diff --git a/qemu/tests/cfg/cluster_size_check.cfg b/qemu/tests/cfg/cluster_size_check.cfg
index 59f2017a731ff5f3b9f84490972fe68d8d576395..2026451fb15f58fb79b043e993e4763c25acf885 100644
--- a/qemu/tests/cfg/cluster_size_check.cfg
+++ b/qemu/tests/cfg/cluster_size_check.cfg
@@ -18,3 +18,5 @@
         - negative_testing:
             status_error = "yes"
             cluster_size_set = "0k 4M"
+            Host_RHEL.m6:
+                cluster_size_set = "4M"