diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c
index f2053cbe9b0c..9be83990cf15 100644
--- a/arch/x86/platform/pvh/enlighten.c
+++ b/arch/x86/platform/pvh/enlighten.c
@@ -78,7 +78,9 @@ static void __init init_pvh_bootparams(bool xen_guest)
 		struct hvm_modlist_entry *modaddr =
 			__va(pvh_start_info.modlist_paddr);
 		pvh_bootparams.hdr.ramdisk_image = modaddr->paddr;
+		pvh_bootparams.ext_ramdisk_image = modaddr->paddr >> 32;
 		pvh_bootparams.hdr.ramdisk_size = modaddr->size;
+		pvh_bootparams.ext_ramdisk_size = modaddr->size >> 32;
 	}
 
 	/*