Index: /trunk/src/VBox/Devices/EFI/Firmware/OvmfPkg/OvmfPkgIa32.fdf
===================================================================
--- /trunk/src/VBox/Devices/EFI/Firmware/OvmfPkg/OvmfPkgIa32.fdf	(revision 58751)
+++ /trunk/src/VBox/Devices/EFI/Firmware/OvmfPkg/OvmfPkgIa32.fdf	(revision 58752)
@@ -79,5 +79,10 @@
 
 [FD.MEMFD]
-BaseAddress   = 0x800000
+!ifndef $(VBOX)
+  BaseAddress   = 0x800000
+!else
+  # Need to relocate this or it interferes with certain OS X bootloaders breaking OS X guests
+  BaseAddress   = 0x2000000
+!endif
 Size          = 0x900000
 ErasePolarity = 1
Index: /trunk/src/VBox/Devices/EFI/Firmware/OvmfPkg/OvmfPkgX64.fdf
===================================================================
--- /trunk/src/VBox/Devices/EFI/Firmware/OvmfPkg/OvmfPkgX64.fdf	(revision 58751)
+++ /trunk/src/VBox/Devices/EFI/Firmware/OvmfPkg/OvmfPkgX64.fdf	(revision 58752)
@@ -79,5 +79,10 @@
 
 [FD.MEMFD]
-BaseAddress   = 0x800000
+!ifndef $(VBOX)
+  BaseAddress   = 0x800000
+!else
+  # Need to relocate this or it interferes with certain OS X bootloaders breaking OS X guests
+  BaseAddress   = 0x2000000
+!endif
 Size          = 0x900000
 ErasePolarity = 1