diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index fdacb864c3dd..2c5676b0a6e7 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -398,6 +398,17 @@ static int activate_reserved(struct irq_data *irqd)
 		if (!irqd_can_reserve(irqd))
 			apicd->can_reserve = false;
 	}
+
+	/*
+	 * Check to ensure that the effective affinity mask is a subset
+	 * the user supplied affinity mask, and warn the user if it is not
+	 */
+	if (!cpumask_subset(irq_data_get_effective_affinity_mask(irqd),
+			    irq_data_get_affinity_mask(irqd))) {
+		pr_warn("irq %u: Affinity broken due to vector space exhaustion.\n",
+			irqd->irq);
+	}
+
 	return ret;
 }