[systemd-devel] Question about relationship between systemd v219 and kernel version.

[Lennart Poettering]

On Tue, 07.04.15 17:41, Dimitri John Ledkov (dimitri.j.ledkov at intel.com) wrote:

> On 6 April 2015 at 01:12, Lennart Poettering <lennart at poettering.net> wrote:
> > On Mon, 06.04.15 06:17, 임창근 (ck21.im at samsung.com) wrote:
> >
> >> Hello EveryOne.
> >>
> >> I wonder that If I use kernel v3.4 with systemd v219, systemd-run function is work or not.
> >> Because My target have kernel v3.4 and systemd v216.
> >
> > Please check the README shipped in the tarball, it always lists the
> > minimal kernel version systemd requires. For 219 the minimal kernel
> > version is 3.7.
> 
> I was meant to ask a while back, would it be possible to have degraded
> systemd for lower kernels? Quite a few current Android-like phones
> will be stuck on 3.4 forever, e.g. those that are shipping SailfishOS
> / Ubuntu for Phones / etc. Thus support for 3.4 is desirable to be
> maintained, because of the Android phones.

The last time the kernel requirement was bumped because firmware
loading support was dropped from systemd. Kernel 3.7 gained support
for in-kernel loading. Supporting older kernels would hence mean
readding that code to udev, and that's just not going to happen...

If you don't need firmware loading I think there's a good chance that
systemd will just work on older kernels. YMMV. 

Check the git log of README to see the history how the kernel
requirement was bumped, and why.

Lennart

-- 
Lennart Poettering, Red Hat