I'm reasonably confident that it is upstream: https://github.com/torvalds/linux/blob/master/drivers/android/binder.c https://github.com/torvalds/linux/blob/mast

I'm reasonably confident that it is upstream: https://github.com/torvalds/linux/blob/master/drivers/android/binder.c https://github.com/torvalds/linux/blob/master/drivers/androi... looks like the most obvious bit, though there are other pieces. (And now I'm curious why waydroid is maintaining their own dkms code separate from that; perhaps it's to better target a range of kernel versions?) I will agree that it's not generally actually built/used by distros.