Other than 2 typos (inline). Looks good. Let's give it a day if somebody wants to object, then I'll commit it
movq %rax, %rsp
+ /*
+ * Here is grub_relocator64_efi_start() entry point.
+ * Following code is shared between grub_relocator64_efi_start()
+ * and grub_relocator64_start().
+ *
+ * Think twice before changing anything below!!!
+ */
+ /* Here grub_relocator64_efi_start() ends. Ufff... */
+VARIABLE(grub_relocator64_efi_end)
+