Comment by Aurornis

Given that Raspberry Pi hasn’t actually been well supported by mainline Linux and that the Raspberry Pi foundation hasn’t put a lot of effort into upstreaming things, I don’t think it’s actually a big deal. People don’t care where their kernel comes from as long as it works.

I am surprised by all of the comments here that assume Raspberry Pi has great upstream support. It’s amazing that people just assumed their boards were working great with upstream kernels. Raspberry Pi has a history of doing nonstandard things that serve their community but are actually a little bit quirky when it comes to normal embedded Linux.