diff --git a/activate.c b/activate.c
index 13366c8..c8453d5 100644
--- a/activate.c
+++ b/activate.c
@@ -84,11 +84,14 @@ static void activate_mapping(struct irq_info *info, void *data __attribute__((un
 		if ((info->hint_policy == HINT_POLICY_SUBSET) &&
 		    (!cpus_empty(info->affinity_hint))) {
 			cpus_and(applied_mask, applied_mask, info->affinity_hint);
-			if (!cpus_intersects(applied_mask, unbanned_cpus))
-				log(TO_ALL, LOG_WARNING,
-				    "irq %d affinity_hint subset empty\n",
-				   info->irq);
-			else
+			if (!cpus_intersects(applied_mask, unbanned_cpus)) {
+				if (!info->warned) {
+					info->warned = 1;
+					log(TO_ALL, LOG_WARNING,
+					    "irq %d affinity_hint subset empty\n",
+					    info->irq);
+				}
+			} else
 				valid_mask = 1;
 		} else {
 			valid_mask = 1;