--- old/src/hotspot/share/gc/g1/g1HeapVerifier.cpp	2017-11-29 16:41:17.964763409 +0100
+++ new/src/hotspot/share/gc/g1/g1HeapVerifier.cpp	2017-11-29 16:41:17.724753922 +0100
@@ -377,8 +377,10 @@
 };
 
 void G1HeapVerifier::parse_verification_type(const char* type) {
-  if (strcmp(type, "young") == 0) {
-    enable_verification_type(G1VerifyYoung);
+  if (strcmp(type, "young-only") == 0) {
+    enable_verification_type(G1VerifyYoungOnly);
+  } else if (strcmp(type, "initial-mark") == 0) {
+    enable_verification_type(G1VerifyInitialMark);
   } else if (strcmp(type, "mixed") == 0) {
     enable_verification_type(G1VerifyMixed);
   } else if (strcmp(type, "remark") == 0) {
@@ -388,7 +390,8 @@
   } else if (strcmp(type, "full") == 0) {
     enable_verification_type(G1VerifyFull);
   } else {
-    log_warning(gc, verify)("VerifyGCType: '%s' is unknown. Available types are: young, mixed, remark, cleanup and full", type);
+    log_warning(gc, verify)("VerifyGCType: '%s' is unknown. Available types are: "
+                            "young-only, initial-mark, mixed, remark, cleanup and full", type);
   }
 }