How are you?
I just have a small question.
Is it possible to build a firmware with LEDE Stable but just upgrade the kernel and use instead Kernel 4.4 with 4.9?
But the rest is the same?
Is it possible and if so and it works I can set it to build the firmware with the 4.9?
If you want kernel 4.9, just go with current snapshots.
While nothing is impossible, the lede-17.01 branch doesn't have any kind of support for kernel 4.9, neither generic patches nor target specific ones. Backporting those would be quite some work and you'd probably miss quite a few essential albeit not obviously directly kernel related -but very much affected by it- changes, making this a much riskier endeavour than simply going with the master branch.
but the snapshots are not stable, isn't it?
That depends on your definition of stable.
It's not labelled as stable, nor has it gotten the amount of testing as a stable release (less the stable branch) has gotten -and there certainly may be occassions where the master branch is broken- but it's not intentionally unstable either. Knowing how to recover from a potential bad flash (many routers do have quite reliable tftp based recovery mechanisms) would be a good idea though, not just for running snapshots. You do need to be aware that snapshots don't have luci preinstalled, so if you need it, you need to get familiar with installing it from cli.
However there are quite some users running and updating master snapshots semi-regularly and snapshots definately get a ton more testing than your potential locally hacked up 17.01.x+kernel_4.9, where you'd be the sole and only developer and guinea pig.
And the 17.01.4 with 200+ kernel patches hacked by you for bump from 4.4 to 4.9 is stable?
Openwrt/LEDE has hundreds of rather low-level patches for the kernel, a Linux major version bump is a rather major task. There have been troubles with several earlier bumps. ar71xx was difficult to bump from 4.1 to 4.4, while ipq806x had real trouble with 4.4 to 4.9. (Those are the two targets that I am familiar with, and both of those have had trouble with recent kernel bumps...
That is just the reason why the "stable" is frozen to a kernel major version, 17.01.x is built with Linux 4.4. The next stable release 18.x will likely be based on 4.9.
ok , i guess I keep the stable 4.4 kernel... thanks!