[pmjordan]

In addition to the sensible question of whether Google even would need to link against any GPL code raised by other commenters, there's also the question of whether the GPL would even make any sense for a kext, considering the kext needs to include Apple's header files (largely APSL-licensed) and link against macOS's kernel. (binary-only proprietary fork of the open source xnu source dump)

(I've licensed my own FOSS kext code as LGPL - either way, the copyleft aspect wouldn't affect any userland code using the kext as it'd be running in a different process. And AGPL doesn't change anything in this context either as far as I'm aware as its additional provisions are only relevant for code running on systems not under the user's control, and again if you're not linking against it, your code isn't a derived work.)