Basically, one of the issues that's plagued OEMs in the past is the fact that each SoC vendor (e.g. Qualcomm, Samsung, ARM) would not only have a kernel for each SoC, but each OEM device using that SoC would be another branch on that SoC-specific repository. This would then be compounded by the OEMs having their own kernel repositories that pull from the device-specific branches of a SoC repository, and bug fixes from OEMs would have to trickle back upstream to the vendor repository before making them back to other device-specific kernels.
The new proposed model would see a single kernel soruce for a given SoC, and device-specific changes would come in the form of kernel modules, config overrides, and device tree overlays. They are also strongly recommending SoC changes to the kernel be upstreamed to mainline Linux, which would greatly ease porting to newer kernels in the future.
Recommendations are just that, advices that might be followed, or not.
It isn't the first time that Google does recommendations to OEMs.
They also did recommendations for security updates. An advice that OEMs only follow for the customers that paid the big bucks for the flagship devices.
So unless they actually provide requirements instead of recommendations, nothing will change for consumers.
For example, something I was excited to see is in the updated documentation on source.android.com with regards to how they recommend developing kernel branches alongside devices: https://source.android.com/devices/architecture/kernel/modul...
Basically, one of the issues that's plagued OEMs in the past is the fact that each SoC vendor (e.g. Qualcomm, Samsung, ARM) would not only have a kernel for each SoC, but each OEM device using that SoC would be another branch on that SoC-specific repository. This would then be compounded by the OEMs having their own kernel repositories that pull from the device-specific branches of a SoC repository, and bug fixes from OEMs would have to trickle back upstream to the vendor repository before making them back to other device-specific kernels.
The new proposed model would see a single kernel soruce for a given SoC, and device-specific changes would come in the form of kernel modules, config overrides, and device tree overlays. They are also strongly recommending SoC changes to the kernel be upstreamed to mainline Linux, which would greatly ease porting to newer kernels in the future.