[dpdk-dev] [PATCH] 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....@intel.com>
---
 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..042edadd9 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, temp_err;
+
+       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.
+                */
+               temp_err = iavf_add_del_mc_addr_list(adapter, vf->mc_addrs,
+                                                    vf->mc_addrs_num, true);
+               if (temp_err)
+                       return temp_err;
+       } 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;
-- 
2.13.6