So I've compiled some of the newer kernels that I cloned from the raspberrypi github page, 4.15.13, and 4.15.10, and I believe I even tried 4.16.x, I can't remember. I use the bcmrpi3_defconfig and everything usually goes pretty well. I have noticed however, that things like disabling wifi via overlay (dtoverlay=pi3-disable-wifi) doesn't work with any of the 4.15 or 4.16 kernels. I made sure to copy over the freshly compiled dtbs and dtbos into my boot and boot/overlays so everything was updated per the compiled kernel version but no dice.
If I go back to the 4.9.y branch, everything works. I'm just curious if maybe there is some work the rpi foundation does on the newer kernels to enable the overlay functions to work which is why I can't get them to work? Obviously there are other ways to disable the wifi/and/or bluetooth but I usually use the overlay option. I just wanted to be sure I wasn't missing something in my kernel configuration or doing something "wrong". I typically use the kernel released through the apt repo, but have recently started building newer kernels (mostly for my pi 3 b+) and playing around with aarch64 operating systems and kernels.
Any insight would be appreciated. I'm kind of at a loss as to why the dtbo overlays will not load on the newer kernels but function perfectly on the 4.9.y branch.