--- a/servo/components/config/opts.rs
+++ b/servo/components/config/opts.rs
@@ -95,17 +95,17 @@ pub struct Opts {
     /// debugging invalidation.
     pub paint_flashing: bool,
 
     /// If set with --disable-text-aa, disable antialiasing on fonts. This is primarily useful for reftests
     /// where pixel perfect results are required when using fonts such as the Ahem
     /// font for layout tests.
     pub enable_text_antialiasing: bool,
 
-    /// If set with --enable-subpixel, use subpixel antialiasing for glyphs. In the future
+    /// If set with --disable-subpixel, use subpixel antialiasing for glyphs. In the future
     /// this will likely become the default, but for now it's opt-in while we work
     /// out any bugs and improve the implementation.
     pub enable_subpixel_text_antialiasing: bool,
 
     /// If set with --disable-canvas-aa, disable antialiasing on the HTML canvas element.
     /// Like --disable-text-aa, this is useful for reftests where pixel perfect results are required.
     pub enable_canvas_antialiasing: bool,
 
@@ -241,18 +241,18 @@ pub struct DebugOptions {
     pub help: bool,
 
     /// Bubble intrinsic widths separately like other engines.
     pub bubble_widths: bool,
 
     /// Disable antialiasing of rendered text.
     pub disable_text_aa: bool,
 
-    /// Enable subpixel antialiasing of rendered text.
-    pub enable_subpixel_aa: bool,
+    /// Disable subpixel antialiasing of rendered text.
+    pub disable_subpixel_aa: bool,
 
     /// Disable antialiasing of rendered text on the HTML canvas element.
     pub disable_canvas_aa: bool,
 
     /// Print the DOM after each restyle.
     pub dump_style_tree: bool,
 
     /// Dumps the rule tree.
@@ -344,17 +344,17 @@ pub struct DebugOptions {
 
 impl DebugOptions {
     pub fn extend(&mut self, debug_string: String) -> Result<(), String> {
         for option in debug_string.split(',') {
             match option {
                 "help" => self.help = true,
                 "bubble-widths" => self.bubble_widths = true,
                 "disable-text-aa" => self.disable_text_aa = true,
-                "enable-subpixel-aa" => self.enable_subpixel_aa = true,
+                "disable-subpixel-aa" => self.disable_subpixel_aa = true,
                 "disable-canvas-aa" => self.disable_text_aa = true,
                 "dump-style-tree" => self.dump_style_tree = true,
                 "dump-rule-tree" => self.dump_rule_tree = true,
                 "dump-flow-tree" => self.dump_flow_tree = true,
                 "dump-display-list" => self.dump_display_list = true,
                 "dump-display-list-json" => self.dump_display_list_json = true,
                 "dump-layer-tree" => self.dump_layer_tree = true,
                 "relayout-event" => self.relayout_event = true,
@@ -823,17 +823,17 @@ pub fn from_cmdline_args(args: &[String]
         sandbox: opt_match.opt_present("S"),
         random_pipeline_closure_probability: random_pipeline_closure_probability,
         random_pipeline_closure_seed: random_pipeline_closure_seed,
         show_debug_fragment_borders: debug_options.show_fragment_borders,
         show_debug_parallel_paint: debug_options.show_parallel_paint,
         show_debug_parallel_layout: debug_options.show_parallel_layout,
         paint_flashing: debug_options.paint_flashing,
         enable_text_antialiasing: !debug_options.disable_text_aa,
-        enable_subpixel_text_antialiasing: debug_options.enable_subpixel_aa,
+        enable_subpixel_text_antialiasing: !debug_options.disable_subpixel_aa,
         enable_canvas_antialiasing: !debug_options.disable_canvas_aa,
         dump_style_tree: debug_options.dump_style_tree,
         dump_rule_tree: debug_options.dump_rule_tree,
         dump_flow_tree: debug_options.dump_flow_tree,
         dump_display_list: debug_options.dump_display_list,
         dump_display_list_json: debug_options.dump_display_list_json,
         dump_layer_tree: debug_options.dump_layer_tree,
         relayout_event: debug_options.relayout_event,