diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index 9de25d4fd9112b37f95186dab6943162bd0fc8f5..9968f30cca3e187d28acf2d7631609c29cb1bcf6 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -185,6 +185,7 @@ static struct apic apic_flat =  {
 
 	.cpu_mask_to_apicid_and		= flat_cpu_mask_to_apicid_and,
 
+	.send_IPI			= default_send_IPI_single,
 	.send_IPI_mask			= flat_send_IPI_mask,
 	.send_IPI_mask_allbutself	= flat_send_IPI_mask_allbutself,
 	.send_IPI_allbutself		= flat_send_IPI_allbutself,
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 7694ae6c1199b370331e550601ac6a36d89933e9..f316e34abb42bef31fbf8948bb1cdd8c4491fcbe 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -105,6 +105,7 @@ static struct apic apic_default = {
 
 	.cpu_mask_to_apicid_and		= flat_cpu_mask_to_apicid_and,
 
+	.send_IPI			= default_send_IPI_single,
 	.send_IPI_mask			= default_send_IPI_mask_logical,
 	.send_IPI_mask_allbutself	= default_send_IPI_mask_allbutself_logical,
 	.send_IPI_allbutself		= default_send_IPI_allbutself,