Linux stable vs RT stable and RT dev

["Mills, William" <wmills@ti.com>]

Hello,

I am trying to understand the policy WRT the RT stable branches and the Linux stable releases.
It appears not every Linux stable gets its own RT stable. [1]

What is the goal?  
	Not getting behind by more than X weeks?
	Only change when RT series needs to be updated?
What is the expected consumer model?:
	Use only the version published by the maintainer
	Merge in upstream point release themselves between rt-stable releases
How is the policy different for rt-dev vs rt-stable?

I know Steven wrote up a stable RT maintainer's howto but I did not find it.  Can I get a pointer?
I did find Steven's slides from 2106[2] and skimmed them.

[1] https://cdn.kernel.org/pub/linux/kernel/projects/rt/4.4/older/
[2] https://wiki.linuxfoundation.org/_media/realtime/events/rt-summit2016/how-much-stable-do-we-need_steven-rostedt.pdf

Long version / background
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TI publishes 3 variants of our kernel for customers:
	Base + TI + [Linaro LSK]
	Base + TI + RT
	Base + TI + Android Common

All this is based on the latest GKH LTS and there is maintenance of last years LTS

(Yes we understand this is all very simple if the TI set is nil.  We have never achieved that to date.  In the very least it is backports from tip to latest LTS.  In reality it is more.)

Right now Base above is always the very latest stable from GKH LTS.  It is auto merged as soon as it is published and picked up by our nightly builds.   Any merge conflict in any of the variants stops auto merge progress.

In this structure we tend to be the first to merge RT with a new stable.  Most of the time this is OK but sometimes it is not.

Is it reasonable / expected for us to get ahead of you or should we arrange things to just wait?

I used 4.9 in this example but right now we are executing this on 4.14, 4.9, and (somewhat) 4.4.

Thanks,
Bill

---------------------------------------------------
William A. Mills
Chief Technologist, Open Source
Texas Instruments, Processors
20450 Century Blvd
Germantown MD, 20874
(work/mobile) +1-240-643-0836