Index: usr.sbin/bhyve/bhyve.8
===================================================================
--- usr.sbin/bhyve/bhyve.8
+++ usr.sbin/bhyve/bhyve.8
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd March 18, 2021
+.Dd April 6, 2021
 .Dt BHYVE 8
 .Os
 .Sh NAME
@@ -133,16 +133,22 @@
 .Nm
 to exit when a guest issues an access to an I/O port that is not emulated.
 This is intended for debug purposes.
-.It Fl G Ar port
+.It Fl G Xo
+.Sm off
+.Oo Ar w Oc
+.Oo Ar bind_address: Oc
+.Ar port
+.Sm on
+.Xc
 Start a debug server that uses the GDB protocol to export guest state to a
 debugger.
 An IPv4 TCP socket will be bound to the supplied
+.Ar bind_address
+and
 .Ar port
 to listen for debugger connections.
 Only a single debugger may be attached to the debug server at a time.
-If
-.Ar port
-begins with
+If the option begins with
 .Sq w ,
 .Nm
 will pause execution at the first instruction waiting for a debugger to attach.
Index: usr.sbin/bhyve/bhyverun.c
===================================================================
--- usr.sbin/bhyve/bhyverun.c
+++ usr.sbin/bhyve/bhyverun.c
@@ -1255,11 +1255,7 @@
 			set_config_bool("memory.guest_in_core", true);
 			break;
 		case 'G':
-			if (optarg[0] == 'w') {
-				set_config_bool("gdb.wait", true);
-				optarg++;
-			}
-			set_config_value("gdb.port", optarg);
+			set_config_value("gdb.address", optarg);
 			break;
 		case 'k':
 			parse_simple_config_file(optarg);
@@ -1446,10 +1442,7 @@
 	if (get_config_bool("acpi_tables"))
 		vmgenc_init(ctx);
 
-	value = get_config_value("gdb.port");
-	if (value != NULL)
-		init_gdb(ctx, atoi(value), get_config_bool_default("gdb.wait",
-		    false));
+	init_gdb(ctx, get_config_value("gdb.address"));
 
 	if (lpc_bootrom()) {
 		if (vm_set_capability(ctx, BSP, VM_CAP_UNRESTRICTED_GUEST, 1)) {
Index: usr.sbin/bhyve/gdb.h
===================================================================
--- usr.sbin/bhyve/gdb.h
+++ usr.sbin/bhyve/gdb.h
@@ -34,6 +34,6 @@
 void	gdb_cpu_breakpoint(int vcpu, struct vm_exit *vmexit);
 void	gdb_cpu_mtrap(int vcpu);
 void	gdb_cpu_suspend(int vcpu);
-void	init_gdb(struct vmctx *ctx, int sport, bool wait);
+void	init_gdb(struct vmctx *ctx, const char *optarg);
 
 #endif /* !__GDB_H__ */
Index: usr.sbin/bhyve/gdb.c
===================================================================
--- usr.sbin/bhyve/gdb.c
+++ usr.sbin/bhyve/gdb.c
@@ -48,6 +48,7 @@
 #include <err.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <netdb.h>
 #include <pthread.h>
 #include <pthread_np.h>
 #include <stdbool.h>
@@ -1817,13 +1818,60 @@
 }
 #endif
 
+static void
+parse_gdb_options(char *optarg, const char **saddr, const char **sport, bool *wait)
+{
+	char *colon;
+
+	if (optarg[0] == 'w') {
+		*wait = true;
+		optarg++;
+	} else {
+		*wait = false;
+	}
+
+	colon = strrchr(optarg, ':');
+	if (colon == NULL) {
+		*saddr = NULL;
+		*sport = optarg;
+		return;
+	}
+
+	*colon = '\0';
+	colon++;
+	*saddr = optarg;
+	*sport = colon;
+}
+
 void
-init_gdb(struct vmctx *_ctx, int sport, bool wait)
+init_gdb(struct vmctx *_ctx, const char *optarg)
 {
-	struct sockaddr_in sin;
 	int error, flags, s;
+	struct addrinfo hints;
+	struct addrinfo *gdbaddr;
+	const char *saddr, *sport;
+	bool wait;
+	char *str;
 
-	debug("==> starting on %d, %swaiting\n", sport, wait ? "" : "not ");
+	if (optarg == NULL)
+		return;
+
+	str = strdup(optarg);
+	if (str == NULL)
+		errx(4, "Failed to allocate memory");
+
+	parse_gdb_options(str, &saddr, &sport, &wait);
+
+	if (!saddr) {
+#if defined(INET)
+		saddr = "0.0.0.0";
+#elif defined(INET6)
+		saddr = "[::]";
+#endif
+	}
+
+	debug("==> starting on %s:%s, %swaiting\n",
+	    saddr, sport, wait ? "" : "not ");
 
 	error = pthread_mutex_init(&gdb_lock, NULL);
 	if (error != 0)
@@ -1832,17 +1880,20 @@
 	if (error != 0)
 		errc(1, error, "gdb cv init");
 
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV | AI_PASSIVE;
+
+	if (getaddrinfo(saddr, sport, &hints, &gdbaddr) != 0)
+		err(1, "gdb address resolve");
+
 	ctx = _ctx;
-	s = socket(PF_INET, SOCK_STREAM, 0);
+	s = socket(gdbaddr->ai_family, gdbaddr->ai_socktype, 0);
 	if (s < 0)
 		err(1, "gdb socket create");
 
-	sin.sin_len = sizeof(sin);
-	sin.sin_family = AF_INET;
-	sin.sin_addr.s_addr = htonl(INADDR_ANY);
-	sin.sin_port = htons(sport);
-
-	if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0)
+	if (bind(s, gdbaddr->ai_addr, gdbaddr->ai_addrlen) < 0)
 		err(1, "gdb socket bind");
 
 	if (listen(s, 1) < 0)
@@ -1871,4 +1922,6 @@
 #endif
 	mevent_add(s, EVF_READ, new_connection, NULL);
 	gdb_active = true;
+	freeaddrinfo(gdbaddr);
+	free(str);
 }