The documentation suggests that the mount point (i.e. the directory
where the device is mounted) is removed when the device vanishes.
However only stopping of the automount unit is implemented.
So adapt the documentation to reality.
The /usr/lib/extensions/ location for systemd-sysext images is not
supported anymore. In https://github.com/systemd/systemd/pull/26013
systemd-confext images got introduced and we can list its path under
/usr instead.
This allows unprivileged validation of DDIs. Only superficial structure,
i.e. not mounting or so. This becomes particularly handy in the
integration tests, and to validate image policies.
The description was split — part was under ExecStart= and part in "Command lines".
Now the whole generic part is moved to the separate section, and under ExecStart=
only the stuff that is specific to that option is described.
This just moves the text and removes some repetitions.
We use ConditionControlGroupController=v2 in systemd-oomd.service, and also
this condition makes sense in general, so it should be documented.
This reverts a part of 6d48c7cf73.
Deprecated commandline options and v1 controller names were removed from
the description.
Follow-up for #26902 and #26971
Let's always calculate the next restart interval
since that's more useful.
For that, we add 1 to s->n_restarts unconditionally,
and change RestartUSecCurrent property to RestartUSecNext.
sysexts are meant to extend /usr. All extension images and directories are opened and merged in a
single, read-only overlayfs layer, mounted on /usr.
So far, we had fallback storage directories in /usr/lib/extensions and /usr/local/lib/extensions.
This is problematic for three reasons.
Firstly, technically, for directory-based extensions the kernel will reject
creating such an overlay, as there is a recursion problem. It actively
validates that a lowerdir is not a child of another lowerdir, and fails with
-ELOOP if it is. So having a sysext /usr/lib/extensions/myextdir/ would result
in an overlayfs config lowerdir=/usr/lib/extensions/myextdir/usr/:/usr which is
not allowed, as indicated by Christian the kernel performs this check:
/*
* Check if this layer root is a descendant of:
* - another layer of this overlayfs instance
* - upper/work dir of any overlayfs instance
*/
<...>
/* Walk back ancestors to root (inclusive) looking for traps */
while (!err && parent != next) {
if (is_lower && ovl_lookup_trap_inode(sb, parent)) {
err = -ELOOP;
pr_err("overlapping %s path\n", name);
Secondly, there's a confusing aspect to this recursive storage. If you
have /usr/lib/extensions/myext.raw which contains /usr/lib/extensions/mynested.raw
'systemd-sysext merge' will only pick up the first one, but both will appear in
the merged root under /usr/lib/extensions/. So you have two extension images, both
appear in your merged filesystem, but only one is actually in use.
Finally, there's a conceptual aspect: the idea behind sysexts and hermetic /usr
is that the /usr tree is not modified locally, but owned by the vendor. Dropping
extensions in /usr thus goes contrary to this foundational concept.
Unit names can be 255 characters long, not 256.
We first say "name prefix" and then continue with "unit prefix".
Confusing. Couldn't figure out which term is better hence settled on
"unit name prefix".
sysext DDI cannot carry an os-release file, but have to carry
an extension-release file. But so far, this was only used to
match the sysext DDI with the base DDI/rootdir. It is also
useful to describe the sysext DDI itself, just like we do in
os-release.
So document that the same fields used in os-release can also
be added to an extension-release, with the 'SYSEXT_' prefix,
and in that case they are understood to define the sysext DDI
itself, rather than for matching purposes.
interval between restarts
RestartSteps= accepts a positive integer as the number of steps
to take to increase the interval between auto-restarts from
RestartSec= to RestartSecMax=, or 0 to disable it.
Closes#6129
Define $KERNEL_INSTALL_UKI_GENERATOR in case one wants it to be different from $KERNEL_INSTALL_INITRD_GENERATOR. This can be useful if one wants to use mkinitcpio / Dracut to generate the initrd, but without creating the UKI so this can be left for e.g. ukify or something else. Right now these initrd generators will read /etc/kernel/install.conf and generate the UKI
Let's allow configuring tty term and size using kernel cmdline arguments
so that when running in a VM we can communicate the terminal TERM and size
from the host via SMBIOS extra kernel cmdline arguments.
Uwe Kleine-König
Zbigniew Jędrzejewski-Szmek
Sorah Fukumori
Kai Lueke
maanyagoenka
Lennart Poettering
Yu Watanabe
Mike Yuan
Daan De Meyer
Luca Boccassi
Gertalitec
Frantisek Sumsal
Jan Janssen
Antonio Alvarez Feijoo
Addison Snelling