diff --git a/hostapd/Makefile b/hostapd/Makefile
index 87ff9b4fe..b4704bafa 100644
--- a/hostapd/Makefile
+++ b/hostapd/Makefile
@@ -84,6 +84,14 @@ CONFIG_ELOOP=eloop
 endif
 OBJS += ../src/utils/$(CONFIG_ELOOP).o
 OBJS_c += ../src/utils/$(CONFIG_ELOOP).o
+
+ifeq ($(CONFIG_ELOOP), eloop)
+# Using glibc < 2.17 requires -lrt for clock_gettime()
+LIBS += -lrt
+LIBS_c += -lrt
+LIBS_h += -lrt
+endif
+
 OBJS += ../src/utils/common.o
 OBJS += ../src/utils/wpa_debug.o
 OBJS_c += ../src/utils/wpa_debug.o
diff --git a/src/utils/eloop.c b/src/utils/eloop.c
index 2d6aac7e0..e983edcfb 100644
--- a/src/utils/eloop.c
+++ b/src/utils/eloop.c
@@ -31,7 +31,7 @@ struct eloop_sock {
 
 struct eloop_timeout {
 	struct dl_list list;
-	struct os_time time;
+	struct os_reltime time;
 	void *eloop_data;
 	void *user_data;
 	eloop_timeout_handler handler;
@@ -484,7 +484,7 @@ int eloop_register_timeout(unsigned int secs, unsigned int usecs,
 	timeout = os_zalloc(sizeof(*timeout));
 	if (timeout == NULL)
 		return -1;
-	if (os_get_time(&timeout->time) < 0) {
+	if (os_get_reltime(&timeout->time) < 0) {
 		os_free(timeout);
 		return -1;
 	}
@@ -514,7 +514,7 @@ int eloop_register_timeout(unsigned int secs, unsigned int usecs,
 
 	/* Maintain timeouts in order of increasing time */
 	dl_list_for_each(tmp, &eloop.timeout, struct eloop_timeout, list) {
-		if (os_time_before(&timeout->time, &tmp->time)) {
+		if (os_reltime_before(&timeout->time, &tmp->time)) {
 			dl_list_add(tmp->list.prev, &timeout->list);
 			return 0;
 		}
@@ -558,13 +558,13 @@ int eloop_cancel_timeout(eloop_timeout_handler handler,
 
 int eloop_cancel_timeout_one(eloop_timeout_handler handler,
 			     void *eloop_data, void *user_data,
-			     struct os_time *remaining)
+			     struct os_reltime *remaining)
 {
 	struct eloop_timeout *timeout, *prev;
 	int removed = 0;
-	struct os_time now;
+	struct os_reltime now;
 
-	os_get_time(&now);
+	os_get_reltime(&now);
 	remaining->sec = remaining->usec = 0;
 
 	dl_list_for_each_safe(timeout, prev, &eloop.timeout,
@@ -573,8 +573,8 @@ int eloop_cancel_timeout_one(eloop_timeout_handler handler,
 		    (timeout->eloop_data == eloop_data) &&
 		    (timeout->user_data == user_data)) {
 			removed = 1;
-			if (os_time_before(&now, &timeout->time))
-				os_time_sub(&timeout->time, &now, remaining);
+			if (os_reltime_before(&now, &timeout->time))
+				os_reltime_sub(&timeout->time, &now, remaining);
 			eloop_remove_timeout(timeout);
 			break;
 		}
@@ -603,7 +603,7 @@ int eloop_deplete_timeout(unsigned int req_secs, unsigned int req_usecs,
 			  eloop_timeout_handler handler, void *eloop_data,
 			  void *user_data)
 {
-	struct os_time now, requested, remaining;
+	struct os_reltime now, requested, remaining;
 	struct eloop_timeout *tmp;
 
 	dl_list_for_each(tmp, &eloop.timeout, struct eloop_timeout, list) {
@@ -612,9 +612,9 @@ int eloop_deplete_timeout(unsigned int req_secs, unsigned int req_usecs,
 		    tmp->user_data == user_data) {
 			requested.sec = req_secs;
 			requested.usec = req_usecs;
-			os_get_time(&now);
-			os_time_sub(&tmp->time, &now, &remaining);
-			if (os_time_before(&requested, &remaining)) {
+			os_get_reltime(&now);
+			os_reltime_sub(&tmp->time, &now, &remaining);
+			if (os_reltime_before(&requested, &remaining)) {
 				eloop_cancel_timeout(handler, eloop_data,
 						     user_data);
 				eloop_register_timeout(requested.sec,
@@ -634,7 +634,7 @@ int eloop_replenish_timeout(unsigned int req_secs, unsigned int req_usecs,
 			    eloop_timeout_handler handler, void *eloop_data,
 			    void *user_data)
 {
-	struct os_time now, requested, remaining;
+	struct os_reltime now, requested, remaining;
 	struct eloop_timeout *tmp;
 
 	dl_list_for_each(tmp, &eloop.timeout, struct eloop_timeout, list) {
@@ -643,9 +643,9 @@ int eloop_replenish_timeout(unsigned int req_secs, unsigned int req_usecs,
 		    tmp->user_data == user_data) {
 			requested.sec = req_secs;
 			requested.usec = req_usecs;
-			os_get_time(&now);
-			os_time_sub(&tmp->time, &now, &remaining);
-			if (os_time_before(&remaining, &requested)) {
+			os_get_reltime(&now);
+			os_reltime_sub(&tmp->time, &now, &remaining);
+			if (os_reltime_before(&remaining, &requested)) {
 				eloop_cancel_timeout(handler, eloop_data,
 						     user_data);
 				eloop_register_timeout(requested.sec,
@@ -776,7 +776,7 @@ void eloop_run(void)
 	struct timeval _tv;
 #endif /* CONFIG_ELOOP_POLL */
 	int res;
-	struct os_time tv, now;
+	struct os_reltime tv, now;
 
 #ifndef CONFIG_ELOOP_POLL
 	rfds = os_malloc(sizeof(*rfds));
@@ -793,9 +793,9 @@ void eloop_run(void)
 		timeout = dl_list_first(&eloop.timeout, struct eloop_timeout,
 					list);
 		if (timeout) {
-			os_get_time(&now);
-			if (os_time_before(&now, &timeout->time))
-				os_time_sub(&timeout->time, &now, &tv);
+			os_get_reltime(&now);
+			if (os_reltime_before(&now, &timeout->time))
+				os_reltime_sub(&timeout->time, &now, &tv);
 			else
 				tv.sec = tv.usec = 0;
 #ifdef CONFIG_ELOOP_POLL
@@ -837,8 +837,8 @@ void eloop_run(void)
 		timeout = dl_list_first(&eloop.timeout, struct eloop_timeout,
 					list);
 		if (timeout) {
-			os_get_time(&now);
-			if (!os_time_before(&now, &timeout->time)) {
+			os_get_reltime(&now);
+			if (!os_reltime_before(&now, &timeout->time)) {
 				void *eloop_data = timeout->eloop_data;
 				void *user_data = timeout->user_data;
 				eloop_timeout_handler handler =
@@ -883,9 +883,9 @@ void eloop_terminate(void)
 void eloop_destroy(void)
 {
 	struct eloop_timeout *timeout, *prev;
-	struct os_time now;
+	struct os_reltime now;
 
-	os_get_time(&now);
+	os_get_reltime(&now);
 	dl_list_for_each_safe(timeout, prev, &eloop.timeout,
 			      struct eloop_timeout, list) {
 		int sec, usec;
diff --git a/src/utils/eloop.h b/src/utils/eloop.h
index 274714f88..d3980fa49 100644
--- a/src/utils/eloop.h
+++ b/src/utils/eloop.h
@@ -207,7 +207,7 @@ int eloop_cancel_timeout(eloop_timeout_handler handler,
  */
 int eloop_cancel_timeout_one(eloop_timeout_handler handler,
 			     void *eloop_data, void *user_data,
-			     struct os_time *remaining);
+			     struct os_reltime *remaining);
 
 /**
  * eloop_is_timeout_registered - Check if a timeout is already registered
diff --git a/src/utils/eloop_win.c b/src/utils/eloop_win.c
index e87d82ac9..a1f999648 100644
--- a/src/utils/eloop_win.c
+++ b/src/utils/eloop_win.c
@@ -31,7 +31,7 @@ struct eloop_event {
 
 struct eloop_timeout {
 	struct dl_list list;
-	struct os_time time;
+	struct os_reltime time;
 	void *eloop_data;
 	void *user_data;
 	eloop_timeout_handler handler;
@@ -244,7 +244,7 @@ int eloop_register_timeout(unsigned int secs, unsigned int usecs,
 	timeout = os_zalloc(sizeof(*timeout));
 	if (timeout == NULL)
 		return -1;
-	if (os_get_time(&timeout->time) < 0) {
+	if (os_get_reltime(&timeout->time) < 0) {
 		os_free(timeout);
 		return -1;
 	}
@@ -271,7 +271,7 @@ int eloop_register_timeout(unsigned int secs, unsigned int usecs,
 
 	/* Maintain timeouts in order of increasing time */
 	dl_list_for_each(tmp, &eloop.timeout, struct eloop_timeout, list) {
-		if (os_time_before(&timeout->time, &tmp->time)) {
+		if (os_reltime_before(&timeout->time, &tmp->time)) {
 			dl_list_add(tmp->list.prev, &timeout->list);
 			return 0;
 		}
@@ -313,13 +313,13 @@ int eloop_cancel_timeout(eloop_timeout_handler handler,
 
 int eloop_cancel_timeout_one(eloop_timeout_handler handler,
 			     void *eloop_data, void *user_data,
-			     struct os_time *remaining)
+			     struct os_reltime *remaining)
 {
 	struct eloop_timeout *timeout, *prev;
 	int removed = 0;
-	struct os_time now;
+	struct os_reltime now;
 
-	os_get_time(&now);
+	os_get_reltime(&now);
 	remaining->sec = remaining->usec = 0;
 
 	dl_list_for_each_safe(timeout, prev, &eloop.timeout,
@@ -328,8 +328,8 @@ int eloop_cancel_timeout_one(eloop_timeout_handler handler,
 		    (timeout->eloop_data == eloop_data) &&
 		    (timeout->user_data == user_data)) {
 			removed = 1;
-			if (os_time_before(&now, &timeout->time))
-				os_time_sub(&timeout->time, &now, remaining);
+			if (os_reltime_before(&now, &timeout->time))
+				os_reltime_sub(&timeout->time, &now, remaining);
 			eloop_remove_timeout(timeout);
 			break;
 		}
@@ -358,7 +358,7 @@ int eloop_deplete_timeout(unsigned int req_secs, unsigned int req_usecs,
 			  eloop_timeout_handler handler, void *eloop_data,
 			  void *user_data)
 {
-	struct os_time now, requested, remaining;
+	struct os_reltime now, requested, remaining;
 	struct eloop_timeout *tmp;
 
 	dl_list_for_each(tmp, &eloop.timeout, struct eloop_timeout, list) {
@@ -367,9 +367,9 @@ int eloop_deplete_timeout(unsigned int req_secs, unsigned int req_usecs,
 		    tmp->user_data == user_data) {
 			requested.sec = req_secs;
 			requested.usec = req_usecs;
-			os_get_time(&now);
-			os_time_sub(&tmp->time, &now, &remaining);
-			if (os_time_before(&requested, &remaining)) {
+			os_get_reltime(&now);
+			os_reltime_sub(&tmp->time, &now, &remaining);
+			if (os_reltime_before(&requested, &remaining)) {
 				eloop_cancel_timeout(handler, eloop_data,
 						     user_data);
 				eloop_register_timeout(requested.sec,
@@ -389,7 +389,7 @@ int eloop_replenish_timeout(unsigned int req_secs, unsigned int req_usecs,
 			    eloop_timeout_handler handler, void *eloop_data,
 			    void *user_data)
 {
-	struct os_time now, requested, remaining;
+	struct os_reltime now, requested, remaining;
 	struct eloop_timeout *tmp;
 
 	dl_list_for_each(tmp, &eloop.timeout, struct eloop_timeout, list) {
@@ -398,9 +398,9 @@ int eloop_replenish_timeout(unsigned int req_secs, unsigned int req_usecs,
 		    tmp->user_data == user_data) {
 			requested.sec = req_secs;
 			requested.usec = req_usecs;
-			os_get_time(&now);
-			os_time_sub(&tmp->time, &now, &remaining);
-			if (os_time_before(&remaining, &requested)) {
+			os_get_reltime(&now);
+			os_reltime_sub(&tmp->time, &now, &remaining);
+			if (os_reltime_before(&remaining, &requested)) {
 				eloop_cancel_timeout(handler, eloop_data,
 						     user_data);
 				eloop_register_timeout(requested.sec,
@@ -530,7 +530,7 @@ int eloop_register_signal_reconfig(eloop_signal_handler handler,
 
 void eloop_run(void)
 {
-	struct os_time tv, now;
+	struct os_reltime tv, now;
 	DWORD count, ret, timeout_val, err;
 	size_t i;
 
@@ -542,9 +542,9 @@ void eloop_run(void)
 		timeout = dl_list_first(&eloop.timeout, struct eloop_timeout,
 					list);
 		if (timeout) {
-			os_get_time(&now);
-			if (os_time_before(&now, &timeout->time))
-				os_time_sub(&timeout->time, &now, &tv);
+			os_get_reltime(&now);
+			if (os_reltime_before(&now, &timeout->time))
+				os_reltime_sub(&timeout->time, &now, &tv);
 		}
 
 		count = 0;
@@ -583,8 +583,8 @@ void eloop_run(void)
 		timeout = dl_list_first(&eloop.timeout, struct eloop_timeout,
 					list);
 		if (timeout) {
-			os_get_time(&now);
-			if (!os_time_before(&now, &timeout->time)) {
+			os_get_reltime(&now);
+			if (!os_reltime_before(&now, &timeout->time)) {
 				void *eloop_data = timeout->eloop_data;
 				void *user_data = timeout->user_data;
 				eloop_timeout_handler handler =
diff --git a/src/utils/os.h b/src/utils/os.h
index 2aab13af0..77dc6e38a 100644
--- a/src/utils/os.h
+++ b/src/utils/os.h
@@ -23,6 +23,11 @@ struct os_time {
 	os_time_t usec;
 };
 
+struct os_reltime {
+	os_time_t sec;
+	os_time_t usec;
+};
+
 /**
  * os_get_time - Get current time (sec, usec)
  * @t: Pointer to buffer for the time
@@ -30,21 +35,56 @@ struct os_time {
  */
 int os_get_time(struct os_time *t);
 
+/**
+ * os_get_reltime - Get relative time (sec, usec)
+ * @t: Pointer to buffer for the time
+ * Returns: 0 on success, -1 on failure
+ */
+int os_get_reltime(struct os_reltime *t);
 
-/* Helper macros for handling struct os_time */
 
-#define os_time_before(a, b) \
-	((a)->sec < (b)->sec || \
-	 ((a)->sec == (b)->sec && (a)->usec < (b)->usec))
+/* Helpers for handling struct os_time */
+
+static inline int os_time_before(struct os_time *a, struct os_time *b)
+{
+	return (a->sec < b->sec) ||
+	       (a->sec == b->sec && a->usec < b->usec);
+}
+
+
+static inline void os_time_sub(struct os_time *a, struct os_time *b,
+			       struct os_time *res)
+{
+	res->sec = a->sec - b->sec;
+	res->usec = a->usec - b->usec;
+	if (res->usec < 0) {
+		res->sec--;
+		res->usec += 1000000;
+	}
+}
+
+
+/* Helpers for handling struct os_reltime */
+
+static inline int os_reltime_before(struct os_reltime *a,
+				    struct os_reltime *b)
+{
+	return (a->sec < b->sec) ||
+	       (a->sec == b->sec && a->usec < b->usec);
+}
+
+
+static inline void os_reltime_sub(struct os_reltime *a, struct os_reltime *b,
+				  struct os_reltime *res)
+{
+	res->sec = a->sec - b->sec;
+	res->usec = a->usec - b->usec;
+	if (res->usec < 0) {
+		res->sec--;
+		res->usec += 1000000;
+	}
+}
 
-#define os_time_sub(a, b, res) do { \
-	(res)->sec = (a)->sec - (b)->sec; \
-	(res)->usec = (a)->usec - (b)->usec; \
-	if ((res)->usec < 0) { \
-		(res)->sec--; \
-		(res)->usec += 1000000; \
-	} \
-} while (0)
 
 /**
  * os_mktime - Convert broken-down time into seconds since 1970-01-01
diff --git a/src/utils/os_internal.c b/src/utils/os_internal.c
index e4b7fdb18..2cb0d1262 100644
--- a/src/utils/os_internal.c
+++ b/src/utils/os_internal.c
@@ -41,6 +41,17 @@ int os_get_time(struct os_time *t)
 }
 
 
+int os_get_reltime(struct os_reltime *t)
+{
+	int res;
+	struct timeval tv;
+	res = gettimeofday(&tv, NULL);
+	t->sec = tv.tv_sec;
+	t->usec = tv.tv_usec;
+	return res;
+}
+
+
 int os_mktime(int year, int month, int day, int hour, int min, int sec,
 	      os_time_t *t)
 {
diff --git a/src/utils/os_none.c b/src/utils/os_none.c
index cabf73bd8..228c4724c 100644
--- a/src/utils/os_none.c
+++ b/src/utils/os_none.c
@@ -26,6 +26,12 @@ int os_get_time(struct os_time *t)
 }
 
 
+int os_get_reltime(struct os_reltime *t)
+{
+	return -1;
+}
+
+
 int os_mktime(int year, int month, int day, int hour, int min, int sec,
 	      os_time_t *t)
 {
diff --git a/src/utils/os_unix.c b/src/utils/os_unix.c
index 960073a50..fa67fdfb6 100644
--- a/src/utils/os_unix.c
+++ b/src/utils/os_unix.c
@@ -60,6 +60,43 @@ int os_get_time(struct os_time *t)
 }
 
 
+int os_get_reltime(struct os_reltime *t)
+{
+#if defined(CLOCK_BOOTTIME)
+	static clockid_t clock_id = CLOCK_BOOTTIME;
+#elif defined(CLOCK_MONOTONIC)
+	static clockid_t clock_id = CLOCK_MONOTONIC;
+#else
+	static clockid_t clock_id = CLOCK_REALTIME;
+#endif
+	struct timespec ts;
+	int res;
+
+	while (1) {
+		res = clock_gettime(clock_id, &ts);
+		if (res == 0) {
+			t->sec = ts.tv_sec;
+			t->usec = ts.tv_nsec / 1000;
+			return 0;
+		}
+		switch (clock_id) {
+#ifdef CLOCK_BOOTTIME
+		case CLOCK_BOOTTIME:
+			clock_id = CLOCK_MONOTONIC;
+			break;
+#endif
+#ifdef CLOCK_MONOTONIC
+		case CLOCK_MONOTONIC:
+			clock_id = CLOCK_REALTIME;
+			break;
+#endif
+		case CLOCK_REALTIME:
+			return -1;
+		}
+	}
+}
+
+
 int os_mktime(int year, int month, int day, int hour, int min, int sec,
 	      os_time_t *t)
 {
diff --git a/src/utils/os_win32.c b/src/utils/os_win32.c
index 163cebefc..1cfa7a5f8 100644
--- a/src/utils/os_win32.c
+++ b/src/utils/os_win32.c
@@ -47,6 +47,17 @@ int os_get_time(struct os_time *t)
 }
 
 
+int os_get_reltime(struct os_reltime *t)
+{
+	/* consider using performance counters or so instead */
+	struct os_time now;
+	int res = os_get_time(&now);
+	t->sec = now.sec;
+	t->usec = now.usec;
+	return res;
+}
+
+
 int os_mktime(int year, int month, int day, int hour, int min, int sec,
 	      os_time_t *t)
 {
diff --git a/wlantest/Makefile b/wlantest/Makefile
index a08fd547d..175fb515f 100644
--- a/wlantest/Makefile
+++ b/wlantest/Makefile
@@ -19,6 +19,8 @@ CFLAGS += -I.
 CFLAGS += -I../src
 CFLAGS += -I../src/utils
 
+# glibc < 2.17 needs -lrt for clock_gettime()
+LIBS += -lrt
 
 ifndef LDO
 LDO=$(CC)
@@ -112,7 +114,7 @@ wlantest: $(OBJS) $(LIBWLANTEST)
 	$(LDO) $(LDFLAGS) -o wlantest $(OBJS) -L. -lwlantest $(LIBS)
 
 wlantest_cli: $(OBJS_cli) $(LIBWLANTEST)
-	$(LDO) $(LDFLAGS) -o wlantest_cli $(OBJS_cli) -L. -lwlantest
+	$(LDO) $(LDFLAGS) -o wlantest_cli $(OBJS_cli) -L. -lwlantest $(LIBS)
 
 test_vectors: $(TOBJS) $(LIBWLANTEST)
 	$(LDO) $(LDFLAGS) -o test_vectors $(TOBJS) -L. -lwlantest $(LIBS)
diff --git a/wpa_supplicant/Makefile b/wpa_supplicant/Makefile
index 8dcb71b12..f6a46d28e 100644
--- a/wpa_supplicant/Makefile
+++ b/wpa_supplicant/Makefile
@@ -113,6 +113,13 @@ endif
 OBJS += ../src/utils/$(CONFIG_ELOOP).o
 OBJS_c += ../src/utils/$(CONFIG_ELOOP).o
 
+ifeq ($(CONFIG_ELOOP), eloop)
+# Using glibc < 2.17 requires -lrt for clock_gettime()
+LIBS += -lrt
+LIBS_c += -lrt
+LIBS_p += -lrt
+endif
+
 ifdef CONFIG_ELOOP_POLL
 CFLAGS += -DCONFIG_ELOOP_POLL
 endif
diff --git a/wpa_supplicant/scan.c b/wpa_supplicant/scan.c
index 7baacaa6f..625ff2860 100644
--- a/wpa_supplicant/scan.c
+++ b/wpa_supplicant/scan.c
@@ -884,7 +884,7 @@ scan:
 
 void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
 {
-	struct os_time remaining, new_int;
+	struct os_reltime remaining, new_int;
 	int cancelled;
 
 	cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
@@ -892,7 +892,7 @@ void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
 
 	new_int.sec = sec;
 	new_int.usec = 0;
-	if (cancelled && os_time_before(&remaining, &new_int)) {
+	if (cancelled && os_reltime_before(&remaining, &new_int)) {
 		new_int.sec = remaining.sec;
 		new_int.usec = remaining.usec;
 	}