diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 0a6ff93229..45ff7db1e8 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -1798,6 +1798,13 @@ int xc_cpuid_set(xc_interface *xch,
                  const unsigned int *input,
                  const char **config,
                  char **config_transformed);
+
+/*
+ * Make adjustments to the CPUID settings for a domain.
+ *
+ * Either pass a full new @featureset (and @nr_features), or adjust individual
+ * features (@pae).
+ */
 int xc_cpuid_apply_policy(xc_interface *xch,
                           uint32_t domid,
                           const uint32_t *featureset,
diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c
index 5ced6d18b9..f045b03223 100644
--- a/tools/libxc/xc_cpuid_x86.c
+++ b/tools/libxc/xc_cpuid_x86.c
@@ -532,6 +532,11 @@ int xc_cpuid_apply_policy(xc_interface *xch, uint32_t domid,
 
         cpuid_featureset_to_policy(feat, p);
     }
+    else
+    {
+        if ( di.hvm )
+            p->basic.pae = pae;
+    }
 
     if ( !di.hvm )
     {
@@ -615,8 +620,6 @@ int xc_cpuid_apply_policy(xc_interface *xch, uint32_t domid,
             break;
         }
 
-        p->basic.pae = pae;
-
         /*
          * These settings are necessary to cause earlier HVM_PARAM_NESTEDHVM /
          * XEN_DOMCTL_disable_migrate settings to be reflected correctly in