diff --git a/daemon/aux.h b/daemon/aux.h
index 51aab5bc3..6eaa2305a 100644
--- a/daemon/aux.h
+++ b/daemon/aux.h
@@ -474,34 +474,40 @@ INLINE int family_from_address(const struct in6_addr *a) {
 }
 
 /* checks if at least one of the flags is set */
-INLINE int bf_isset(const unsigned int *u, unsigned int f) {
-	if ((*u & f))
+INLINE int bf_isset(const volatile unsigned int *u, unsigned int f) {
+	if ((g_atomic_int_get(u) & f))
 		return -1;
 	return 0;
 }
-INLINE void bf_set(unsigned int *u, unsigned int f) {
-	*u |= f;
+INLINE void bf_set(volatile unsigned int *u, unsigned int f) {
+	g_atomic_int_or(u, f);
 }
-INLINE void bf_clear(unsigned int *u, unsigned int f) {
-	*u &= ~f;
+INLINE void bf_clear(volatile unsigned int *u, unsigned int f) {
+	g_atomic_int_and(u, ~f);
 }
-INLINE void bf_xset(unsigned int *u, unsigned int f, int cond) {
-	bf_clear(u, f);
-	bf_set(u, cond ? f : 0);
+INLINE void bf_set_clear(volatile unsigned int *u, unsigned int f, int cond) {
+	if (cond)
+		bf_set(u, f);
+	else
+		bf_clear(u, f);
 }
 /* works only for single flags */
-INLINE void bf_copy(unsigned int *u, unsigned int f, const unsigned int *s, unsigned int g) {
-	/* a good compiler will optimize out the calls to log2() */
-	*u &= ~f;
-	if (f >= g)
-		*u |= (*s & g) << (int) (log2(f) - log2(g));
-	else
-		*u |= (*s & g) >> (int) (log2(g) - log2(f));
+INLINE void bf_copy(volatile unsigned int *u, unsigned int f,
+		const volatile unsigned int *s, unsigned int g)
+{
+	bf_set_clear(u, f, bf_isset(s, g));
 }
 /* works for multiple flags */
-INLINE void bf_copy_same(unsigned int *u, const unsigned int *s, unsigned int g) {
-	bf_copy(u, g, s, g);
+INLINE void bf_copy_same(volatile unsigned int *u, const volatile unsigned int *s, unsigned int g) {
+	unsigned int old, set, clear;
+	old = g_atomic_int_get(s);
+	set = old & g;
+	clear = ~old & g;
+	bf_set(u, set);
+	bf_clear(u, clear);
 }
+
+
 INLINE void g_queue_append(GQueue *dst, const GQueue *src) {
 	GList *l;
 	if (!src || !dst)
diff --git a/daemon/call.h b/daemon/call.h
index 05c0321f1..3bd59810b 100644
--- a/daemon/call.h
+++ b/daemon/call.h
@@ -303,8 +303,7 @@ struct packet_stream {
 	X509			*dtls_cert;	/* LOCK: in_lock */
 
 	/* in_lock must be held for SETTING these: */
-	/* (XXX replace with atomic ops where appropriate) */
-	unsigned int		ps_flags;
+	volatile unsigned int	ps_flags;
 };
 
 /* protected by call->master_lock, except the RO elements */
@@ -337,7 +336,7 @@ struct call_media {
 	GSList			*endpoint_maps;
 	GHashTable		*rtp_payload_types;
 
-	unsigned int		media_flags;
+	volatile unsigned int	media_flags;
 };
 
 /* half a dialogue */
diff --git a/daemon/sdp.c b/daemon/sdp.c
index 45820d790..2a14fe6e9 100644
--- a/daemon/sdp.c
+++ b/daemon/sdp.c
@@ -1123,9 +1123,9 @@ int sdp_streams(const GQueue *sessions, GQueue *streams, struct sdp_ng_flags *fl
 			sp->type = media->media_type;
 			memcpy(sp->direction, flags->direction, sizeof(sp->direction));
 			sp->desired_family = flags->address_family;
-			bf_xset(&sp->sp_flags, SP_FLAG_ASYMMETRIC, flags->asymmetric);
-			bf_xset(&sp->sp_flags, SP_FLAG_STRICT_SOURCE, flags->strict_source);
-			bf_xset(&sp->sp_flags, SP_FLAG_MEDIA_HANDOVER, flags->media_handover);
+			bf_set_clear(&sp->sp_flags, SP_FLAG_ASYMMETRIC, flags->asymmetric);
+			bf_set_clear(&sp->sp_flags, SP_FLAG_STRICT_SOURCE, flags->strict_source);
+			bf_set_clear(&sp->sp_flags, SP_FLAG_MEDIA_HANDOVER, flags->media_handover);
 
 			errstr = "Invalid RTP payload types";
 			if (__rtp_payload_types(sp, media))