diff --git a/src/core/nm-l3-ipv6ll.c b/src/core/nm-l3-ipv6ll.c
index e99f6f8902..a02fe7fabb 100644
--- a/src/core/nm-l3-ipv6ll.c
+++ b/src/core/nm-l3-ipv6ll.c
@@ -19,6 +19,7 @@ NM_UTILS_LOOKUP_STR_DEFINE(nm_l3_ipv6ll_state_to_string,
                            NML3IPv6LLState,
                            NM_UTILS_LOOKUP_DEFAULT_NM_ASSERT("???"),
                            NM_UTILS_LOOKUP_STR_ITEM(NM_L3_IPV6LL_STATE_NONE, "none"),
+                           NM_UTILS_LOOKUP_STR_ITEM(NM_L3_IPV6LL_STATE_DEFUNCT, "defunct"),
                            NM_UTILS_LOOKUP_STR_ITEM(NM_L3_IPV6LL_STATE_STARTING, "starting"),
                            NM_UTILS_LOOKUP_STR_ITEM(NM_L3_IPV6LL_STATE_DAD_IN_PROGRESS,
                                                     "dad-in-progress"),
diff --git a/src/core/nm-l3-ipv6ll.h b/src/core/nm-l3-ipv6ll.h
index 8125b5d06a..770a4268a3 100644
--- a/src/core/nm-l3-ipv6ll.h
+++ b/src/core/nm-l3-ipv6ll.h
@@ -11,15 +11,21 @@
 typedef struct _NML3IPv6LL NML3IPv6LL;
 
 typedef enum _nm_packed {
-
-    /* NONE is not actually used by NML3IPv6LL. This is a bogus placeholder
-     * state for external users. */
-    NM_L3_IPV6LL_STATE_NONE,
-
     NM_L3_IPV6LL_STATE_STARTING,
     NM_L3_IPV6LL_STATE_DAD_IN_PROGRESS,
     NM_L3_IPV6LL_STATE_READY,
     NM_L3_IPV6LL_STATE_DAD_FAILED,
+
+    /* The following flags are not actually use by NML3IPv6LL. They exist for
+     * convenience of the users, to encode additional states. */
+
+    /* IPv6LL is disabled */
+    NM_L3_IPV6LL_STATE_NONE,
+
+    /* We want to do IPv6LL, but something is missing so we cannot even create
+     * a NML3IPv6LL instance. For example, no NML3Cfg instance or no interface name. */
+    NM_L3_IPV6LL_STATE_DEFUNCT,
+
 } NML3IPv6LLState;
 
 const char *nm_l3_ipv6ll_state_to_string(NML3IPv6LLState state);