f19065c283
The services systemd-random-seed-save.service and systemd-update-utmp-shutdown.service from systemd 203 don't work, because they have a RequiresMountFor dependency on /var/lib and /var/log. Such a dependency produces a cycle, causing systemd to drop those services: Fixing conflicting jobs by deleting job poweroff.target/stop Deleting job systemd-poweroff.service/stop as dependency of job poweroff.target/stop Deleting job umount.target/stop as dependency of job systemd-poweroff.service/stop Deleting job -.mount/start as dependency of job umount.target/stop Deleting job systemd-random-seed-save.service/start as dependency of job -.mount/start Deleting job systemd-update-utmp-shutdown.service/start as dependency of job -.mount/start Dropping the RequiresMountFor doesn't work either, because then /var/... may have meen unmounted or remounted read-only. Upstream systemd fixes this by doing the actual work from an ExecStop action in an already-running service than conflicts with shutdown.target. So I backported that here. The main consequence is that wtmp shutdown records now get written properly. The main lesson: shutdown.target is useless for pulling in services during shutdown if they need to write anywhere.
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