Re: [PATCH net-next 3/7] net: hibmcge: Add unicast frame filter supported in this module

on 2024/10/24 20:07, Andrew Lunn wrote:

On Thu, Oct 24, 2024 at 11:09:22AM +0800, Jijie Shao wrote:

quoted

on 2024/10/23 22:05, Andrew Lunn wrote:

quoted

quoted

+static int hbg_add_mac_to_filter(struct hbg_priv *priv, const u8 *addr)
+{
+	u32 index;
+
+	/* already exists */
+	if (!hbg_get_index_from_mac_table(priv, addr, &index))
+		return 0;
+
+	for (index = 0; index < priv->filter.table_max_len; index++)
+		if (is_zero_ether_addr(priv->filter.mac_table[index].addr)) {
+			hbg_set_mac_to_mac_table(priv, index, addr);
+			return 0;
+		}
+
+	if (!priv->filter.table_overflow) {
+		priv->filter.table_overflow = true;
+		hbg_update_promisc_mode(priv->netdev);
+		dev_info(&priv->pdev->dev, "mac table is overflow\n");
+	}
+
+	return -ENOSPC;

I _think_ this is wrong. If you run out of hardware resources, you
should change the interface to promiscuous mode and let the stack do
the filtering. Offloading it to hardware is just an acceleration,
nothing more.

	Andrew

In hbg_update_promisc_mode():
priv->filter.enabled = !(priv->filter.table_overflow || (netdev->flags & IFF_PROMISC));
hbg_hw_set_mac_filter_enable(priv, priv->filter.enabled);

if table_overflow， and netdev->flags not set IFF_PROMISC，
the priv->filter.enabled will set to false， Then， The MAC filter will be closed.
I think it's probably the same thing you said

In this:
+	if (!priv->filter.table_overflow) {
+		priv->filter.table_overflow = true;
+		hbg_update_promisc_mode(priv->netdev);
+		dev_info(&priv->pdev->dev, "mac table is overflow\n");
+	}
+
+	return -ENOSPC;

When the first overflow occurs, a log is printed, the MAC filter will be disabled, and -ENOSPC is returned.
If continue to add MAC addresses, -ENOSPC is returned only.

This is not obvious from a quick look at the code. Maybe a comment
would be good.

	Andrew

ok, Thanks!