[arch-general] Gentoo udev fork w/o systemd

[Daniel Micay]

On Mon, Nov 19, 2012 at 7:07 PM, Kevin Chadwick <ma1l1ists at yahoo.co.uk> wrote:
> On Tue, 20 Nov 2012 00:54:31 +0100
> Tom Gundersen <teg at jklm.no> wrote:
>
>> Having read through their discussions, it seems that the main two
>> things they would like to change is to be able to build udev without
>> building systemd (this does of course not change the resulting code,
>> but saves time if you have to build everything locally) and to make
>> the dependency on kmod optional (this might make sense if you don't
>> have module support in your kernel, but I think the difference would
>> not be measurable in any way).
>
> Odd, my take was that the main goal was trying to bring back a
> separate /usr.
>
> I did post to the arch-general mailing a while back about why the FSF is
> wrong on there being no need for a seperate /usr and putting everything
> in there without static core binaries in a smaller root is less
> reliable. I now wonder if that is because it was broken anyway and
> lennart gave a seemingly reasonable justification that may reduce the
> complaints.
>
> The other reason I noted was less dependency on upstream decisions or
> breakages and this one may have been the debian list but keeping dbus
> off servers.

The issues with a separate /usr were internal gentoo ones. Their
initramfs tool is not yet capable of mounting it, and their libkmod
package installed files to /usr (which has since been changed). That's
also the reason they removed the libkmod and libblkid support, but
since the standalone tools like modprobe still link against those
libraries there was no actual change in dependencies - just a few
hundred extra processes spawned at boot. Note that they're rolling
back those changes now, and are just going to make them "optional"
dependencies instead (but they will still be required, you can just
fork processes instead of calling library APIs).

They also dropped the goal of "POSIX compatibility", and are just
aiming to reduce "gnu-isms" instead even if it means bringing back
race conditions.

Gentoo is still using udev v171, and lots of the people assumed that
they couldn't be using up-to-date udev versions without systemd as
init. However, Arch managed to do that without any trouble, so it's
another non-reason for the fork.

Also, please keep in mind that this is not (yet) an official Gentoo
project, it's just a project done by a Gentoo developer so he gets to
use their infrastructure. It is definitely not supported by all Gentoo
developers (Greg KH being one of the vocal opponents, along with
several other core developers).