What does Kernel 4.0 mean for Gentoo?

dalu · Guru Joined: 20 Jan 2003 Posts: 530

Does it mean anything at all?

Will the workflow change?
Will genkernel be obsolete, will it be extended, or will there be another tool?
Will "you" use kpatch or kGraft?

How does kpatch|kGraft work anyway?

How will it all work with OpenRC or systemd?

Anything else

mv · Watchman Joined: 20 Apr 2005 Posts: 6747

asturm · Developer Joined: 05 Apr 2007 Posts: 8935

Been using it for weeks, didn't notice a change. Except that a two year old regression was fixed for me.

dalu · Guru Joined: 20 Jan 2003 Posts: 530

But this live kernel patching is a big thing, right?

When you don't need to reboot a machine after a new kernel, that's a big deal, for me anyways.
And I wonder how I could take advantage of it.

Does that mean that I have to compile a new kernel or will there just be patches?
If it's just patches you wouldn't need to recompile the whole kernel again.
If not how do I put it to use?

Is "reboot" or "systemctl reboot" still the same?
Is there a new command?

Automated kernel and other security patches, depending on what packages/components are installed would serverly ease server maintenance.
Similarly upgrading a kernel, when you don't need to physically reboot any more would remove one annoyance from upgrading minor or even major kernel versions.

mv · Watchman Joined: 20 Apr 2005 Posts: 6747

AFAIK you cannot use this to upgrade to a new kernel. You can only use this for practically the same kernel when just a few patches in modules are backported.
Thus, for distributions which never change the kernel version but just backport security fixes, this may keep you a running server until the next major release.
Gentoo works dfifferently: Security fixes are not backported to older kernels, but you are expected to upgrade to the next kernel release (which usually never will consist only of backports in modules). Maybe some minor versions (4.0.0->4.0.1 etc) are possible, but that's probably not worth the effort.