diff --git a/include/tests_boot_services b/include/tests_boot_services
index 19dc2fb1..33083be5 100644
--- a/include/tests_boot_services
+++ b/include/tests_boot_services
@@ -45,7 +45,7 @@
         fi
 
         # GRUB2 configuration file
-        if [ -f /boot/grub/grub.cfg -o /boot/grub2/grub.cfg ]; then
+        if [ -f /boot/grub/grub.cfg -o -f /boot/grub2/grub.cfg ]; then
             FOUND=1
             BOOT_LOADER="GRUB2"
             BOOT_LOADER_FOUND=1