diff --git a/hw/loader.c b/hw/loader.c
index 415cdce534..7d64113e7f 100644
--- a/hw/loader.c
+++ b/hw/loader.c
@@ -103,7 +103,7 @@ ssize_t read_targphys(const char *name,
 
 /* return the size or -1 if error */
 int load_image_targphys(const char *filename,
-			target_phys_addr_t addr, int max_sz)
+                        target_phys_addr_t addr, uint64_t max_sz)
 {
     int size;
 
diff --git a/hw/loader.h b/hw/loader.h
index fbcaba9f0c..6da291e31f 100644
--- a/hw/loader.h
+++ b/hw/loader.h
@@ -4,7 +4,8 @@
 /* loader.c */
 int get_image_size(const char *filename);
 int load_image(const char *filename, uint8_t *addr); /* deprecated */
-int load_image_targphys(const char *filename, target_phys_addr_t, int max_sz);
+int load_image_targphys(const char *filename, target_phys_addr_t,
+                        uint64_t max_sz);
 int load_elf(const char *filename, uint64_t (*translate_fn)(void *, uint64_t),
              void *translate_opaque, uint64_t *pentry, uint64_t *lowaddr,
              uint64_t *highaddr, int big_endian, int elf_machine,