This contains the "bootctl install" related work from the #38764 split
out, but also includes the preparatory work already split out into
#40446.
I'll rebase this PR once the prep work is merged.
This has a simple CI test already, and has docs
When a cgroup is selected for termination, send varlink messages
to hooks registered in `/run/systemd/oomd.prekill-hooks/`.
oomd waits up to `PreKillHookTimeoutSec=` seconds for response
before proceeding with the kill.
Previously, setting HibernateDelaySec= would disable ACPI battery trip
point (_BTP) alarms, forcing the system to rely solely on software
polling for battery checks. This could result in the battery draining
to 0% between polling intervals, causing data loss.
Now, when ACPI _BTP is available AND HibernateDelaySec= is set, both
mechanisms work together. The system will hibernate on whichever comes
first: low battery (instant hardware alarm) or the configured timeout.
This also properly respects HibernateOnACPower=no by resetting the
timer while on AC power, matching the documented behavior.
Fixes: https://github.com/systemd/systemd/issues/26498
When the extensions for the final system are already set up from the
initrd we should avoid disrupting the boot process with the remount
(which currently isn't atomic) and the daemon reload for
systemd-confext and systemd-sysext. Similarly, when sysupdate ran and
updated extensions it's best to avoid the remount and daemon reload if
no changes are found.
To do this, encode the current extension state in more detail than
before where only the names of the extensions where encoded in the
overlay mount. This can also be used to provide more details about the
extension origin in "systemd-sysext status (--json=)". During the
refresh add a check whether the old state matches the new state and in
this case skip the refresh unless the user provides a flag to always
refresh. Besides the extension name and the resolved path the best
method for identification is the verity hash but that is not available
for plain image files or directories. Therefore, also include data to
check for file/directory replacements. The creation/modification times
are not always real on reproducible images or extracted archive content.
The file handle together with the unique mount ID is the next best
identifier we can use when we have no verity hash. Fall back to an inode
when we get no handle. With the creation/modification time and the path
this should be good enough. Using a unique mount ID is important (with
a fallback to the regular non-unique mount ID) instead of st_dev because
st_dev gets reused too easily, e.g., by a loop device mount and the
mount ID helps to catch this. For the mount ID to be valid it has to be
resolved before we enter the new mount namespace. Thus, it gets provided
by the image dissect logic and handed over to the sysext subprocess
which runs in a new mount namespace.
Luckily, we can rule out online modification of directories or image
files because this is anyway not well supported with overlay mounts, so
we don't do a file checksum nor do we recurse into a directory to look
for the most recently touched files. But, as said, with the
always-refresh flag one can force a reload.
When the extensions for the final system are already set up from the
initrd we should avoid disrupting the boot process with the remount
(which currently isn't atomic) and the daemon reload for
systemd-confext and systemd-sysext. Similarly, when sysupdate ran and
updated extensions it's best to avoid the remount and daemon reload if
no changes are found.
To do this, encode the current extension state in more detail than
before where only the names of the extensions where encoded in the
overlay mount. This can also be used to provide more details about the
extension origin in "systemd-sysext status (--json=)". During the
refresh add a check whether the old state matches the new state and in
this case skip the refresh unless the user provides a flag to always
refresh. Besides the extension name and the resolved path the best
method for identification is the verity hash but that is not available
for plain image files or directories. Therefore, also include data to
check for file/directory replacements. The creation/modification times
are not always real on reproducible images or extracted archive content.
The file handle together with the unique mount ID is the next best
identifier we can use when we have no verity hash. Fall back to an inode
when we get no handle. With the creation/modification time and the path
this should be good enough. Using a unique mount ID is important (with
a fallback to the regular non-unique mount ID) instead of st_dev because
st_dev gets reused too easily, e.g., by a loop device mount and the
mount ID helps to catch this. For the mount ID to be valid it has to be
resolved before we enter the new mount namespace. Thus, it gets provided
by the image dissect logic and handed over to the sysext subprocess
which runs in a new mount namespace.
Luckily, we can rule out online modification of directories or image
files because this is anyway not well supported with overlay mounts, so
we don't do a file checksum nor do we recurse into a directory to look
for the most recently touched files. But, as said, with the
always-refresh flag one can force a reload.
This patch adds a `--ephemeral` option to vmspawn that will turn
on snapshot mode on the qemu disk passed via `--image` or the
directory passed via `--directory`. For disk images it uses the
native mechanism that qemu provides. For directories it (re)uses
the snapshot mechanism that nspawn is using, i.e. it will create
a btrfs snapshot if possible and if not falls back to a traditional
directory copy.
Commit 15b1c33 ("repart: Generate fstab and crypttab late") moved
fstab/crypttab generation to the late stage but this introduced a regression:
it may be necessary to include fstab and crypttab into the generated partition
(e.g. with CopyFiles=). This is incompatible with 'fixate-volume-key' option as
it is impossible to capture LUKS volume key before it gets created but all the
rest should work fine.
Generate crypttab twice: early and late to capture possible changes. There's no
need to do the same for fstab for now, so keep the status quo.
Follow-up for af718e0535
The commit changed the documentation, but the actual impl
was apparently not updated. And the documented behavior
feels a bit off. I think generally "auto"/true should
override $NO_COLOR.
Plus, the test for auto-24bit is at odds with the logic
we merged. I guess it was overlooked after applying
https://github.com/systemd/systemd/pull/40303#discussion_r2720450393
This does not yet support directory images properly
as systemd itself does not support unpriv directory
images properly yet.
The user profiles are a copy of the system profiles but without
DynamicUser=yes (can't be used by user managers) and without
ProtectHome=yes (this masks /home which breaks StateDirectory= which
is lcoated inside /home)
In order to make "freeze" attacks against the update logic harder let's
add the ability to encode a "Best Before" date into SHA256SUMS directory
listings: if the current time is already beyond that time, we'll ignore
the SHA256SUMS as "stale" and fail the upgrade. Or in other words: the
freeze attack will now result in a client-side error eventually, instead
of success state.
The best before data is encoded in an optional pseudo-file listed in SHA256SUMS:
any file named BEST-BEFORE-YYYY-MM-DD.
Add an option to generate the expected volume key hash for LUKS volumes
by systemd-repart
and put it to crypttab, make systemd-cryptsetup check it upon attaching.
The format of the hash
matches what's currently being measured to TPM2 PCR with
tpm2-measure-pcr=.
Closes#40123
The expected hash (SHA265 HMAC signature) uses the exact same algorithm which
is used to calculate sha256 PCR bank digest when 'tpm2-measure-pcr=' is used.
When attaching images generate a policy in the portable drop-in
that matches the partition types and content found while dissecting,
so that it can no longer be changed later without a reattach.
Main focus was to not introduce breaking change or duplicated argument.
The `--limit-messages=` option that is used under the `monitor` verb is
reused here. However, both `wait` and `monitor` have contradicting
default behaviors, so it's not the cleanest thing to do.
There was some post-commit discussion about the API in #33961, but the
final name adopted in #34928 wasn't that flexible either to fit nicely
here in the `wait` verbe.
Additionally, there wasn't consideration in #34555 for having uniform
behavrious, so we ended with `wait` verb and `--limit-messages=` option,
rather than `receive` verb with default of continuously receving signals
withtout exit so `--limit-messages=` make more sence and be expectable.
RootImageOptions=/ExtensionImages=/MountImages= all support custom
mount options, but mountfsd does not support it. Add varlink
parameters to allow callers to specify mount options so that
those directives can work as expected. Require additional privs via
polkit.
Allow configuring the menu timeout used by sd-boot by setting
`io.systemd.boot.timeout=<value>` as SMBIOS type 11 string.
This takes precedence over the setting from the config file
and the EFI var.
Useful for e.g. integration tests that want to control that
a generic image boots faster.
The systemd-vmspawn man page has a note that the `--notify-ready`
defaults to "true" and then says that this is unlike "systemd-vmspawn"
where it defaults to "false". This appears to be a copy/paste issue
and here we want "unlike systemd-nspawn".
Setting Restart=0 seems reasonable to have no delay on the first
restart, if you do not realize this is impossible with an exponential
restart. So explicitly mention that RestartSec must be set.
RootImageOptions=/ExtensionImages=/MountImages= all support
custom mount options, use the new mountfsd parameters to
configure them if they are specified.
This requires additioanl privileges via polkit due to security
implications of mount options, so document an example policy
that allows to use the nosuid mount option.
Currently mount options are handled in such a way that the first
definition for a given partition wins, and documented as such.
Change them so that they behave like other options, and the
last specified wins.
Applies to RootImageOptions=, MountImages= and ExtensionImages=.
Switch from a linked list to an array indexed by the partition
specifier to store them.
Transparent Hugepages (THP) is a Linux kernel feature that manages
memory using larger pages (2MB on x86, compared to the default 4KB).
The main goal is to improve memory management efficiency and system
performance, especially for memory-intensive applications.
However, it can cause drawbacks in some scenarios, such as memory
regression and latency spikes. THP policy is governed for the entire
system via /sys/kernel/mm/transparent_hugepage/enabled.
However, it can be overridden for individual workloads via prctl(2)
call.
MemoryTHP= is used to disable THPs at exec-invoke to stop
providing THPs for workloads where the drawbacks outweigh the advantages.
When set to "disable", MemoryTHP= disables THPs completely for the
process, irrespecitive of global THP controls.
When set to "madvise", MemoryTHP= disables THPs for the process except
when specifically madvised by the process with MADV_HUGEPAGE or MADV_COLLAPSE.
Lennart Poettering
Zbigniew Jędrzejewski-Szmek
Daan De Meyer
Matteo Croce
Alessandro Astone
gvenugo3
Lennart Poettering
Kai Lueke
Michael Vogt
Graham Reed
Vitaly Kuznetsov
Kai Lüke
Mike Yuan
Daniel Foster
Peter Oliver
Antonio Alvarez Feijoo
Daan De Meyer
Luca Boccassi
Yu Watanabe
zefr0x
Luca Boccassi
Michael Vogt
Zbigniew Jędrzejewski-Szmek
Christian Hesse
Matthijs Kooijman
Usama Arif