This package is now deprecated. Do not use. Replace your packages with postcss-loader or [webpack-stylelint-loader] instead.
Stylelint does not do a good job of handling imported files, and stylelint-loader is a wrapper around stylelint, so it inherits all the bugs and issues of stylelint. You can use the stylelint-webpack-plugin to recursively lint all your stylesheets. See the stylelint-webpack-plugin for more details (and thanks to @vieron for providing the plugin).
I'm likely to be shutting down stylelint-loader in preference to the stylelint-webpack-plugin in the future.
I am no longer accepting contributions as this package is deprecated.