The rootfs mounted read-write, so a slot ran with its own files open to
change, and the factory-slot mounts rode along on the release image.
Both images now carry the read-only-rootfs feature: the ro root line and
the rcS default, the volatile links made at rootfs time, a writable copy
of /var/lib at boot, a build failure for a post-install that needs the
machine, and the removal of shadow, base-passwd, update-rc.d and
update-alternatives.
What must last or change at run time is handled file by file:
- forgefirm-users renders the four account files from the record into
/run/forgefirm/accounts and bind-mounts each copy over its /etc file
(useradd and the rest are gone with shadow); a render writes through
the mount, and the image's own files apply until the first render.
- forgefirm-banner bind-mounts a copy of /etc/issue and writes the
address block through it.
- sshd keeps its host keys under /data/forgefirm/ssh, so the fingerprint
survives updates; both sshd configs carry the same HostKey lines.
- forgefirm-logging passes logrotate a state file under /var/run
(logrotate refuses to run without one).
- forgefirm-persist points the boot timestamp and the random seed at
/data/forgefirm.
The dev image appends the /factory slot mounts, without nofail (busybox
mount hands it to the kernel, which rejects it). The rootfs command
entries lose their semicolons: on scarthgap the value is the task's
vardeps, split on whitespace, so "name;" left the function body out of
the signature and a changed body did not remake the rootfs; with the
bodies tracked, the dev image's DATETIME string needs a vardepsexclude.
release.sh gains the read-only gate (root ro, no /factory line,
ROOTFS_READ_ONLY=yes, host keys on /data). image.health checks the
mounts, the account binds, the banner bind, the host keys and the
dev-only /factory mounts.
Proven on the bench reference (dev image 20260909140901): / ro, /data
rw, /var/lib a tmpfs copy, the four account files and /etc/issue bound
from tmpfs, the host keys in /data/forgefirm/ssh, no "Read-only file
system" line in any log; forgectrl.auth and commission.account-login (a
temporary account rendered, logged in over HTTPS and removed again),
kernel.latch-locked-idle and motion.liveness-probe PASS; logrotate runs
with the volatile state. forgetest unit tests 335 OK; both images build
clean, and debugfs on the built rootfs shows every setting above.
A read-only mount of an ext4 slot still replays its journal, which
writes to the partition the probe was not meant to touch. The probe
mounts with noload: the journal is left as it is and the slot's
content is read as it stands.
Acceptance: update.slots covers ffboot -l (covers map ffboot/**).
The inheritance walk skipped every record that was not a PASS on the
current fingerprint, so a FAIL or ERROR recorded after a PASS on the
same image was stepped over and the older PASS inherited into the next
campaign. The newest record on the fingerprint now decides: a PASS is
inherited, a FAIL or ERROR blocks it (reason failed-since), an ABORTED
run says nothing. Unit tests for all three orders.
ffboot, the tool that rewrites the boot environment on every install and
slot switch, was packaged from scripts/ outside every fingerprint. It
now lives in the recipe's files and the recipe inherits the manifest
class; the tree manifest tool fingerprints file components the same
way, and the update tests cover the component.
forgectrl.settings-bounds fell back to ui_units=mm, which the whitelist
refuses, so the always-required test failed on a fresh machine; the
fallback is metric.
-l inventories every bootable partition (SD, eMMC slots 1/2, legacy
p4) as machine-parsable key=value lines: firmware type
(forgefirm/factory), version, kernel presence, booted/next markers,
plus the saved-env selection - the shared probe for the installer and
the forgectrl update manager.
Boot switching now writes all four selection variables (mmcdev,
mmchwpart, mmcpart, mmcroot) in one fw_setenv -s transaction and
read-back verifies, falling back from the libubootenv script format
to the classic u-boot-tools format to per-variable writes - the same
script works on factory firmware and ForgeFIRM. mmchwpart was
previously never set and a mixed env could survive a mid-flip power
cut. Switch targets must pass a content probe (rootfs mounts, kernel
present) unless -f. -e picks the newest factory slot by probing,
excluding slots occupied by ForgeFIRM.
The new ffboot recipe installs it as /usr/sbin/ffboot with
/etc/fw_env.config (factory-identical redundant env layout at eMMC
0x80000/0x82000) - previously the image shipped fw_setenv with no
config. Added to forgefirm-image.
ScottW514