diff --git a/xen/common/grant_table.c b/xen/common/grant_table.c
index 107b000..337e17a 100644
--- a/xen/common/grant_table.c
+++ b/xen/common/grant_table.c
@@ -1852,10 +1852,9 @@ __acquire_grant_for_copy(
         PIN_FAIL(unlock_out, GNTST_general_error,
                  "remote grant table not ready\n");
 
-    if ( unlikely(gref >= nr_grant_entries(rgt)) )
-        PIN_FAIL(unlock_out, GNTST_bad_gntref,
-                 "Bad grant reference %ld\n", gref);
-
+    if ( unlikely(gref >= nr_grant_entries(rgt)) ){
+        PIN_FAIL(unlock_out, GNTST_bad_gntref, "Bad grant reference %ld gt_version:%d ldom:%d readonly:%d allow_transitive:%d\n", gref, rgt->gt_version, ldom, readonly, allow_transitive);
+    }
     act = &active_entry(rgt, gref);
     shah = shared_entry_header(rgt, gref);
     if ( rgt->gt_version == 1 )
@@ -2071,8 +2070,10 @@ __gnttab_copy(
                                       current->domain->domain_id, 1,
                                       &s_frame, &s_pg,
                                       &source_off, &source_len, 1);
-        if ( rc != GNTST_okay )
-            goto error_out;
+        if ( rc != GNTST_okay ){
+            gdprintk(XENLOG_WARNING, "acquire_grant_for_copy failed .. src_is_gref rc:%d source.domid:%d dest.domid:%d s_frame:%ld source_off:%u source_len:%u op->source.offset:%d op->len:%d\n", rc, op->source.domid, op->dest.domid, s_frame, source_off, source_len, op->source.offset, op->len);
+	    goto error_out;
+	}
         have_s_grant = 1;
         if ( op->source.offset < source_off ||
              op->len > source_len )
@@ -2095,8 +2096,10 @@ __gnttab_copy(
         rc = __acquire_grant_for_copy(dd, op->dest.u.ref,
                                       current->domain->domain_id, 0,
                                       &d_frame, &d_pg, &dest_off, &dest_len, 1);
-        if ( rc != GNTST_okay )
-            goto error_out;
+        if ( rc != GNTST_okay ){
+            gdprintk(XENLOG_WARNING, "acquire_grant_for_copy failed .. dest_is_gref rc:%d source.domid:%d dest.domid:%d s_frame:%ld source_off:%u source_len:%u op->source.offset:%d op->len:%d\n", rc, op->source.domid, op->dest.domid, s_frame, dest_off, dest_len, op->dest.offset, op->len);
+	    goto error_out;
+	}
         have_d_grant = 1;
         if ( op->dest.offset < dest_off ||
              op->len > dest_len )