diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 3c2855c3d6df..2dc081654f76 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -384,8 +384,12 @@ void startup_kernel(void)
 
 	/* vmlinux decompression is done, shrink reserved low memory */
 	physmem_reserve(RR_DECOMPRESSOR, 0, (unsigned long)_decompressor_end);
-	if (kaslr_enabled())
-		amode31_lma = randomize_within_range(vmlinux.amode31_size, PAGE_SIZE, 0, SZ_2G);
+	if (kaslr_enabled()) {
+		unsigned long amode31_min;
+
+		amode31_min = (unsigned long)_decompressor_end;
+		amode31_lma = randomize_within_range(vmlinux.amode31_size, PAGE_SIZE, amode31_min, SZ_2G);
+	}
 	amode31_lma = amode31_lma ?: vmlinux.default_lma - vmlinux.amode31_size;
 	physmem_reserve(RR_AMODE31, amode31_lma, vmlinux.amode31_size);