리눅스 커널 프로토콜 추가

insmod: error inserting 'igmps.ko': -1 Resource temporarily unavailable

WARNING: "inet_protos" [/home/gaedol/tmp/igmps.ko] undefined!

Mar 19 08:01:36 embedded kernel: [17180571.424000] igmps: Unknown symbol inet_protos

-- 상략 --
 
static struct net_protocol igmps_protocol = {
	.handler 	= igmps_rcv,
};
 
#ifdef MODULE
void __exit igmps_cleanup(void)
{
	inet_del_protocol(&igmps_protocol, IPPROTO_IGMP);
	inet_add_protocol(&igmp_protocol, IPPROTO_IGMP);
}
#endif
 
int __init igmps_init(void)
{
	int hash = IPPROTO_IGMP & (MAX_INET_PROTOS - 1);
 
	igmp_protocol = inet_protos[hash]; // inet_protos 심볼을 참조하는 부분
 
	inet_del_protocol(igmp_protocol, IPPROTO_IGMP);
 
	if(inet_add_protocol(&igmps_protocol, IPPROTO_IGMP) < 0) {
		printk(KERN_INFO "igmps init: Can't add protocol\n");
		return -EAGAIN;
	}
	return 0;
}
 
 
module_init(igmps_init);
module_exit(igmps_cleanup);