diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index 9be0cb80ad..21351ffffc 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -67,7 +67,7 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
     prepare_cpu_entries(sclp, read_info->entries, &cpu_count);
     read_info->entries_cpu = cpu_to_be16(cpu_count);
     read_info->offset_cpu = cpu_to_be16(offsetof(ReadInfo, entries));
-    read_info->highest_cpu = cpu_to_be16(max_cpus);
+    read_info->highest_cpu = cpu_to_be16(max_cpus - 1);
 
     read_info->ibc_val = cpu_to_be32(s390_get_ibc_val());