diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c
index 61317f4be444..72ae414e4d49 100644
--- a/arch/i386/kernel/io_apic.c
+++ b/arch/i386/kernel/io_apic.c
@@ -1163,14 +1163,15 @@ u8 irq_vector[NR_IRQ_VECTORS] __read_mostly = { FIRST_DEVICE_VECTOR , 0 };
 int assign_irq_vector(int irq)
 {
 	static int current_vector = FIRST_DEVICE_VECTOR, offset = 0;
+	unsigned long flags;
 	int vector;
 
 	BUG_ON(irq != AUTO_ASSIGN && (unsigned)irq >= NR_IRQ_VECTORS);
 
-	spin_lock(&vector_lock);
+	spin_lock_irqsave(&vector_lock, flags);
 
 	if (irq != AUTO_ASSIGN && IO_APIC_VECTOR(irq) > 0) {
-		spin_unlock(&vector_lock);
+		spin_unlock_irqrestore(&vector_lock, flags);
 		return IO_APIC_VECTOR(irq);
 	}
 next:
@@ -1181,7 +1182,7 @@ next:
 	if (current_vector >= FIRST_SYSTEM_VECTOR) {
 		offset++;
 		if (!(offset%8)) {
-			spin_unlock(&vector_lock);
+			spin_unlock_irqrestore(&vector_lock, flags);
 			return -ENOSPC;
 		}
 		current_vector = FIRST_DEVICE_VECTOR + offset;
@@ -1192,7 +1193,7 @@ next:
 	if (irq != AUTO_ASSIGN)
 		IO_APIC_VECTOR(irq) = vector;
 
-	spin_unlock(&vector_lock);
+	spin_unlock_irqrestore(&vector_lock, flags);
 
 	return vector;
 }
diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index 38a3ff30bde1..519cd4e6f9e7 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -836,14 +836,15 @@ u8 irq_vector[NR_IRQ_VECTORS] __read_mostly = { FIRST_DEVICE_VECTOR , 0 };
 int assign_irq_vector(int irq)
 {
 	static int current_vector = FIRST_DEVICE_VECTOR, offset = 0;
+	unsigned long flags;
 	int vector;
 
 	BUG_ON(irq != AUTO_ASSIGN && (unsigned)irq >= NR_IRQ_VECTORS);
 
-	spin_lock(&vector_lock);
+	spin_lock_irqsave(&vector_lock, flags);
 
 	if (irq != AUTO_ASSIGN && IO_APIC_VECTOR(irq) > 0) {
-		spin_unlock(&vector_lock);
+		spin_unlock_irqrestore(&vector_lock, flags);
 		return IO_APIC_VECTOR(irq);
 	}
 next:
@@ -862,7 +863,7 @@ next:
 	if (irq != AUTO_ASSIGN)
 		IO_APIC_VECTOR(irq) = vector;
 
-	spin_unlock(&vector_lock);
+	spin_unlock_irqrestore(&vector_lock, flags);
 
 	return vector;
 }