diff --git a/arch/s390/include/asm/mem_detect.h b/arch/s390/include/asm/mem_detect.h
index 08798ddf5143..decd8c4cb799 100644
--- a/arch/s390/include/asm/mem_detect.h
+++ b/arch/s390/include/asm/mem_detect.h
@@ -40,8 +40,11 @@ void add_mem_detect_block(u64 start, u64 end);
 static inline int __get_mem_detect_block(u32 n, unsigned long *start,
 					 unsigned long *end)
 {
-	if (n >= mem_detect.count)
+	if (n >= mem_detect.count) {
+		*start = 0;
+		*end = 0;
 		return -1;
+	}
 
 	if (n < MEM_INLINED_ENTRIES) {
 		*start = (unsigned long)mem_detect.entries[n].start;