Re: ip_list_rcv() question

On Wed, Oct 13, 2021 at 05:17:51PM +0100, Edward Cree wrote:

On 07/10/2021 13:14, Stephen Suryaputra wrote:

quoted

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

IIRC, something earlier in the call chain (possibly
 __netif_receive_skb_core()?) can change skb->dev to something other
 than the device that originally received the packet (orig_dev).  I
 think it's if the packet gets handled/transformed by a software
 netdevice (maybe a VLAN device?).
But really when I wrote ip_list_rcv() I just worked on the basis
 that "I don't know it can't change, so I shall assume it can".

I see now that vlan_do_receive() changes the skb->dev. It didn't occur
to me because __netif_receive_skb_list_core() has a similar logic for
dispatching sublists. But still the skb->dev could be different that
orig_dev.

Thanks.