--- a/python/mozbuild/mozbuild/vendor_rust.py
+++ b/python/mozbuild/mozbuild/vendor_rust.py
@@ -71,17 +71,17 @@ Please commit or stash these changes bef
             self.run_process(args=[cargo, 'install', 'cargo-vendor'])
         else:
             self.log(logging.DEBUG, 'cargo_vendor', {}, 'cargo-vendor already intalled')
         vendor_dir = mozpath.join(self.topsrcdir, 'third_party/rust')
         self.log(logging.INFO, 'rm_vendor_dir', {}, 'rm -rf %s' % vendor_dir)
         mozfile.remove(vendor_dir)
         # Once we require a new enough cargo to switch to workspaces, we can
         # just do this once on the workspace root crate.
-        for crate_root in ('toolkit/library/rust/',
-                           'toolkit/library/gtest/rust',
-                           'js/src'):
+        for (crate_root, lib) in (('toolkit/library/rust/', 'gkrust'),
+                                  ('toolkit/library/gtest/rust', 'gkrust-gtest'),
+                                  ('js/src', 'mozjs_sys')):
             path = mozpath.join(self.topsrcdir, crate_root)
-            self._run_command_in_srcdir(args=[cargo, 'generate-lockfile', '--manifest-path', mozpath.join(path, 'Cargo.toml')])
+            self._run_command_in_srcdir(args=[cargo, 'update', '--manifest-path', mozpath.join(path, 'Cargo.toml'), '-p', lib])
             self._run_command_in_srcdir(args=[cargo, 'vendor', '--sync', mozpath.join(path, 'Cargo.lock'), vendor_dir])
         #TODO: print stats on size of files added/removed, warn or error
         # when adding very large files (bug 1306078)
         self.repository.add_remove_files(vendor_dir)