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

[Jijie Shao <shaojijie@huawei.com>]

on 2024/10/24 20:07, Andrew Lunn wrote:
> On Thu, Oct 24, 2024 at 11:09:22AM +0800, Jijie Shao wrote:
>> on 2024/10/23 22:05, Andrew Lunn wrote:
>>>> +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!