diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 2cc4b30..b4a1ab2 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -59,6 +59,8 @@
 #include <acpi/acpi_drivers.h>
 #include <acpi/processor.h>
 
+#define PREFIX "ACPI: "
+
 #define ACPI_PROCESSOR_CLASS		"processor"
 #define ACPI_PROCESSOR_DEVICE_NAME	"Processor"
 #define ACPI_PROCESSOR_FILE_INFO	"info"