Xiaomi is an emerging smartphone manufacturer,known for selling it's high quality Smartphones at jaw dropping prices.
It's now an International Company rebranded itself as MI for the International Market.
It manufactured High end hardware ,they come preloaded with MIUI a custom fork of Android could term it as  best custom fork but nothing is perfect . MIUI has it's own cons it has bugs some apps get force closed .
And more over users needs choices,you cant just get stuck with just MIUI right .
Due to unavailability of kernel sources we third party developers couldn't build any custom aftermarket ROM's.
We  request Xiaomi to please release complete Kernel sources so we could build great aftermarket firmwares .
Xiaomi is currently voilating GPL because the Android Kernel which is just a linux Kernel is licensed under GPL .
You make Great Phones but locking down to MIUI doesn't let us (users) to get full potential of the hardware .
You claim you manufacture devices by hearing from your users,so why not listen to your users voices and release kernel sources .
Regards,
Xiaomi MI3 Users.