커널컴파일 에러 좀 알려주세요.

커널 컴파일중 마지막 부분에 다음과 같은
에러(?)가 발생하면서 멈춤니다.

이유가 뭘까요?

LD net/xfrm/built-in.o
LD net/built-in.o
GEN .version
CHK include/linux/compile.h
UPD include/linux/compile.h
CC init/version.o
LD init/built-in.o
LD .tmp_vmlinux1
net/built-in.o(.text+0x59a94): In function `__xfrm_policy_check':
: undefined reference to `secpath_has_tunnel'
net/built-in.o(.text+0x62874): In function `xfrm_send_migrate':
xfrm_user.c: undefined reference to `build_migrate'
net/built-in.o(.text+0x676fc): In function `ipv6_sock_ac_join':
: undefined reference to `rt6_tb_lookup'
net/built-in.o(.text+0x70444): In function `addrconf_prefix_rcv':
: undefined reference to `rt6_tb_lookup'
net/built-in.o(.text+0x74240): In function `ip6_pol_route_lookup':
: undefined reference to `BACKTRACK'
net/built-in.o(.text+0x74778): In function `ip6_pol_route_input':
: undefined reference to `BACKTRACK'
net/built-in.o(.text+0x748b8): In function `ip6_pol_route_input':
: undefined reference to `BACKTRACK'
net/built-in.o(.text+0x74b8c): In function `ip6_pol_route_output':
: undefined reference to `BACKTRACK'
net/built-in.o(.text+0x74c58): In function `ip6_pol_route_output':
: undefined reference to `BACKTRACK'
net/built-in.o(.init.text+0xed4): In function `tcp_init':
: undefined reference to `__skb_cb_too_small_for_tcp'
net/built-in.o(__ksymtab+0xe98): undefined reference to `rt6_lock'
net/built-in.o(__ksymtab+0xed8): undefined reference to `rt6_fl_tree_lookup'