diff --git a/block/nbd.c b/block/nbd.c
index 1b832c2..36ea617 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -421,6 +421,7 @@
             goto error;
         }
 
+        /* TODO SOCKET_ADDRESS_KIND_FD where fd has AF_INET or AF_INET6 */
         if (s->saddr->type != SOCKET_ADDRESS_KIND_INET) {
             error_setg(errp, "TLS only supported over IP sockets");
             goto error;
diff --git a/blockdev-nbd.c b/blockdev-nbd.c
index 7ea836b..8a11807 100644
--- a/blockdev-nbd.c
+++ b/blockdev-nbd.c
@@ -124,6 +124,7 @@
             goto error;
         }
 
+        /* TODO SOCKET_ADDRESS_KIND_FD where fd has AF_INET or AF_INET6 */
         if (addr->type != SOCKET_ADDRESS_KIND_INET) {
             error_setg(errp, "TLS is only supported with IPv4/IPv6");
             goto error;
diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index d7e92e1..6344b07 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -47,7 +47,6 @@
     int max_size;
     int do_telnetopt;
     int do_nodelay;
-    int is_unix;
     int *read_msgfds;
     size_t read_msgfds_num;
     int *write_msgfds;
@@ -825,7 +824,6 @@
     int64_t reconnect   = sock->has_reconnect ? sock->reconnect : 0;
     QIOChannelSocket *sioc = NULL;
 
-    s->is_unix = addr->type == SOCKET_ADDRESS_KIND_UNIX;
     s->is_listen = is_listen;
     s->is_telnet = is_telnet;
     s->do_nodelay = do_nodelay;
@@ -865,7 +863,8 @@
     s->addr = QAPI_CLONE(SocketAddress, sock->addr);
 
     qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE);
-    if (s->is_unix) {
+    /* TODO SOCKET_ADDRESS_FD where fd has AF_UNIX */
+    if (addr->type == SOCKET_ADDRESS_KIND_UNIX) {
         qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_FD_PASS);
     }
 
diff --git a/ui/vnc.c b/ui/vnc.c
index 243e99b..1095f9d 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -3642,6 +3642,7 @@
         error_setg(errp, "Expected a single address in reverse mode");
         return -1;
     }
+    /* TODO SOCKET_ADDRESS_KIND_FD when fd has AF_UNIX */
     vd->is_unix = saddr[0]->type == SOCKET_ADDRESS_KIND_UNIX;
     sioc = qio_channel_socket_new();
     qio_channel_set_name(QIO_CHANNEL(sioc), "vnc-reverse");
diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c
index 40164bf..9b73681 100644
--- a/util/qemu-sockets.c
+++ b/util/qemu-sockets.c
@@ -1154,6 +1154,10 @@
 {
     int fd;
 
+    /*
+     * TODO SOCKET_ADDRESS_KIND_FD when fd is AF_INET or AF_INET6
+     * (although other address families can do SOCK_DGRAM, too)
+     */
     switch (remote->type) {
     case SOCKET_ADDRESS_KIND_INET:
         fd = inet_dgram_saddr(remote->u.inet.data,