Re: [dpdk-dev] [PATCH 2/2] ethdev: fix VLAN offloads set if no relative capabilities

[Wei Hu (Xavier)]

Hi, Andrew Rybchenko


On 2020/6/19 16:37, Andrew Rybchenko wrote:

On 6/19/20 6:42 AM, Wei Hu (Xavier) wrote:

From: Chengchang Tang <tangchengch...@huawei.com>

Currently, there is a potential problem that calling the API function
rte_eth_dev_set_vlan_offload to start a vlan hardware offloads which the
driver does not support. if the PMD driver does not support the relative
hardware offloads and does not check for it, the hardware setting will
not change, but the relative offload in dev->data->dev_conf.rxmode.offloads
will be turned on.

I'm sorry, but I don't understand what 'relative' means in the
context.

Also, please, use 'VLAN' instead of 'vlan' in the description
and log message below.

OK, I will fix it in V2.

It is supposed to check the hardware capabilities to decide whether the
relative callback needs to be called just like the behavior in the API
function named rte_eth_dev_configure.

I think the direction of the fix is right, but it definitely
duplicates checks which are done in some PMDs. I think that it
would be good to do the cleanup in follow up patches.

I will clean them in V2.

Fixes: 81f9db8ecc2c ("ethdev: add vlan offload support")

Most likely it is incorrect, since generic Rx offloads were
introduced later.

OK, I will replace it with the following statement in V2.

  Fixes: a4996bd89c42 ("ethdev: new Rx/Tx offloads API")

Thanks, Xavier

Cc: sta...@dpdk.org

Signed-off-by: Chengchang Tang <tangchengch...@huawei.com>
Signed-off-by: Wei Hu (Xavier) <xavier.hu...@huawei.com>
---
  lib/librte_ethdev/rte_ethdev.c | 21 +++++++++++++++++++++
  1 file changed, 21 insertions(+)

diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
index 122fd2a..5176a0e 100644
--- a/lib/librte_ethdev/rte_ethdev.c
+++ b/lib/librte_ethdev/rte_ethdev.c
@@ -3261,12 +3261,14 @@ rte_eth_dev_set_vlan_ether_type(uint16_t port_id,
  int
  rte_eth_dev_set_vlan_offload(uint16_t port_id, int offload_mask)
  {
+       struct rte_eth_dev_info dev_info;
        struct rte_eth_dev *dev;
        int ret = 0;
        int mask = 0;
        int cur, org = 0;
        uint64_t orig_offloads;
        uint64_t dev_offloads;
+       uint64_t new_offloads;

RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);

        dev = &rte_eth_devices[port_id];
@@ -3320,6 +3322,25 @@ rte_eth_dev_set_vlan_offload(uint16_t port_id, int 
offload_mask)
        if (mask == 0)
                return ret;

+ ret = rte_eth_dev_info_get(port_id, &dev_info);

+       if (ret != 0)
+               return ret;
+
+       /*
+        * New added Rx vlan offloading which are not enabled in
+        * rte_eth_dev_configure() must be within its device capabilities
+        */
+       if ((dev_offloads & dev_info.rx_offload_capa) != dev_offloads) {
+               new_offloads = dev_offloads & ~orig_offloads;
+               RTE_ETHDEV_LOG(ERR,
+                       "Ethdev port_id=%u requested new added vlan offloads "
+                       "0x%" PRIx64 " must be within Rx offloads capabilities "
+                       "0x%"PRIx64 " in %s()\n",
+                       port_id, new_offloads, dev_info.rx_offload_capa,
+                       __func__);
+               return -EINVAL;
+       }
+
        RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->vlan_offload_set, -ENOTSUP);
        dev->data->dev_conf.rxmode.offloads = dev_offloads;
        ret = (*dev->dev_ops->vlan_offload_set)(dev, mask);