Bug#1071462: installing/upgrading libc6 does not work in sbuild when systemd is installed as ischroot declines

[Helmut Grohne]

Hi Chris,

On Mon, May 20, 2024 at 01:02:32AM +0200, Chris Hofstaedtler wrote:
> "..., when using telinit from systemd-sysv"
> 
> It would seem like a reasonable assumption that systemd-sysv's
> telinit uses systemd-specific stuff, like SIGTERM.

That also is an interesting angle to it. sbuild didn't ask for
systemd-sysv to be installed. It was installed due to Build-Depends of
some package. A different package might depend on sysvinit-core where
telinit writes to /run/initctl. Other telinit may do different things.
Handling all of telinit internals in one pid1 does not seem reasonable
to me, so the consequence of this would be that you shouldn't install
telinit in a build chroot and we could file bugs about any package doing
so. A particular consequence of this would be that you couldn't use
libpam-systemd or dbus-user-session in transitive Build-Depends. We'd
render a significant number of packages bd-uninstallable.

On the other hand, you have exactly the same problems when switching
your pid1 implementation (where we urgently advise rebooting to avoid
these kind of problems). That said, a sysvinit-core telinit likely
wouldn't break a container's tini/dumb-init nor break a systemd running
as pid1.

Helmut