diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index ee01c5e66b..6febbabcaa 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -17,6 +17,7 @@
  * GNU GPL, version 2 or (at your option) any later version.
  */
 #include "qemu/osdep.h"
+#include "qemu/units.h"
 #include "qapi/error.h"
 #include "qemu/cutils.h"
 #include "hw/hw.h"
@@ -1301,7 +1302,7 @@ static void ivshmem_realize(PCIDevice *dev, Error **errp)
     }
 
     if (s->sizearg == NULL) {
-        s->legacy_size = 4 << 20; /* 4 MB default */
+        s->legacy_size = 4 * MiB; /* 4 MB default */
     } else {
         int ret;
         uint64_t size;