diff --git a/mm/usercopy.c b/mm/usercopy.c
index e7b0cb49daa1bef5f57bc0c7496ba5dca3bc1534..bf4d57fefee1499f149d097ed3c174431dc67108 100644
--- a/mm/usercopy.c
+++ b/mm/usercopy.c
@@ -284,7 +284,10 @@ static bool enable_checks __initdata = true;
 
 static int __init parse_hardened_usercopy(char *str)
 {
-	return strtobool(str, &enable_checks);
+	if (strtobool(str, &enable_checks))
+		pr_warn("Invalid option string for hardened_usercopy: '%s'\n",
+			str);
+	return 1;
 }
 
 __setup("hardened_usercopy=", parse_hardened_usercopy);