diff --git a/roles/base/tasks/main.yml b/roles/base/tasks/main.yml
index d15898f1c3..c0a410b318 100644
--- a/roles/base/tasks/main.yml
+++ b/roles/base/tasks/main.yml
@@ -389,7 +389,7 @@
 #
 - name: Blacklist cdc_ether module
   copy: src=blacklist-cdc_ether.conf dest=/etc/modprobe.d/blacklist-cdc_ether.conf
-  when: ansible_virtualization_role == 'host'
+  when: ansible_virtualization_role is defined and ansible_virtualization_role == 'host'
   tags:
   - config
   - base