diff --git a/filesystem/filesystem.go b/filesystem/filesystem.go
index 0ce31b2..9f2b239 100644
--- a/filesystem/filesystem.go
+++ b/filesystem/filesystem.go
@@ -131,7 +131,7 @@
 	// The index used to prevent rollback of the image. Only used if use_avb is true.
 	Rollback_index *int64
 
-	// Rollback index location of this image. Must be 0, 1, 2, etc.
+	// Rollback index location of this image. Must be 1, 2, 3, etc.
 	Rollback_index_location *int64
 
 	// Name of the partition stored in vbmeta desc. Defaults to the name of this module.