'Twas brillig, and Colin Walters at 20/07/13 23:50 did gyre and gimble: > So OSTree sets up systemd inside a chroot - /usr is a read-only bind > mount, and /var is a bind mount outside the root to a shared location. > Furthermore, /sysroot points to the real root. > > Since last time we discussed this: > http://lists.freedesktop.org/archives/systemd-devel/2012-September/006668.html > I now use this service inside dracut: > https://git.gnome.org/browse/ostree/tree/src/dracut/ostree-prepare-root.service > Which executes: > https://git.gnome.org/browse/ostree/tree/src/switchroot/ostree-prepare-root.c > > Then finally we do dracut's normal systemctl switch-root, and everything > continues as normal. I haven't had to patch the systemd codebase at all > for this. > > The problem is that on shutdown, systemd will synthesize usr.mount and > var.mount from /proc/self/mountinfo, but it can't really unmount them > until the same point as the rootfs. Because these units fail to > unmount, the normal shutdown process wedges. > > I can shutdown fine with systemctl --force poweroff, but then I don't > get plymouth integration etc. > > One way to fix this might be to somehow tell systemd to just ignore > these mount points during shutdown. Or possibly, switch back to the > initramfs and unmount them from there. > > The ugly thing about switching back to the initramfs is that it requires > unpacking it from the cpio blob again, which requires /boot to be > mounted, only to run a few unmount syscalls, and then finally power off. > > But if there was a way to tell systemd to just ignore the mounts, then > we'd drop into the final poweroff SIGTERM/SIGKILL/umount spree like > sysvinit did, and things would work. > > Anyone else doing bind mount tricks like this?
Interestingly, I asked something similar a while back. See the thread: "x-initrd.mount + shutdown umount logic question" http://thread.gmane.org/gmane.comp.sysutils.systemd.devel/11210 In my case it was pretty much a cosmetic issue but you want a harder exclusion I think... Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited http://www.tribalogic.net/ Open Source: Mageia Contributor http://www.mageia.org/ PulseAudio Hacker http://www.pulseaudio.org/ Trac Hacker http://trac.edgewall.org/ _______________________________________________ systemd-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/systemd-devel
