What do you talk about? Stuxnet eventually deploys the native infected code for non-Windows PLC device, Windows is just a carrier not the final target:
"the Stuxnet worm incorporates several sophisticated means of propagation with the goal of eventually reaching and infecting STEP 7 project files used to program the PLC devices.
For initial propagation purposes, the worm targets computers running the Windows operating systems. However, the PLC itself is not a Windows-based system but rather a proprietary machine-language device."
