[PATCH] net/iavf: fix VLAN offload when inner VLAN is not supported

[Mandal, Anurag]

> -----Original Message-----
> From: Mandal, Anurag <anurag.mandal at intel.com>
> Sent: 16 July 2026 04:23
> To: dev at dpdk.org
> Cc: Richardson, Bruce <bruce.richardson at intel.com>; Medvedkin, Vladimir
> <vladimir.medvedkin at intel.com>; Mandal, Anurag
> <anurag.mandal at intel.com>; stable at dpdk.org
> Subject: [PATCH] net/iavf: fix VLAN offload when inner VLAN is not supported
> 
> In Double VLAN mode (DVM) i.e. when RTE_ETH_RX_OFFLOAD_VLAN_EXTEND
> is enabled, the single VLAN offloads are programmed on the inner VLAN
> (0x8100) engine by iavf_config_vlan_strip_v2() & iavf_config_vlan_insert_v2().
> When the PF/hardware does not advertise inner VLAN offloading capabilities,
> these functions return -ENOTSUP.
> 
> On the enable path,these -ENOTSUP are trsnalated into -EIO, which makes
> device configuration fail.
> However, in DVM, with the default outer TPID set as 0x8100, a single 0x8100
> tagged VLAN frame is handled by the outer VLAN engine, so the missing inner
> capability is harmless and should not fail the configuration.
> 
> This patch fixes the same by returning success when DVM is enabled and the
> outer TPID is 0x8100, so the outer VLAN engine services the single VLAN.
> Changed "qinq" flag from 'int' to 'bool' to address memory wastage.
> 
> Fixes: 8599d7604e0a ("net/iavf: support QinQ strip")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Anurag Mandal <anurag.mandal at intel.com>
Tested-by: Daxue Gao <daxuex.gao at intel.com>

> ---
>  drivers/net/intel/iavf/iavf_vchnl.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/intel/iavf/iavf_vchnl.c
> b/drivers/net/intel/iavf/iavf_vchnl.c
> index f8fffa7802..f346837bf1 100644
> --- a/drivers/net/intel/iavf/iavf_vchnl.c
> +++ b/drivers/net/intel/iavf/iavf_vchnl.c
> @@ -920,7 +920,7 @@ iavf_config_vlan_strip_v2(struct iavf_adapter *adapter,
> bool enable)
>  	uint8_t msg_buf[IAVF_AQ_BUF_SZ] = {0};
>  	struct iavf_cmd_info args;
>  	uint32_t *ethertype;
> -	int qinq = adapter->dev_data->dev_conf.rxmode.offloads &
> +	bool qinq = adapter->dev_data->dev_conf.rxmode.offloads &
>  		   RTE_ETH_RX_OFFLOAD_VLAN_EXTEND;
>  	bool strip_qinq = adapter->dev_data->dev_conf.rxmode.offloads &
>  			  RTE_ETH_RX_OFFLOAD_QINQ_STRIP;
> @@ -943,7 +943,8 @@ iavf_config_vlan_strip_v2(struct iavf_adapter *adapter,
> bool enable)
>  		 (stripping_caps->inner & VIRTCHNL_VLAN_TOGGLE))
>  		ethertype = &vlan_strip.inner_ethertype_setting;
>  	else
> -		return -ENOTSUP;
> +		/* Return success for non-inner VLAN supported hardware */
> +		return (qinq && adapter->tpid == RTE_ETHER_TYPE_VLAN) ? 0
> : -ENOTSUP;
> 
>  	memset(&vlan_strip, 0, sizeof(vlan_strip));
>  	vlan_strip.vport_id = vf->vsi_res->vsi_id; @@ -1036,7 +1037,8 @@
> iavf_config_vlan_insert_v2(struct iavf_adapter *adapter, bool enable)
>  		 (insertion_caps->inner & VIRTCHNL_VLAN_TOGGLE))
>  		ethertype = &vlan_insert.inner_ethertype_setting;
>  	else
> -		return -ENOTSUP;
> +		/* Return success for non-inner VLAN supported hardware */
> +		return (qinq && adapter->tpid == RTE_ETHER_TYPE_VLAN) ? 0
> : -ENOTSUP;
> 
>  	memset(&vlan_insert, 0, sizeof(vlan_insert));
>  	vlan_insert.vport_id = vf->vsi_res->vsi_id; @@ -1067,7 +1069,7 @@
> iavf_add_del_vlan_v2(struct iavf_adapter *adapter, uint16_t vlanid, bool add)
>  	struct virtchnl_vlan *vlan_setting;
>  	struct iavf_cmd_info args;
>  	uint32_t filtering_caps;
> -	int qinq = adapter->dev_data->dev_conf.rxmode.offloads &
> +	bool qinq = adapter->dev_data->dev_conf.rxmode.offloads &
>  		   RTE_ETH_RX_OFFLOAD_VLAN_EXTEND;
>  	int err;
> 
> --
> 2.43.0