Hi, struct neighbour has a member named hh_cache; this hh_cache caches link layer headers to speed up transmission (instead filling them again and again for each packet).
The hh_cache struct is defined in linux/netdev.h. Its first member is hh_next, which is a pointer to hh_cache. I tried to think of scenarios where this hh_next pointer is used, and could not think of anything. Each neighbour has one ip address (the primary key), so it has one dev member (which is the net_device on which that primary key is configured), so it has one mac address (which is the dev_addr of net_device). So there should be only one entry in that hh_cache ; it should be the entry which its hh_data (the ethernet header) is composed from the dev_addr, the source MAC address, and the type. Can anybody give an example when hh_cache of a neighbour instance is a list with more than one entry ? Regards, Johnson -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
