netdev - ip_list_rcv() question

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Message-ID: <20211007121451.GA27153@EXT-6P2T573.localdomain>
Date:   Thu, 7 Oct 2021 08:14:51 -0400
From:   Stephen Suryaputra <ssuryaextr@...il.com>
To:     netdev@...r.kernel.org
Subject: ip_list_rcv() question

Hi,

Under what condition that ip_list_rcv() would restart the sublist, i.e.
that the skb in the list is having different skb->dev?

void ip_list_rcv(struct list_head *head, struct packet_type *pt,
		 struct net_device *orig_dev)
{
	...
	list_for_each_entry_safe(skb, next, head, list) {
		...
		if (curr_dev != dev || curr_net != net) {
			/* dispatch old sublist */
			...
			/* start new sublist */
			...
		}
		...
	}
	...
}

In my system, the function gets called from the following call chain:
net_rx_action()->napi_poll()->gro_normal_list()

It seems to me that there is one to one relationship between napi_struct
and net_device, but I saw an archived discussion about it might be one
to many. But I didn't see it.

Thanks in advance for the clarifications.

Regards,
Stephen.