[11:24] <sub526> I'm having the 16.04 GA kernel 4.4.0-28-generic, here i'd like to understand the semantics of this versioning(Major\Minor\Patch etc)?
[11:28] <sub526> For GA kernel, is there any chance of jumping the version numbers during the 5 years support?
[11:35] <xnox> sub526, it's a 28th upload of v4.4 based kernel. for more details see changelog as to what fixes it includes; security patches; features backports; upstream point-release inclusions.
[11:37] <xnox> sub526, no, it will not jump. but there is an hwe rolling kernel that does get bumped every ~6 months with newer series kernel. so cosmic/d-/e-/f- kernels will be made available on bionic.
[11:37] <xnox> sub526, but if there are particular drivers or features to backport, it can be requested for consideration via bug reports.
[11:49] <sub526> xnox: I see a patch "sched/headers: Move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>" in later v4.10 kernel. We are having an out-of-tree drivers and using the ubuntu 16.04 GA kernel, with GA kernel is it possible to test drivers with the mentioned patch?
[11:51] <xnox> sub526, you can install bionic kernel on xenial; and it should have that change. But I don't think such a change would be uploaded into the v4.4 kernel, as that sounds like it would break things.
[11:52] <xnox> sub526, on xenial-updates has v4.13.0 based kernel already, and xenial-proposed has v4.15.0 one.
[11:52] <xnox> sub526, but that's linux-hwe kernel flavour, not the default linux-generic.
[11:53] <xnox> but yeah, install linux-hwe kernel; reboot; and it should provide you with the new major kernel.
[11:54] <xnox> sub526, out-of-tree drivers -> ideally you want out-of-tree drivers to work with both GA and hwe kernels, as people are free to install either.
[12:01] <sub526> xnox: Our org people prefers GA kernel over hwe because it is stable solution and will continue to get security updates for the whole of the 5 years support period. At the same time they want out-of-tree drivers support for newer kernels, i don't know what's the solution?
[12:06] <tomreyn> doing twice the work. ;-)
[12:08] <xnox> sub526, you can write out-of-tree driver that is as compatible with many versions of kernel. How is it installed? if you are using dkms, you can, apply patches on per-target-kernel-version-number basis such that you can tweak the include paths
[12:23] <sub526> xnox: We release source code tarball and it will be stored in the build server. From this .deb package gets created and kept in internal repository. During apt-get install this source code gets copied to the ubuntu machine and gets build. I’m yet to understand this complete process, it looks we are using dkms. Can you please shed some light on how to go about doing this?