diff --git a/hw/openpic.c b/hw/openpic.c
index cf89f23192..f7d5583da5 100644
--- a/hw/openpic.c
+++ b/hw/openpic.c
@@ -128,7 +128,7 @@ enum {
 #define MPIC_MSI_REG_START        0x11C00
 #define MPIC_MSI_REG_SIZE         0x100
 #define MPIC_CPU_REG_START        0x20000
-#define MPIC_CPU_REG_SIZE         0x100
+#define MPIC_CPU_REG_SIZE         0x100 + ((MAX_CPU - 1) * 0x1000)
 
 enum mpic_ide_bits {
     IDR_EP     = 0,