People don't want you to break their code.
What an uninformed take.
The Linux kernel has a strict "don't break userspace" policy, because they know that userspace is not released in lock step with the kernel. Having this policy is certainly a burden on them to get things right, but they've decided the trade offs make it worth it.
They have also chosen that the trade offs involved in having a stable driver API are not worth it.
> People don't want you to break their code.
Then maybe "people" (in this case device manufacturers who write crap drivers) should pony up the money and time to get their drivers mainlined so they don't have to worry about this problem. The Linux kernel team doesn't owe them anything.
They also know out of tree drivers are not released lock step with the kernel.
>They have also chosen that the trade offs involved in having a stable driver API are not worth it.
It sucks for driver developers to not have a stable API regardless if they think its worth it or not.
>should pony up the money and time to get their drivers mainlined so they don't have to worry about this problem.
They don't want to reveal their trade secrets.
>The Linux kernel team doesn't owe them anything.
Which is why Google ended up offering the stable API to driver developers.
Most linux kernel changes are limited enough so that updating a driver is not an issue, IFF you have the source code.
That is how a huge number of drivers are maintained in-tree, if they had to do major changes to all the drivers every time anything changes they wouldn't really get anything done.
Only if you don't have the source code is driver breakage an issue.
But Linux approach to proprietary drivers was always that there is no official support when there is no source code.