systemd acceptance, packaging guidelines (was Re: systemd and changes)

[Lennart Poettering]

On Wed, 25.08.10 03:03, Miloslav Trmač (mitr at volny.cz) wrote:

> > > > > If the libraries or binaries used by systemd are replaced during runtime,
> > > > > and it is not re-executed on shutdown, the filesystem will have busy inodes
> > > > > on shutdown. (If you'd like to take the filesystem semantics up with the
> > > > > kernel, feel free to tilt at that windmill.)
> <snip> 
> > Well, what me still puzzles is this: the reexec is done asynchronously,
> > via signals. Shouldn't this be done synchronously at least to make
> > sure the daemon really is reexec'ed when we try to remount r/o?
>
> The traditional solution is to reexec not on shutdown, but immediately
> after init upgrade (which also frees the inodes early); this can still
> race with shutdown in theory, but is probably good enough in practice.

Well, while reexecing on package upgrades might kinda help fix the issue
I think it doesn't really scale, because you'd have to reexec systemd
when any of the libs it uses is upgraded, i.e. glibc, audit, selinux,
tcpwrap, pam, libcap.

So I guess there's isn't really any other option then reexecing init in
some way on shutdown.

Lennart

-- 
Lennart Poettering - Red Hat, Inc.