[dispose13432]

The problem is that Linux's kernel interface isn't stable, so a module written for one kernel release won't work on another, and (AFAIK) they don't do major-minor releases (like PHP,Apache) where, say, the 4.0 kernel is stable and will stay stable for a few years. Rather, 4.1 could introduce braking changes as far as modules go.

And, unlike PCs, most phones don't have standard hardware, so someone kernel modules tend to be closed source and don't have "basic" mode.

As a result, to upgrade to a new Android release someone has to backport all new (kernel) features to old kernels.

[dmm]

If you upstream your drivers then the people who change interfaces also fix the modules that use those interfaces.

The problem is SoC manufacturers that don't want to put in the work to upstream drivers.

[dispose13432]

>The problem is SoC manufacturers that don't want to put in the work to upstream drivers.

They don't _open source_ their drivers.

[NoGravitas]

Many (most?) of them do open source their drivers. But even then, no one is willing to do the work to upstream them.

[yareally]

They sometimes release the driver blobs so you don't have to rip them off the device, but rarely have I heard of drivers being open sourced outside of a few scattered instances.

[dispose13432]

Really? Where is the full Samsung blobless kernel?