diff --git a/lib_generic/display_options.c b/lib_generic/display_options.c
index 5ddd94f..a52fa04 100644
--- a/lib_generic/display_options.c
+++ b/lib_generic/display_options.c
@@ -42,7 +42,7 @@
  * print sizes as "xxx kB", "xxx.y kB", "xxx MB" or "xxx.y MB" as needed;
  * allow for optional trailing string (like "\n")
  */
-void print_size (ulong size, const char *s)
+void print_size (phys_size_t size, const char *s)
 {
 	ulong m, n;
 	ulong d = 1 << 20;		/* 1 MB */