diff -up acpica-unix2-20140424/source/include/platform/aclinux.h.s390x acpica-unix2-20140424/source/include/platform/aclinux.h
--- acpica-unix2-20140424/source/include/platform/aclinux.h.s390x	2014-06-06 21:58:18.000000000 +0200
+++ acpica-unix2-20140424/source/include/platform/aclinux.h	2014-06-06 21:58:32.000000000 +0200
@@ -134,7 +134,7 @@
 #define ACPI_CAST_PTHREAD_T(Pthread) ((ACPI_THREAD_ID) (Pthread))
 
 #if defined(__ia64__)    || defined(__x86_64__) ||\
-    defined(__aarch64__) || defined(__PPC64__)
+    defined(__aarch64__) || defined(__PPC64__) || defined(__s390x__)
 #define ACPI_MACHINE_WIDTH          64
 #define COMPILER_DEPENDENT_INT64    long
 #define COMPILER_DEPENDENT_UINT64   unsigned long