addrs, mc_addrs_num * sizeof(*mc_addrs));
+	}
 
-	return 0;
+	return err;
 }
 
 static int
diff --git a/drivers/net/iavf/iavf_vchnl.c b/drivers/net/iavf/iavf_vchnl.c
index db0b76876..a2295f879 100644
--- a/drivers/net/iavf/iavf_vchnl.c
+++ b/drivers/net/iavf/iavf_vchnl.c
@@ -1107,9 +1107,6 @@ iavf_add_del_mc_addr_list(struct iavf_adapter *adapter,
 	if (mc_addrs == NULL || mc_addrs_num == 0)
 		return 0;
 
-	if (mc_addrs_num > IAVF_NUM_MACADDR_MAX)
-		return -EINVAL;
-
 	list = (struct virtchnl_ether_addr_list *)cmd_buffer;
 	list->vsi_id = vf->vsi_res->vsi_id;
 	list->num_elements = mc_addrs_num;
-- 
2.17.1