[PATCH v3] net: stmmac: skip VLAN restore when VLAN hash ops are missing

[Michal Piekos]

On Sat, Mar 28, 2026 at 07:51:20AM +0000, Russell King (Oracle) wrote:
> On Sat, Mar 28, 2026 at 07:51:53AM +0100, 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.
> > 
> > Remove the unneeded comment.
> > 
> > Tested on Orange Pi Zero 3.
> > 
> > Fixes: bd7ad51253a7 ("net: stmmac: Fix VLAN HW state restore")
> > Signed-off-by: Michal Piekos <michal.piekos at 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 v3:
> > - Remove the offending comment
> > - Restore the original check for NETIF_F_VLAN_FEATURES
> > - Link to v2: https://lore.kernel.org/r/20260321-vlan-restore-error-v2-1-45cf56a5223d@mmpsystems.pl
> > 
> > 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 | 8 +-------
> >  1 file changed, 1 insertion(+), 7 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > index 6827c99bde8c..0f3e5ac05faa 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > @@ -6861,19 +6861,13 @@ static int stmmac_vlan_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vi
> >  
> >  static int stmmac_vlan_restore(struct stmmac_priv *priv)
> >  {
> > -	int ret;
> > -
> >  	if (!(priv->dev->features & NETIF_F_VLAN_FEATURES))
> >  		return 0;
> >  
> >  	if (priv->hw->num_vlan)
> >  		stmmac_restore_hw_vlan_rx_fltr(priv, priv->dev, priv->hw);
> >  
> > -	ret = stmmac_vlan_update(priv, priv->num_double_vlans);
> > -	if (ret)
> > -		netdev_err(priv->dev, "Failed to restore VLANs\n");
> > -
> > -	return ret;
> > +	return stmmac_vlan_update(priv, priv->num_double_vlans);
> >  }
> 
> Yes, but as both Andrew and myself have pointed out, no one checks
> the return value of stmmac_vlan_restore(), so why does it return
> int?

Was too quick with the patch. Will spin another version.

Michal
> 
> -- 
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