Re: [PATCH v2] net: stmmac: skip VLAN restore when VLAN hash ops are missing

[Paolo Abeni <pabeni@redhat.com>]

On 3/21/26 6:38 AM, Michal Piekos wrote:
> stmmac_vlan_restore() unconditionally calls stmmac_vlan_update() when
> NETIF_F_VLAN_FEATURES is set. On platforms where priv->hw->vlan (or
> ->update_vlan_hash) is not provided, stmmac_update_vlan_hash() returns
> -EINVAL via stmmac_do_void_callback(), resulting in a spurious
> "Failed to restore VLANs" error even when no VLAN filtering is in use.
> 
> Check presence of VLAN HW FILTER flags before stmmac_vlan_update().
> 
> Tested on Orange Pi Zero 3.
> 
> Fixes: bd7ad51253a7 ("net: stmmac: Fix VLAN HW state restore")
> Signed-off-by: Michal Piekos <michal.piekos@mmpsystems.pl>
> ---
> This patch fixes a noisy "Failed to restore VLANs" message on platforms
> where stmmac VLAN hash ops are not implemented.
> stmmac_vlan_restore() calls stmmac_vlan_update() without checking for
> VLAN hash ops presence which results in -EINVAL. 
> ---
> Changes in v2:
> - Replace check for hash ops with check for HW FILTER flags
> - Link to v1: https://lore.kernel.org/r/20260314-vlan-restore-error-v1-1-4fc6c3e2115f@mmpsystems.pl
> ---
>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 6827c99bde8c..cfc0ce9cec9c 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -6863,7 +6863,8 @@ static int stmmac_vlan_restore(struct stmmac_priv *priv)
>  {
>  	int ret;
>  
> -	if (!(priv->dev->features & NETIF_F_VLAN_FEATURES))
> +	if (!(priv->dev->features &
> +	      (NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER)))
>  		return 0;
>  
>  	if (priv->hw->num_vlan)
Adding Russell.

It's not obvious to me that with this change the
restore_hw_vlan_rx_fltr() and vlan_update() callback are still invoked
in all the relevant driver/features permutation.

/P