Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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+Bugfixes:
+
+* Many manager configuration settings that are only applicable to user
+  manager or system manager can be always set. It would be better to reject
+  them when parsing config.
+
+* Jun 01 09:43:02 krowka systemd[1]: Unit user@1000.service has alias user@.service.
+  Jun 01 09:43:02 krowka systemd[1]: Unit user@6.service has alias user@.service.
+  Jun 01 09:43:02 krowka systemd[1]: Unit user-runtime-dir@6.service has alias user-runtime-dir@.service.
+
+External:
+
+* Fedora: add an rpmlint check that verifies that all unit files in the RPM are listed in %systemd_post macros.
+
+* dbus:
+   - natively watch for dbus-*.service symlinks (PENDING)
+   - teach dbus to activate all services it finds in /etc/systemd/services/org-*.service
+
+* fedora: suggest auto-restart on failure, but not on success and not on coredump. also, ask people to think about changing the start limit logic. Also point people to RestartPreventExitStatus=, SuccessExitStatus=
+
+* neither pkexec nor sudo initialize environ[] from the PAM environment?
+
+* fedora: update policy to declare access mode and ownership of unit files to root:root 0644, and add an rpmlint check for it
+
+* register catalog database signature as file magic
+
+* zsh shell completion:
+  - <command> <verb> -<TAB> should complete options, but currently does not
+  - systemctl add-wants,add-requires
+  - systemctl reboot --boot-loader-entry=
+
+* systemctl status should know about 'systemd-analyze calendar ... --iterations='
+* If timer has just OnInactiveSec=..., it should fire after a specified time
+  after being started.
+
+* write blog stories about:
+  - hwdb: what belongs into it, lsusb
+  - enabling dbus services
+  - how to make changes to sysctl and sysfs attributes
+  - remote access
+  - how to pass throw-away units to systemd, or dynamically change properties of existing units
+  - testing with Harald's awesome test kit
+  - auto-restart
+  - how to develop against journal browsing APIs
+  - the journal HTTP iface
+  - non-cgroup resource management
+  - dynamic resource management with cgroups
+  - refreshed, longer missions statement
+  - calendar time events
+  - init=/bin/sh vs. "emergency" mode, vs. "rescue" mode, vs. "multi-user" mode, vs. "graphical" mode, and the debug shell
+  - how to create your own target
+  - instantiated apache, dovecot and so on
+  - hooking a script into various stages of shutdown/early boot
+
+Regularly:
+
+* look for close() vs. close_nointr() vs. close_nointr_nofail()
+
+* check for strerror(r) instead of strerror(-r)
+
+* pahole
+
+* set_put(), hashmap_put() return values check. i.e. == 0 does not free()!
+
+* use secure_getenv() instead of getenv() where appropriate
+
+* link up selected blog stories from man pages and unit files Documentation= fields
+
+Janitorial Clean-ups:
+
+* rework mount.c and swap.c to follow proper state enumeration/deserialization
+  semantics, like we do for device.c now
+
+* get rid of prefix_roota() and similar, only use chase() and related
+  calls instead.
+
+* get rid of basename() and replace by path_extract_filename()
+
+* Replace our fstype_is_network() with a call to libmount's mnt_fstype_is_netfs()?
+  Having two lists is not nice, but maybe it's now worth making a dependency on
+  libmount for something so trivial.
+
+* drop set_free_free() and switch things over from string_hash_ops to
+  string_hash_ops_free everywhere, so that destruction is implicit rather than
+  explicit. Similar, for other special hashmap/set/ordered_hashmap destructors.
+
+* generators sometimes apply C escaping and sometimes specifier escaping to
+  paths and similar strings they write out. Sometimes both. We should clean
+  this up, and should probably always apply both, i.e. introduce
+  unit_file_escape() or so, which applies both.
+
+* xopenat() should pin the parent dir of the inode it creates before doing its
+  thing, so that it can create, open, label somewhat atomically.
+
+Deprecations and removals:
+
+* Remove any support for booting without /usr pre-mounted in the initrd entirely.
+  Update INITRD_INTERFACE.md accordingly.
+
+* remove cgroups v1 support EOY 2023. As per
+  https://lists.freedesktop.org/archives/systemd-devel/2022-July/048120.html
+  and then rework cgroupsv2 support around fds, i.e. keep one fd per active
+  unit around, and always operate on that, instead of cgroup fs paths.
+
+* drop support for kernels that lack ambient capabilities support (i.e. make
+  4.3 new baseline). Then drop support for "!!" modifier for ExecStart= which
+  is only supported for such old kernels.
+
+* drop support for kernels lacking memfd_create() (i.e. make 3.17 new
+  baseline), then drop all pipe() based fallbacks.
+
+* drop support for getrandom()-less kernels. (GRND_INSECURE means once kernel
+  5.6 becomes our baseline). See
+  https://github.com/systemd/systemd/pull/24101#issuecomment-1193966468 for
+  details. Maybe before that: at taint-flags/warn about kernels that lack
+  getrandom()/environments where it is blocked.
+
+* drop support for LOOP_CONFIGURE-less loopback block devices, once kernel
+  baseline is 5.8.
+
+* drop fd_is_mount_point() fallback mess once we can rely on
+  STATX_ATTR_MOUNT_ROOT to exist i.e. kernel baseline 5.8
+
+* Remove /dev/mem ACPI FPDT parsing when /sys/firmware/acpi/fpdt is ubiquitous.
+  That requires distros to enable CONFIG_ACPI_FPDT, and have kernels v5.12 for
+  x86 and v6.2 for arm.
+
+* Once baseline is 4.13, remove support for INTERFACE_OLD= checks in "udevadm
+  trigger"'s waiting logic, since we can then rely on uuid-tagged uevents
+
+* remove remaining tpm1.2 support from sd-stub
+
+Features:
+
+* add a kernel cmdline switch (and cred?) for marking a system to be
+  "headless", in which case we never open /dev/console for reading, only for
+  writing. This would then mean: systemd-firstboot would process creds but not
+  ask interactively, getty would not be started and so on.
+
+* extend mime database with mime types for:
+  - journal files
+  - credential files
+  - hwdb files
+  - catalog files
+
+* cryptsetup: new crypttab option to auto-grow a luks device to its backing
+  partition size. new crypttab option to reencrypt a luks device with a new
+  volume key.
+
+* we probably should have some infrastructure to acquire sysexts with
+  drivers/firmware for local hardware automatically. Idea: reuse the modalias
+  logic of the kernel for this: make the main OS image install a hwdb file
+  that matches against local modalias strings, and adds properties to relevant
+  devices listing names of sysexts needed to support the hw. Then provide some
+  tool that goes through all devices and tries to acquire/download the
+  specified images.
+
+* repart + cryptsetup: support file systems that are encrypted and use verity
+  on top. Usecase: confexts that shall be signed by the admin but also be
+  confidential. Then, add a new --make-ddi=confext-encrypted for this.
+
+* tmpfiles: add new line type for moving files from some source dir to some
+  target dir. then use that to move sysexts/confexts and stuff from initrd
+  tmpfs to /run/, so that host can pick things up.
+
+* tiny varlink service that takes a fd passed in and serves it via http. Then
+  make use of that in networkd, and expose some EFI binary of choice for
+  DHCP/HTTP base EFI boot.
+
+* bootctl: add reboot-to-disk which takes a block device name, and
+  automatically sets things up so that system reboots into that device next.
+
+* maybe: in PID1, when we detect we run in an initrd, make superblock read-only
+  early on, but provide opt-out via kernel cmdline.
+
+* systemd-pcrextend:
+  - support measuring to nvindex with PCR update semantics ("fake PCRs")
+  - add api for "allocating" such an nvindex
+  - once we have that start measuring every sysext we apply, every confext,
+    every RootImage= we apply, every nspawn and so on. All in separate fake
+    PCRs.
+
+* vmspawn:
+  - enable hyperv extension by default (https://www.qemu.org/docs/master/system/i386/hyperv.html)
+  - register with machined
+  - run in scope unit when invoked from command line, and machined registration is off
+  - support --directory= via virtiofs
+  - sd_notify support
+  - --ephemeral support
+  - --read-only support
+  - automatically suspend/resume the VM if the host suspends. Use logind
+    suspend inhibitor to implement this. request clean suspend by generating
+    suspend key presses.
+  - support for "real" networking via "-n" and --network-bridge=
+  - automatically run service "at the side" for swtpm
+  - translate SIGTERM to clean ACPI shutdown event
+
+* systemd-pcrmachine should probably also measure the SMBIOS system UUID.
+
+* sd-boot: allow synthesizing additional type1 entries via SMBIOS vendor strings
+
+* storagetm:
+  - add USB mass storage device logic, so that all local disks are also exposed
+    as mass storage devices on systems that have a USB controller that can
+    operate in device mode
+  - add NVMe authentication
+
+* add support for activating nvme-oF devices at boot automatically via kernel
+  cmdline, and maybe even support a syntax such as
+  root=nvme:<trtype>:<traddr>:<trsvcid>:<nqn>:<partition> to boot directly from
+  nvme-oF
+
+* pcrlock:
+  - make signed PCR work together with pcrlock
+  - add kernel-install plugin that automatically creates UKI .pcrlock file when
+    UKI is installed, and removes it when it is removed again
+  - automatically install PE measurement of sd-boot on "bootctl install"
+  - write generated pcrlock signature files to the ESP as credential, one for
+    each installed OS & pick up generated pcrlock signature file in sd-stub,
+    pass it via initrd to OS
+  - pre-calc sysext + kernel cmdline measurements
+  - pre-calc cryptsetup root key measurement
+  - maybe make systemd-repart generate .pcrlock for old and new GPT header in
+    /run?
+  - Add support for more than 8 branches per PCR OR
+  - add "systemd-pcrlock lock-kernel-current" or so which synthesizes .pcrlock
+    policy from currently booted kernel/event log, to close gap for first boot
+    for pre-built images
+
+* add a new systemd-project@.service that is very similar to user@.service but
+  uses DynamicUser=1 and no PAMName= to invoke an unprivileged somewhat
+  light-weight service manager. Use HOME=/var/lib/systemd/projects/%i as home
+  dir. Similar for $XDG_RUNTIME_DIR. Start project@%i.target. Use LogField= to
+  add a field identifying the project.
+
+* logind: add a new dbus call Sleep() which automatically redirects to one of
+  Suspend(), Hibernate(), SuspendThenHibernate() depending on what is
+  available, and also subject to some local configuration in
+  logind.conf. Should default to SuspendThenHibernate() if available, and then
+  fallback to Suspend() and finally Hibernate() if not. Then expose this as
+  "systemctl sleep", and tell DEs to default to this.
+
+* in sd-boot and sd-stub measure the SMBIOS vendor strings to some PCR (at
+  least some subset of them that look like systemd stuff), because apparently
+  some firmware does not, but systemd honours it. avoid duplicate measurement
+  by sd-boot and sd-stub by adding LoaderFeatures/StubFeatures flag for this,
+  so that sd-stub can avoid it if sd-boot already did it.
+
+* cryptsetup: a mechanism that allows signing a volume key with some key that
+  has to be present in the kernel keyring, or similar, to ensure that confext
+  DDIs can be encrypted against the local SRK but signed with the admin's key
+  and thus can authenticated locally before they are decrypted.
+
+* image policy should be extended to allow dictating *how* a disk is unlocked,
+  i.e. root=encrypted-tpm2+encrypted-fido2 would mean "root fs must be
+  encrypted and unlocked via fido2 or tpm2, but not otherwise"
+
+* systemd-repart: add support for formatting dm-crypt + dm-integrity file
+  systems.
+
+* homed: use systemd-storagetm to expose home dirs via nvme-tcp. Then,
+  teach homed/pam_systemd_homed with a user name such as
+  lennart%nvme_tcp_192.168.100.77_8787 to log in from any linux host with the
+  same home dir. Similar maybe for nbd, iscsi? this should then first ask for
+  the local root pw, to authenticate that logging in like this is ok, and would
+  then be followed by another password prompt asking for the user's own
+  password. Also, do something similar for CIFS: if you log in via
+  lennart%cifs-someserver_someshare, then set up the homed dir for it
+  automatically. The PAM module should update the user name used for login to
+  the short version once it set up the user. Some care should be taken, so that
+  the long version can be still be resolved via NSS afterwards, to deal with
+  PAM clients that do not support PAM sessions where PAM_USER changes half-way.
+
+* redefine /var/lib/extensions/ as the dir one can place all three of sysext,
+  confext as well is multi-modal DDIs that qualify as both. Then introduce
+  /var/lib/sysexts/ which can be used to place only DDIs that shall be used as
+  sysext
+
+* in pid1: move out all cgroup state settings from Unit into a new object
+  CGroupState or so which is allocated when we realize the unit into a cgroup,
+  and then remains referenced by it. The new object should also carry an fd to
+  the realized cgroup, to pin it (and later execute all cgroup operations over,
+  once we drop cgroupv1 compat).
+
+* add new "systemd-ssh-generator", which allows basic ssh config via
+  credentials (host key). It generates sshd.socket for IP, but also
+  sshd-vsock.socket for listening on AF_VSOCK when running in a VM, and
+  sshd-unix.socket on AF_UNIX when running in a container. It also generates a
+  matching sshd.service file with a host key passed in on the cmdline via
+  credentials. Then, add a ssh_config drop-in that matches some suitable
+  hostname pattern and has a ProxyCommand set that allows connecting to any
+  local VM/container that way without any networking configured.
+
+* Varlinkification of the following command line tools, to open them up to
+  other programs via IPC:
+  - bootctl
+  - journalctl (allowing journal read access via IPC)
+  - coredumpcl
+  - systemd-bless-boot
+  - systemd-measure
+  - systemd-creds (allowing clients to encrypt credentials locally)
+  - systemd-cryptenroll (to allow UIs to enroll FIDO2 keys and such)
+  - systemd-dissect
+  - systemd-sysupdate
+  - systemd-analyze
+  - systemd-pcrlock (to allow fwupd to relax policy)
+  - kernel-install
+
+* Varlink: add glue code to allow varlink clients to be authenticated via
+  Polkit by passing client pidfd over.
+
+* in the service manager, pick up ERRNO= + BUSERROR= + VARLINKERROR= error
+  identifiers, and store them along with the exit status of a server and report
+  via "systemctl status".
+
+* enumerate virtiofs devices during boot-up in a generator, and synthesize
+  mounts for rootfs, /usr/, /home/, /srv/ and some others from it, depending on
+  the "tag". (waits for: https://gitlab.com/virtio-fs/virtiofsd/-/issues/128)
+
+* automatically mount one virtiofs during early boot phase to /run/host/,
+  similar to how we do that for nspawn, based on some clear tag.
+
+* add some service that makes an atomic snapshot of PCR state and event log up
+  to that point available, possibly even with quote by the TPM.
+
+* encode type1 entries in some UKI section to add additional entries to the
+  menu.
+
+* Add ACL-based access management to .socket units. i.e. add AllowPeerUser= +
+  AllowPeerGroup= that installs additional user/group ACL entries on AF_UNIX
+  sockets.
+
+* systemd-tpm2-setup should probably have a factory reset logic, i.e. when some
+  kernel command line option is set we reset the TPM (equivalent of tpm2_clear
+  -c owner?).
+
+* systemd-tpm2-setup should support a mode where we refuse booting if the SRK
+  changed. (Must be opt-in, to not break systems which are supposed to be
+  migratable between PCs)
+
+* when systemd-sysext learns mutable /usr/ (and systemd-confext mutable /etc/)
+  then allow them to store the result in a .v/ versioned subdir, for some basic
+  snapshot logic
+
+* add a new PE binary section ".mokkeys" or so which sd-stub will insert into
+  Mok keyring, by overriding/extending whatever shim sets in the EFI
+  var. Benefit: we can extend the kernel module keyring at ukify time,
+  i.e. without recompiling the kernel, taking an upstream OS' kernel and adding
+  a local key to it.
+
+* PidRef conversion work:
+  - cg_pid_get_xyz()
+  - pid_from_same_root_fs()
+  - get_ctty_devnr()
+  - pid1: sd_notify() receiver should use SCM_PIDFD to authenticate client
+  - actually wait for POLLIN on pidref's pidfd in service logic
+  - exec_spawn() + safe_fork()
+  - openpt_allocate_in_namespace()
+  - sd_bus_creds
+  - unit_attach_pid_to_cgroup_via_bus()
+  - cg_attach() – requires new kernel feature
+  - varlink_get_peer_pid()
+
+* ddi must be listed as block device fstype
+
+* measure some string via pcrphase whenever we end up booting into emergency
+  mode.
+
+* homed: add a basic form of secrets management to homed, that stores
+  secrets in $HOME somewhere, is protected by the accounts own authentication
+  mechanisms. Should implement something PKCS#11-like that can be used to
+  implement emulated FIDO2 in unpriv userspace on top (which should happen
+  outside of homed), emulated PKCS11, and libsecrets support. Operate with a
+  2nd key derived from volume key of the user, with which to wrap all
+  keys. maintain keys in kernel keyring if possible.
+
+* use sd-event ratelimit feature optionally for journal stream clients that log
+  too much
+
+* systemd-mount should only consider modern file systems when mounting, similar
+  to systemd-dissect
+
+* add another PE section ".fname" or so that encodes the intended filename for
+  PE file, and validate that when loading add-ons and similar before using
+  it. This is particularly relevant when we load multiple add-ons and want to
+  sort them to apply them in a define order. The order should not be under
+  control of the attacker.
+
+* also include packaging metadata (á la
+  https://systemd.io/ELF_PACKAGE_METADATA/) in our UEFI PE binaries, using the
+  same JSON format.
+
+* make "bootctl install" + "bootctl update" useful for installing shim too. For
+  that introduce new dir /usr/lib/systemd/efi/extra/ which we copy mostly 1:1
+  into the ESP at install time. Then make the logic smart enough so that we
+  don't overwrite bootx64.efi with our own if the extra tree already contains
+  one. Also, follow symlinks when copying, so that shim rpm can symlink their
+  stuff into our dir (which is safe since the target ESP is generally VFAT and
+  thus does not have symlinks anyway). Later, teach the update logic to look at
+  the ELF package metadata (which we also should include in all PE files, see
+  above) for version info in all *.EFI files, and use it to only update if
+  newer.
+
+* in sd-stub: optionally add support for a new PE section .keyring or so that
+  contains additional certificates to include in the Mok keyring, extending
+  what shim might have placed there. why? let's say I use "ukify" to build +
+  sign my own fedora-based UKIs, and only enroll my personal lennart key via
+  shim.  Then, I want to include the fedora keyring in it, so that kmods work.
+  But I might not want to enroll the fedora key in shim, because this would
+  also mean that the key would be in effect whenever I boot an archlinux UKI
+  built the same way, signed with the same lennart key.
+
+* resolved: take possession of some IPv6 ULA address (let's say
+  fd00:5353:5353:5353:5353:5353:5353:5353), and listen on port 53 on it for the
+  local stubs, so that we can make the stub available via ipv6 too.
+
+* introduce a .microcode PE section for sd-stub which we'll pass as first initrd
+  to the kernel which will then upload it to the CPU. This should be distinct
+  from .initrd to guarantee right ordering. also, and maybe more importantly
+  support .microcode in PE add-ons, so that a microcode update can be shipped
+  independently of any kernel.
+
+* Maybe add SwitchRootEx() as new bus call that takes env vars to set for new
+  PID 1 as argument. When adding SwitchRootEx() we should maybe also add a
+  flags param that allows disabling and enabling whether serialization is
+  requested during switch root.
+
+* introduce a .acpitable section for early ACPI table override
+
+* add proper .osrel matching for PE addons. i.e. refuse applying an addon
+  intended for a different OS. Take inspiration from how confext/sysext are
+  matched against OS.
+
+* figure out what to do about credentials sealed to PCRs in kexec + soft-reboot
+  scenarios. Maybe insist sealing is done additionally against some keypair in
+  the TPM to which access is updated on each boot, for the next, or so?
+
+* logind: when logging in, always take an fd to the home dir, to keep the dir
+  busy, so that autofs release can never happen. (this is generally a good
+  idea, and specifically works around the fact the autofs ignores busy by mount
+  namespaces)
+
+* mount most file systems with a restrictive uidmap. e.g. mount /usr/ with a
+  uidmap that blocks out anything outside 0…1000 (i.e. system users) and similar.
+
+* mount the root fs with MS_NOSUID by default, and then mount /usr/ without
+  both so that suid executables can only be placed there. Do this already in
+  the initrd. If /usr/ is not split out create a bind mount automatically.
+
+* fix our various hwdb lookup keys to end with ":" again. The original idea was
+  that hwdb patterns can match arbitrary fields with expressions like
+  "*:foobar:*", to wildcard match both the start and the end of the string.
+  This only works safely for later extensions of the string if the strings
+  always end in a colon. This requires updating our udev rules, as well as
+  checking if the various hwdb files are fine with that.
+
+* mount /tmp/ and /var/tmp with a uidmap applied that blocks out "nobody" user
+  among other things such as dynamic uid ranges for containers and so on. That
+  way no one can create files there with these uids and we enforce they are only
+  used transiently, never persistently.
+
+* rework loopback support in fstab: when "loop" option is used, then
+  instantiate a new systemd-loop@.service for the source path, set the
+  lo_file_name field for it to something recognizable derived from the fstab
+  line, and then generate a mount unit for it using a udev generated symlink
+  based on lo_file_name.
+
+* remove tomoyo support, it's obsolete and unmaintained apparently
+
+* In .socket units, add ConnectStream=, ConnectDatagram=,
+  ConnectSequentialPacket= that create a socket, and then *connect to* rather than
+  listen on some socket. Then, add a new setting WriteData= that takes some
+  base64 data that systemd will write into the socket early on. This can then
+  be used to create connections to arbitrary services and issue requests into
+  them, as long as the data is static. This can then be combined with the
+  aforementioned journald subscription varlink service, to enable
+  activation-by-message id and similar.
+
+* .service with invalid Sockets= starts successfully.
+
+* landlock: lock down RuntimeDirectory= via landlock, so that services lose
+  ability to write anywhere else below /run/. Similar for
+  StateDirectory=. Benefit would be clear delegation via unit files: services
+  get the directories they get, and nothing else even if they wanted to.
+
+* landlock: for unprivileged systemd (i.e. systemd --user), use landlock to
+  implement ProtectSystem=, ProtectHome= and so on. Landlock does not require
+  privs, and we can implement pretty similar behaviour. Also, maybe add a mode
+  where ProtectSystem= combined with an explicit PrivateMounts=no could request
+  similar behaviour for system services, too.
+
+* Add systemd-mount@.service which is instantiated for a block device and
+  invokes systemd-mount and exits. This is then useful to use in
+  ENV{SYSTEMD_WANTS} in udev rules, and a bit prettier than using RUN+=
+
+* udevd: extend memory pressure logic: also kill any idle worker processes
+
+* udevadm: to make symlink querying with udevadm nicer:
+  - do not enable the pager for queries like 'udevadm info -q -r symlink'
+  - add mode with newlines instead of spaces (for grep)?
+
+* SIGRTMIN+18 and memory pressure handling should still be added to: hostnamed,
+  localed, oomd, timedated.
+
+* repart/gpt-auto/DDIs: maybe introduce a concept of "extension" partitions,
+  that have a new type uuid and can "extend" earlier partitions, to work around
+  the fact that systemd-repart can only grow the last partition defined. During
+  activation we'd simply set up a dm-linear mapping to merge them again. A
+  partition that is to be extended would just set a bit in the partition flags
+  field to indicate that there's another extension partition to look for. The
+  identifying UUID of the extension partition would be hashed in counter mode
+  from the uuid of the original partition it extends. Inspiration for this is
+  the "dynamic partitions" concept of new Android. This would be a minimalistic
+  concept of a volume manager, with the extents it manages being exposes as GPT
+  partitions. I a partition is extended multiple times they should probably
+  grow exponentially in size to ensure O(log(n)) time for finding them on
+  access.
+
+* Use CLONE_INTO_CGROUP to spawn systemd-executor, once glibc supports it in
+  posix_spawn().
+
+* Make nspawn to a frontend for systemd-executor, so that we have to ways into
+  the executor: via unit files/dbus/varlink through PID1 and via cmdline/OCI
+  through nspawn.
+
+* sd-stub: detect if we are running with uefi console output on serial, and if so
+  automatically add console= to kernel cmdline matching the same port.
+
+* add a utility that can be used with the kernel's
+  CONFIG_STATIC_USERMODEHELPER_PATH and then handles them within pid1 so that
+  security, resource management and cgroup settings can be enforced properly
+  for all umh processes.
+
+* systemd-shutdown: keep sending sd_notify() status updates immediately before
+  going down, in particular include the "reboot param" string.
+
+* homed: when resizing an fs don't sync identity beforehand there might simply
+  not be enough disk space for that. try to be defensive and sync only after
+  resize.
+
+* homed: if for some reason the partition ended up being much smaller than
+  whole disk, recover from that, and grow it again.
+
+* timesyncd: when saving/restoring clock try to take boot time into account.
+  Specifically, along with the saved clock, store the current boot ID. When
+  starting, check if the boot id matches. If so, don't do anything (we are on
+  the same boot and clock just kept running anyway). If not, then read
+  CLOCK_BOOTTIME (which started at boot), and add it to the saved clock
+  timestamp, to compensate for the time we spent booting. If EFI timestamps are
+  available, also include that in the calculation. With this we'll then only
+  miss the time spent during shutdown after timesync stopped and before the
+  system actually reset.
+
+* systemd-stub: maybe store a "boot counter" in the ESP, and pass it down to
+  userspace to allow ordering boots (for example in journalctl). The counter
+  would be monotonically increased on every boot.
+
+* pam_systemd_home: add module parameter to control whether to only accept
+  only password or only pcks11/fido2 auth, and then use this to hook nicely
+  into two of the three PAM stacks gdm provides.
+  See discussion at https://github.com/authselect/authselect/pull/311
+
+* sd-boot: make boot loader spec type #1 accept http urls in "linux"
+  lines. Then, do the uefi http dance to download kernels and boot them. This
+  is then useful for network boot, by embedding a cpio with type #1 snippets
+  in sd-boot, which reference remote kernels.
+
+* maybe prohibit setuid() to the nobody user, to lock things down, via seccomp.
+  the nobody is not a user any code should run under, ever, as that user would
+  possibly get a lot of access to resources it really shouldn't be getting
+  access to due to the userns + nfs semantics of the user. Alternatively: use
+  the seccomp log action, and allow it.
+
+* sd-boot: add a new PE section .bls or so that carries a cpio with additional
+  boot loader entries (both type1 and type2). Then when initializing, find this
+  section, iterate through it and populate menu with it. cpio is simple enough
+  to make a parser for this reasonably robust. use same path structures as in
+  the ESP. Similar add one for signature key drop-ins.
+
+* sd-boot: also allow passing in the cpio as in the previous item via SMBIOS
+
+* add a new EFI tool "sd-fetch" or so. It looks in a PE section ".url" for an
+  URL, then downloads the file from it using UEFI HTTP APIs, and executes it.
+  Use case: provide a minimal ESP with sd-boot and a couple of these sd-fetch
+  binaries in place of UKIs, and download them on-the-fly.
+
+* maybe: systemd-loop-generator that sets up loopback devices if requested via kernel
+  cmdline. use case: include encrypted/verity root fs in UKI.
+
+* systemd-gpt-auto-generator: add kernel cmdline option to override block
+  device to dissect. also support dissecting a regular file. useccase: include
+  encrypted/verity root fs in UKI.
+
+* sd-stub: add ".bootcfg" section for kernel bootconfig data (as per
+  https://docs.kernel.org/admin-guide/bootconfig.html)
+
+* tpm2: add (optional) support for generating a local signing key from PCR 15
+  state. use private key part to sign PCR 7+14 policies. stash signatures for
+  expected PCR7+14 policies in EFI var. use public key part in disk encryption.
+  generate new sigs whenever db/dbx/mok/mokx gets updated. that way we can
+  securely bind against SecureBoot/shim state, without having to renroll
+  everything on each update (but we still have to generate one sig on each
+  update, but that should be robust/idempotent). needs rollback protection, as
+  usual.
+
+* Lennart: big blog story about DDIs
+
+* Lennart: big blog story about building initrds
+
+* Lennart: big blog story about "why systemd-boot"
+
+* bpf: see if we can use BPF to solve the syslog message cgroup source problem:
+  one idea would be to patch source sockaddr of all AF_UNIX/SOCK_DGRAM to
+  implicitly contain the source cgroup id. Another idea would be to patch
+  sendto()/connect()/sendmsg() sockaddr on-the-fly to use a different target
+  sockaddr.
+
+* bpf: see if we can address opportunistic inode sharing of immutable fs images
+  with BPF. i.e. if bpf gives us power to hook into openat() and return a
+  different inode than is requested for which we however it has same contents
+  then we can use that to implement opportunistic inode sharing among DDIs:
+  make all DDIs ship xattr on all reg files with a SHA256 hash. Then, also
+  dictate that DDIs should come with a top-level subdir where all reg files are
+  linked into by their SHA256 sum. Then, whenever an inode is opened with the
+  xattr set, check bpf table to find dirs with hashes for other prior DDIs and
+  try to use inode from there.
+
+* extend the verity signature partition to permit multiple signatures for the
+  same root hash, so that people can sign a single image with multiple keys.
+
+* consider adding a new partition type, just for /opt/ for usage in system
+  extensions
+
+* gpt-auto-discovery: also use the pkcs7 signature stuff, and pass signature to
+  kernel. So far we only did this for the various --image= switches, but not
+  for the root fs or /usr/.
+
+* dissection policy should enforce that unlocking can only take place by
+  certain means, i.e. only via pw, only via tpm2, or only via fido, or a
+  combination thereof.
+
+* make the systemd-repart "seed" value provisionable via credentials, so that
+  confidential computing environments can set it and deterministically
+  enforce the uuids for partitions created, so that they can calculate PCR 15
+  ahead of time.
+
+* systemd-repart: also derive the volume key from the seed value, for the
+  aforementioned purpose.
+
+* in the initrd: derive the default machine ID to pass to the host PID 1 via
+  $machine_id from the same seed credential.
+
+* Add systemd-sysupdate-initrd.service or so that runs systemd-sysupdate in the
+  initrd to bootstrap the initrd to populate the initial partitions. Some things
+  to figure out:
+  - Should it run on firstboot or on every boot?
+  - If run on every boot, should it use the sysupdate config from the host on
+    subsequent boots?
+
+* provide an API (probably IPC) to apps to encrypt/decrypt
+  credentials. use case: allow bluez bluetooth daemon to pass pairings to initrd
+  that way, without shelling out to our tools.
+
+* revisit default PCR bindings in cryptenroll and systemd-creds. Currently they
+  use PCR 7 which should contain secureboot state db/dbx. Which sounded like a
+  safe bet, given that it should change only on policy changes, and not
+  software updates. But that's wrong. Recent fwupd (rightfully) contains code
+  for updating the dbx denylist. This means even without any active policy
+  change PCR 7 might change. Hence, better idea might be in systemd-creds to
+  default to PCR 15 at least if sd-stub is used (i.e. bind to system identity),
+  and in cryptsetup simply the empty list? Also, PCR 14 almost certainly should
+  be included as much as PCR 7 (as it contains shim's policy, which is
+  certainly as relevant as PCR 7 on many systems)
+
+* To mimic the new tpm2-measure-pcr= crypttab option add the same to veritytab
+  (measuring the root hash) and integritytab (measuring the HMAC key if one is
+  used)
+
+* We should start measuring all services, containers, and system extensions we
+  activate. probably into PCR 13. i.e. add --tpm2-measure-pcr= or so to
+  systemd-nspawn, and MeasurePCR= to unit files. Should contain a measurement
+  of the activated configuration and the image that is being activated (in case
+  verity is used, hash of the root hash).
+
+* bootspec: permit graceful "update" from type #2 to type #1. If both a type #1
+  and a type #2 entry exist under otherwise the exact same name, then use the
+  type #1 entry, and ignore the type #2 entry. This way, people can "upgrade"
+  from the UKI with all parameters baked in to a Type #1 .conf file with manual
+  parametrization, if needed. This matches our usual rule that admin config
+  should win over vendor defaults.
+
+* write a "search path" spec, that documents the prefixes to search in
+  (i.e. the usual /etc/, /run/, /usr/lib/ dance, potentially /usr/etc/), how to
+  sort found entries, how masking works and overriding.
+
+* automatic boot assessment: add one more default success check that just waits
+  for a bit after boot, and blesses the boot if the system stayed up that long.
+
+* implement concept of "versioned" resources inside a dir, and write a spec for
+  it. Make all tools in systemd, in particular
+  RootImage=/RootDirectory=/--image=/--directory= implement this. Idea:
+  directories ending in ".v/" indicate a directory with versioned resources in
+  them. Versioned resources inside a .v dir are always named in the pattern
+  <prefix>_<version>[+<tries-left>[-<tries-done>]].<suffix>
+
+* add support for using this .v/ logic on the root fs itself: in the initrd,
+  after mounting the rootfs, look for root-<arch>.v/ in the root fs, and then
+  apply the logic, moving the switch root logic there.
+
+* systemd-repart: add support for generating ISO9660 images
+
+* systemd-repart: in addition to the existing "factory reset" mode (which
+  simply empties existing partitions marked for that). add a mode where
+  partitions marked for it are entirely removed. Use case: remove secondary OS
+  copy, and redundant partitions entirely, and recreate them anew.
+
+* systemd-boot: maybe add support for collapsing menu entries of the same OS
+  into one item that can be opened (like in a "tree view" UI element) or
+  collapsed. If only a single OS is installed, disable this mode, but if
+  multiple OSes are installed might make sense to default to it, so that user
+  is not immediately bombarded with a multitude of Linux kernel versions but
+  only one for each OS.
+
+* systemd-repart: if the GPT *disk* UUID (i.e. the one global for the entire
+  disk) is set to all FFFFF then use this as trigger for factory reset, in
+  addition to the existing mechanisms via EFI variables and kernel command
+  line. Benefit: works also on non-EFI systems, and can be requested on one
+  boot, for the next.
+
+* systemd-sysupdate: make transport pluggable, so people can plug casync or
+  similar behind it, instead of http.
+
+* systemd-tmpfiles: add concept for conditionalizing lines on factory reset
+  boot, or on first boot.
+
+* in UKIs: add way to define allowlist of additional words that can be added to
+  the kernel cmdline even in SecureBoot mode
+
+* we probably needs .pcrpkeyrd or so as additional PE section in UKIs,
+  which contains a separate public key for PCR values that only apply in the
+  initrd, i.e. in the boot phase "enter-initrd". Then, consumers in userspace
+  can easily bind resources to just the initrd. Similar, maybe one more for
+  "enter-initrd:leave-initrd" for resources that shall be accessible only
+  before unprivileged user code is allowed. (we only need this for .pcrpkey,
+  not for .pcrsig, since the latter is a list of signatures anyway). With that,
+  when you enroll a LUKS volume or similar, pick either the .pcrkey (for
+  coverage through all phases of the boot, but excluding shutdown), the
+  .pcrpkeyrd (for coverage in the initrd only) and .pcrpkeybt (for coverage
+  until users are allowed to log in).
+
+* Once the root fs LUKS volume key is measured into PCR 15, default to binding
+  credentials to PCR 15 in "systemd-creds"
+
+* add support for asymmetric LUKS2 TPM based encryption. i.e. allow preparing
+  an encrypted image on some host given a public key belonging to a specific
+  other host, so that only hosts possessing the private key in the TPM2 chip
+  can decrypt the volume key and activate the volume. Use case: systemd-confext
+  for a central orchestrator to generate confext images securely that can only
+  be activated on one specific host (which can be used for installing a bunch
+  of creds in /etc/credstore/ for example). Extending on this: allow binding
+  LUKS2 TPM based encryption also to the TPM2 internal clock. Net result:
+  prepare a confext image that can only be activated on a specific host that
+  runs a specific software in a specific time window. confext would be
+  automatically invalidated outside of it.
+
+* maybe add a "systemd-report" tool, that generates a TPM2-backed "report" of
+  current system state, i.e. a combination of PCR information, local system
+  time and TPM clock, running services, recent high-priority log
+  messages/coredumps, system load/PSI, signed by the local TPM chip, to form an
+  enhanced remote attestation quote. Use case: a simple orchestrator could use
+  this: have the report tool upload these reports every 3min somewhere. Then
+  have the orchestrator collect these reports centrally over a 3min time
+  window, and use them to determine what which node should now start/stop what,
+  and generate a small confext for each node, that uses Uphold= to pin services
+  on each node.  The confext would be encrypted using the asymmetric encryption
+  proposed above, so that it can only be activated on the specific host, if the
+  software is in a good state, and within a specific time frame. Then run a
+  loop on each node that sends report to orchestrator and then sysupdate to
+  update confext.  Orchestrator would be stateless, i.e. operate on desired
+  config and collected reports in the last 3min time window only, and thus can
+  be trivially scaled up since all instances of the orchestrator should come to
+  the same conclusions given the same inputs of reports/desired workload info.
+  Could also be used to deliver Wireguard secrets and thus to clients, thus
+  permitting zero-trust networking: secrets are rolled over via confext updates,
+  and via the time window TPM logic invalidated if node doesn't keep itself
+  updated, or becomes corrupted in some way.
+
+* in the initrd, once the rootfs encryption key has been measured to PCR 15,
+  derive default machine ID to use from it, and pass it to host PID 1.
+
+* tree-wide: convert as much as possible over to use sd_event_set_signal_exit(), instead
+  of manually hooking into SIGINT/SIGTERM
+
+* tree-wide: convert as much as possible over to SD_EVENT_SIGNAL_PROCMASK
+  instead of manual blocking.
+
+* sd-boot: for each installed OS, grey out older entries (i.e. all but the
+  newest), to indicate they are obsolete
+
+* automatically propagate LUKS password credential into cryptsetup from host
+  (i.e. SMBIOS type #11, …), so that one can unlock LUKS via VM hypervisor
+  supplied password.
+
+* add ability to path_is_valid() to classify paths that refer to a dir from
+  those which may refer to anything, and use that in various places to filter
+  early. i.e. stuff ending in "/", "/." and "/.." definitely refers to a
+  directory, and paths ending that way can be refused early in many contexts.
+
+* systemd-measure: allow operating with PEM certificates in addition to PEM
+  public keys when signing PCR values. SecureBoot and our Verity signatures
+  operate with certificates already, hence I guess we should also just deal for
+  convenience with certificates for the PCR stuff too.
+
+* systemd-measure: add --pcrpkey-auto as an alternative to --pcrpkey=, where it
+  would just use the same public key specified with --public-key= (or the one
+  automatically derived from --private-key=).
+
+* push people to use ".sysext.raw" as suffix for sysext DDIs (DDI =
+  discoverable disk images, i.e. the new name for gpt disk images following the
+  discoverable disk spec). [Also: just ".sysext/" for directory-based sysext]
+
+* Add "purpose" flag to partition flags in discoverable partition spec that
+  indicate if partition is intended for sysext, for portable service, for
+  booting and so on. Then, when dissecting DDI allow specifying a purpose to
+  use as additional search condition. Use case: images that combined a sysext
+  partition with a portable service partition in one.
+
+* On boot, auto-generate an asymmetric key pair from the TPM,
+  and use it for validating DDIs and credentials. Maybe upload it to the kernel
+  keyring, so that the kernel does this validation for us for verity and kernel
+  modules
+
+* for systemd-confext: add a tool that can generate suitable DDIs with verity +
+  sig using squashfs-tools-ng's library. Maybe just systemd-repart called under
+  a new name with a built-in config?
+
+* lock down acceptable encrypted credentials at boot, via simple allowlist,
+  maybe on kernel command line:
+  systemd.import_encrypted_creds=foobar.waldo,tmpfiles.extra to protect locked
+  down kernels from credentials generated on the host with a weak kernel
+
+* Add support for extra verity configuration options to systemd-repart (FEC,
+  hash type, etc)
+
+* chase(): take inspiration from path_extract_filename() and return
+  O_DIRECTORY if input path contains trailing slash.
+
+* chase(): refuse resolution if trailing slash is specified on input,
+  but final node is not a directory
+
+* document in boot loader spec that symlinks in XBOOTLDR/ESP are not OK even if
+  non-VFAT fs is used.
+
+* measure credentials picked up from SMBIOS to some suitable PCR
+
+* measure GPT and LUKS headers somewhere when we use them (i.e. in
+  systemd-gpt-auto-generator/systemd-repart and in systemd-cryptsetup?)
+
+* pick up creds from EFI vars
+
+* Add and pickup tpm2 metadata for creds structure.
+
+* sd-boot: we probably should include all BootXY EFI variable defined boot
+  entries in our menu, and then suppress ourselves. Benefit: instant
+  compatibility with all other OSes which register things there, in particular
+  on other disks. Always boot into them via NextBoot EFI variable, to not
+  affect PCR values.
+
+* systemd-measure tool:
+  - pre-calculate PCR 12 (command line) + PCR 13 (sysext) the same way we can precalculate PCR 11
+
+* in sd-boot: load EFI drivers from a new PE section. That way, one can have a
+  "supercharged" sd-boot binary, that could carry ext4 drivers built-in.
+
+* sd-bus: document that sd_bus_process() only returns messages that non of the
+  filters/handlers installed on the connection took possession of.
+
+* sd-device: add an API for acquiring list of child devices, given a device
+  objects (i.e. all child dirents that dirs or symlinks to dirs)
+
+* sd-device: maybe pin the sysfs dir with an fd, during the entire runtime of
+  an sd_device, then always work based on that.
+
+* maybe add new flags to gpt partition tables for rootfs and usrfs indicating
+  purpose, i.e. whether something is supposed to be bootable in a VM, on
+  baremetal, on an nspawn-style container, if it is a portable service image,
+  or a sysext for initrd, for host os, or for portable container. Then hook
+  portabled/… up to udev to watch block devices coming up with the flags set, and
+  use it.
+
+* sd-boot should look for information what to boot in SMBIOS, too, so that VM
+  managers can tell sd-boot what to boot into and suchlike
+
+* add "systemd-sysext identify" verb, that you can point on any file in /usr/
+  and that determines from which overlayfs layer it originates, which image, and with
+  what it was signed.
+
+* systemd-creds: extend encryption logic to support asymmetric
+  encryption/authentication. Idea: add new verb "systemd-creds public-key"
+  which generates a priv/pub key pair on the TPM2 and stores the priv key
+  locally in /var. It then outputs a certificate for the pub part to stdout.
+  This can then be copied/taken elsewhere, and can be used for encrypting creds
+  that only the host on its specific hw can decrypt. Then, support a drop-in
+  dir with certificates that can be used to authenticate credentials. Flow of
+  operations is then this: build image with owner certificate, then after
+  boot up issue "systemd-creds public-key" to acquire pubkey of the machine.
+  Then, when passing data to the machine, sign with privkey belonging to one of
+  the dropped in certs and encrypted with machine pubkey, and pass to machine.
+  Machine is then able to authenticate you, and confidentiality is guaranteed.
+
+* building on top of the above, the pub/priv key pair generated on the TPM2
+  should probably also one you can use to get a remote attestation quote.
+
+* Process credentials in:
+  • networkd/udevd: add a way to define additional .link, .network, .netdev files
+    via the credentials logic.
+  • crypttab-generator: allow defining additional crypttab-like volumes via
+    credentials (similar: verity-generator, integrity-generator). Use
+    fstab-generator logic as inspiration.
+  • run-generator: allow defining additional commands to run via a credential
+  • resolved: allow defining additional /etc/hosts entries via a credential (it
+    might make sense to then synthesize a new combined /etc/hosts file in /run
+    and bind mount it on /etc/hosts for other clients that want to read it.
+  • repart: allow defining additional partitions via credential
+  • timesyncd: pick NTP server info from credential
+  • portabled: read a credential "portable.extra" or so, that takes a list of
+    file system paths to enable on start.
+  • make systemd-fstab-generator look for a system credential encoding root= or
+    usr=
+  • systemd-homed: when initializing, look for a credential
+    systemd.homed.register or so with JSON user records to automatically
+    register if not registered yet.  Use case: deploy a system, and add an
+    account one can directly log into.
+  • in gpt-auto-generator: check partition uuids against such uuids supplied via
+    sd-stub credentials. That way, we can support parallel OS installations with
+    pre-built kernels.
+
+* define a JSON format for units, separating out unit definitions from unit
+  runtime state. Then, expose it:
+
+  1. Add Describe() method to Unit D-Bus object that returns a JSON object
+     about the unit.
+  2. Expose this natively via Varlink, in similar style
+  3. Use it when invoking binaries (i.e. make PID 1 fork off systemd-executor
+     binary which reads the JSON definition and runs it), to address the cow
+     trap issue and the fact that NSS is actually forbidden in
+     forked-but-not-exec'ed children
+  4. Add varlink API to run transient units based on provided JSON definitions
+
+* Add SUPPORT_END_URL= field to os-release with more *actionable* information
+  what to do if support ended
+
+* pam_systemd: on interactive logins, maybe show SUPPORT_END information at
+  login time, à la motd
+
+* sd-boot: instead of unconditionally deriving the ESP to search boot loader
+  spec entries in from the paths of sd-boot binary, let's optionally allow it
+  to be configured on sd-boot cmdline + efi var. Use case: embed sd-boot in the
+  UEFI firmware (for example, ovmf supports that via qemu cmdline option), and
+  use it to load stuff from the ESP.
+
+* mount /var/ from initrd, so that we can apply sysext and stuff before the
+  initrd transition. Specifically:
+  1. There should be a var= kernel cmdline option, matching root= and usr=
+  2. systemd-gpt-auto-generator should auto-mount /var if it finds it on disk
+  3. mount.x-initrd mount option in fstab should be implied for /var
+
+* make persistent restarts easier by adding a new setting OpenPersistentFile=
+  or so, which allows opening one or more files that is "persistent" across
+  service restarts, hot reboot, cold reboots (depending on configuration): the
+  files are created empty on first invocation, and on subsequent invocations
+  the files are reboot. The files would be backed by tmpfs, pmem or /var
+  depending on desired level of persistency.
+
+* sd-event: add ability to "chain" event sources. Specifically, add a call
+  sd_event_source_chain(x, y), which will automatically enable event source y
+  in oneshot mode once x is triggered. Use case: in src/core/mount.c implement
+  the /proc/self/mountinfo rescan on SIGCHLD with this: whenever a SIGCHLD is
+  seen, trigger the rescan defer event source automatically, and allow it to be
+  dispatched *before* the SIGCHLD is handled (based on priorities). Benefit:
+  dispatch order is strictly controlled by priorities again. (next step: chain
+  event sources to the ratelimit being over)
+
+* if we fork of a service with StandardOutput=journal, and it forks off a
+  subprocess that quickly dies, we might not be able to identify the cgroup it
+  comes from, but we can still derive that from the stdin socket its output
+  came from. We apparently don't do that right now.
+
+* add ability to set hostname with suffix derived from machine id at boot
+
+* add PR_SET_DUMPABLE service setting
+
+* homed/userdb: maybe define a "companion" dir for home directories where apps
+  can safely put privileged stuff in. Would not be writable by the user, but
+  still conceptually belong to the user. Would be included in user's quota if
+  possible, even if files are not owned by UID of user. Use case: container
+  images that owned by arbitrary UIDs, and are owned/managed by the users, but
+  are not directly belonging to the user's UID. Goal: we shouldn't place more
+  privileged dirs inside of unprivileged dirs, and thus containers really
+  should not be placed inside of traditional UNIX home dirs (which are owned by
+  users themselves) but somewhere else, that is separate, but still close
+  by. Inform user code about path to this companion dir via env var, so that
+  container managers find it. the ~/.identity file is also a candidate for a
+  file to move there, since it is managed by privileged code (i.e. homed) and
+  not unprivileged code.
+
+* given that /etc/ssh/ssh_config.d/ is a thing now, ship a drop-in for that
+  that hooks up userdbctl ssh-key stuff.
+
+* maybe add support for binding and connecting AF_UNIX sockets in the file
+  system outside of the 108ch limit. When connecting, open O_PATH fd to socket
+  inode first, then connect to /proc/self/fd/XYZ. When binding, create symlink
+  to target dir in /tmp, and bind through it.
+
+* add a proper concept of a "developer" mode, i.e. where cryptographic
+  protections of the root OS are weakened after interactive confirmation, to
+  allow hackers to allow their own stuff. idea: allow entering developer mode
+  only via explicit choice in boot menu: i.e. add explicit boot menu item for
+  it. When developer mode is entered, generate a key pair in the TPM2, and add
+  the public part of it automatically to keychain of valid code signature keys
+  on subsequent boots. Then provide a tool to sign code with the key in the
+  TPM2. Ensure that boot menu item is the only way to enter developer mode, by
+  binding it to locality/PCRs so that keys cannot be generated otherwise.
+
+* services: add support for cryptographically unlocking per-service directories
+  via TPM2. Specifically, for StateDirectory= (and related dirs) use fscrypt to
+  set up the directory so that it can only be accessed if host and app are in
+  order.
+
+* update HACKING.md to suggest developing systemd with the ideas from:
+  https://0pointer.net/blog/testing-my-system-code-in-usr-without-modifying-usr.html
+  https://0pointer.net/blog/running-an-container-off-the-host-usr.html
+
+* sd-event: compat wd reuse in inotify code: keep a set of removed watch
+  descriptors, and clear this set piecemeal when we see the IN_IGNORED event
+  for it, or when read() returns EAGAIN or on IN_Q_OVERFLOW. Then, whenever we
+  see an inotify wd event check against this set, and if it is contained ignore
+  the event. (to be fully correct this would have to count the occurrences, in
+  case the same wd is reused multiple times before we start processing
+  IN_IGNORED again)
+
+* for vendor-built signed initrds:
+  - kernel-install should be able to install encrypted creds automatically for
+    machine id, root pw, rootfs uuid, resume partition uuid, and place next to
+    EFI kernel, for sd-stub to pick them up. These creds should be locked to
+    the TPM, and bind to the right PCR the kernel is measured to.
+  - kernel-install should be able to pick up initrd sysexts automatically and
+    place them next to EFI kernel, for sd-stub to pick them up.
+  - systemd-fstab-generator should look for rootfs device to mount in creds
+  - systemd-resume-generator should look for resume partition uuid in creds
+  - sd-stub: automatically pick up microcode from ESP (/loader/microcode/*)
+    and synthesize initrd from it, and measure it. Signing is not necessary, as
+    microcode does that on its own. Pass as first initrd to kernel.
+
+* Maybe extend the service protocol to support handling of some specific SIGRT
+  signal for setting service log level, that carries the level via the
+  sigqueue() data parameter. Enable this via unit file setting.
+
+* sd_notify/vsock: maybe support binding to AF_VSOCK in Type=notify services,
+  then passing $NOTIFY_SOCKET and $NOTIFY_GUESTCID with PID1's cid (typically
+  fixed to "2", i.e. the official host cid) and the expected guest cid, for the
+  two sides of the channel. The latter env var could then be used in an
+  appropriate qemu cmdline. That way qemu payloads could talk sd_notify()
+  directly to host service manager.
+
+* sd-device has an API to create an sd_device object from a device id, but has
+  no api to query the device id
+
+* sd-device should return the devnum type (i.e. 'b' or 'c') via some API for an
+  sd_device object, so that data passed into sd_device_new_from_devnum() can
+  also be queried.
+
+* sd-event: optionally, if per-event source rate limit is hit, downgrade
+  priority, but leave enabled, and once ratelimit window is over, upgrade
+  priority again. That way we can combat event source starvation without
+  stopping processing events from one source entirely.
+
+* sd-event: similar to existing inotify support add fanotify support (given
+  that apparently new features in this area are only going to be added to the
+  latter).
+
+* sd-event: add 1st class event source for clock changes
+
+* sd-event: add 1st class event source for timezone changes
+
+* support uefi/http boots with sd-boot: instead of looking for dropin files in
+  /loader/entries/ dir, look for a file /loader/entries/SHA256SUMS and use that
+  as directory manifest. The file would be a standard directory listing as
+  generated by GNU sha256sums.
+
+* sd-boot: maybe add support for embedding the various auxiliary resources we
+  look for right in the sd-boot binary. i.e. take inspiration from sd-stub
+  logic: allow combining sd-boot via ukify with kernels to enumerate, .conf
+  files, drivers, keys to enroll and so on. Then, add whatever we find that way
+  to the menu. Use case: allow building a single PE image you can boot into via
+  UEFI HTTP boot.
+
+* maybe add a new UEFI stub binary "sd-http". It works similar to sd-stub, but
+  all it does is download a file from a http server, and execute it, after
+  optionally checking its hash sum. idea would be: combine this "sd-http" stub
+  binary with some minimal info about a URL + hash sum, plus .osrel data, and
+  drop it into the unified kernel dir in the ESP. And bam you have something
+  that is tiny, feels a lot like a unified kernel, but all it does is chainload
+  the real kernel. benefit: downloading these stubs would be tiny and quick,
+  hence cheap for enumeration.
+
+* sysext: measure all activated sysext into a TPM PCR
+
+* systemd-dissect: show available versions inside of a disk image, i.e. if
+  multiple versions are around of the same resource, show which ones. (in other
+  words: show partition labels).
+
+* maybe add a generator that reads /proc/cmdline, looks for
+  systemd.pull-raw-portable=, systemd-pull-raw-sysext= and similar switches
+  that take a URL as parameter. It then generates service units for
+  systemd-pull calls that download these URLs if not installed yet. Use case:
+  invoke a VM or nspawn container in a way it automatically deploys/runs these
+  images as OS payloads. i.e. have a generic OS image you can point to any
+  payload you like, which is then downloaded, securely verified and run.
+
+* deprecate cgroupsv1 further (print log message at boot)
+
+* systemd-dissect: add --cat switch for dumping files such as /etc/os-release
+
+* per-service sandboxing option: ProtectIds=. If used, will overmount
+  /etc/machine-id and /proc/sys/kernel/random/boot_id with synthetic files, to
+  make it harder for the service to identify the host. Depending on the user
+  setting it should be fully randomized at invocation time, or a hash of the
+  real thing, keyed by the unit name or so. Of course, there are other ways to
+  get these IDs (e.g. journal) or similar ids (e.g. MAC addresses, DMI ids, CPU
+  ids), so this knob would only be useful in combination with other lockdown
+  options. Particularly useful for portable services, and anything else that
+  uses RootDirectory= or RootImage=. (Might also over-mount
+  /sys/class/dmi/id/*{uuid,serial} with /dev/null).
+
+* doc: prep a document explaining resolved's internal objects, i.e. Query
+  vs. Question vs. Transaction vs. Stream and so on.
+
+* doc: prep a document explaining PID 1's internal logic, i.e. transactions,
+  jobs, units
+
+* bootspec: bring UEFI and userspace enumeration of bootspec entries back into
+  sync, i.e. parse out architecture field in sd-boot (currently only done in
+  userspace)
+
+* automatically ignore threaded cgroups in cg_xyz().
+
+* add linker script that implicitly adds symbol for build ID and new coredump
+  json package metadata, and use that when logging
+
+* Enable RestrictFileSystems= for all our long-running services (similar:
+  RestrictNetworkInterfaces=)
+
+* Add systemd-analyze security checks for RestrictFileSystems= and
+  RestrictNetworkInterfaces=
+
+* cryptsetup/homed: implement TOTP authentication backed by TPM2 and its
+  internal clock.
+
+* man: rework os-release(5), and clearly separate our extension-release.d/ and
+  initrd-release parts, i.e. list explicitly which fields are about what.
+
+* sysext: before applying a sysext, do a superficial validation run so that
+  things are not rearranged to wildy. I.e. protect against accidental fuckups,
+  such as masking out /usr/lib/ or so. We should probably refuse if existing
+  inodes are replaced by other types of inodes or so.
+
+* userdb: when synthesizing NSS records, pick "best" password from defined
+  passwords, not just the first. i.e. if there are multiple defined, prefer
+  unlocked over locked and prefer non-empty over empty.
+
+* maybe add a tool inspired by the GPT auto discovery spec that runs in the
+  initrd and rearranges the rootfs hierarchy via bind mounts, if
+  enabled. Specifically in some top-level dir /@auto/ it will look for
+  dirs/symlinks/subvolumes that are named after their purpose, and optionally
+  encode a version as well as assessment counters, and then mount them into the
+  file system tree to boot into, similar to how we do that for the gpt auto
+  logic. Maybe then bind mount the original root into /.superior or something
+  like that (so that update tools can look there). Further discussion in this
+  thread:
+  https://lists.freedesktop.org/archives/systemd-devel/2021-November/047059.html
+  The GPT dissection logic should automatically enable this tool whenever we
+  detect a specially marked root fs (i.e introduce a new generic root gpt type
+  for this, that is arch independent). The also implement this in the image
+  dissection logic, so that nspawn/RootImage= and so on grok it. Maybe make
+  generic enough so that it can also work for ostrees arrangements.
+
+* if a path ending in ".auto.d/" is set for RootDirectory=/RootImage= then do a
+  strverscmp() of everything inside that dir and use that. i.e. implement very
+  simple version control. Also use this in systemd-nspawn --image= and so on.
+
+* homed: while a home dir is not activated generate slightly different NSS
+  records for it, that reports the home dir as "/" and the shell as some binary
+  provided by us. Then, when an SSH login happens and SSH permits it our binary
+  is invoked. This binary can then talk to homed and activate the homedir if
+  it's not around yet, prompting the user for a password. Once that succeeded
+  we'll switch to the real user record, i.e. home dir and shell, and our tool
+  exec()s the latter. Net effect: ssh'ing into a homed account will just work:
+  we'll neatly prompt for the homedir's password if its needed. –– Building on
+  this we could take this even further: since this tool will potentially have
+  access to the client's ssh-agent (if ssh-agent forwarding is enabled) we
+  could implement SSH unlocking of a homedir with that: when enrolling a new
+  ssh pubkey in a user record we'd ask the ssh-agent to sign some random value
+  with the privkey, then use that as luks key to unlock the home dir. Will not
+  work for ECDSA keys since their signatures contain a random component, but
+  will work for RSA and Ed25519 keys.
+
+* add tiny service that decrypts encrypted user records passed via initrd
+  credential logic and drops them into /run where nss-systemd can pick them up,
+  similar to /run/host/userdb/. Use case: drop a root user JSON record there,
+  and use it in the initrd to log in as root with locally selected password,
+  for debugging purposes. Other use case: boot into qemu with regular user
+  mounted from host. maybe put this in systemd-user-sessions.service?
+
+* drop dependency on libcap, replace by direct syscalls based on
+  CapabilityQuintet we already have. (This likely allows us to drop libcap
+  dep in the base OS image)
+
+* add concept for "exitrd" as inverse of "initrd", that we can transition to at
+  shutdown, and has similar security semantics. This should then take the place
+  of dracut's shutdown logic. Should probably support sysexts too. Care needs
+  to be taken that the resulting logic ends up in RAM, i.e. is copied out of
+  on-disk storage.
+
+* userdbd: implement an additional varlink service socket that provides the
+  host user db in restricted form, then allow this to be bind mounted into
+  sandboxed environments that want the host database in minimal form. All
+  records would be stripped of all meta info, except the basic UID/name
+  info. Then use this in portabled environments that do not use PrivateUsers=1.
+
+* portabled: when extracting unit files and copying to system.attached, if a
+  .p7s is available in the image, use it to protect the system.attached copy
+  with fs-verity, so that it cannot be tampered with
+
+* logind introduce two types of sessions: "heavy" and "light". The former would
+  be our current sessions. But the latter would be a new type of session that
+  is mostly the same but does not pull in user@.service or wait for it. Then,
+  allow configuration which type of session is desired via pam_systemd
+  parameters, and then make user@.service's session one of these "light" ones.
+  People could then choose to make FTP sessions and suchlike "light" if they
+  don't want the service manager to be started for that.
+
+* /etc/veritytab: allow that the roothash column can be specified as fs path
+  including a path to an AF_UNIX path, similar to how we do things with the
+  keys of /etc/crypttab. That way people can store/provide the roothash
+  externally and provide to us on demand only.
+
+* we probably should extend the root verity hash of the root fs into some PCR
+  on boot. (i.e. maybe add a veritytab option tpm2-measure=12 or so to measure
+  it into PCR 12); Similar: we probably should extend the LUKS volume key of
+  the root fs into some PCR on boot. (i.e. maybe add a crypttab option
+  tpm2-measure=15 or so to measure it into PCR 15); once both are in place
+  update gpt-auto-discovery to generate these by default for the partitions it
+  discovers. Static vendor stuff should probably end up in PCR 12 (i.e. the
+  verity hash), with local keys in PCR 15 (i.e. the encryption volume
+  key). That way, we nicely distinguish resources supplied by the OS vendor
+  (i.e. sysext, root verity) from those inherently local (i.e. encryption key),
+  which is useful if they shall be signed separately.
+
+* in uefi stub: query firmware regarding which PCR banks are being used, store
+  that in EFI var. then use this when enrolling TPM2 in cryptsetup to verify
+  that the selected PCRs actually are used by firmware.
+
+* rework recursive read-only remount to use new mount API
+
+* PAM: pick up authentication token from credentials
+
+* when mounting disk images: if IMAGE_ID/IMAGE_VERSION is set in os-release
+  data in the image, make sure the image filename actually matches this, so
+  that images cannot be misused.
+
+* New udev block device symlink names:
+  /dev/disk/by-parttypelabel/<pttype>-<ptlabel>. Use case: if pt label is used
+  as partition image version string, this is a safe way to reference a specific
+  version of a specific partition type, in particular where related partitions
+  are processed (e.g. verity + rootfs both named "LennartOS_0.7").
+
+* sysupdate:
+  - add fuzzing to the pattern parser
+  - support casync as download mechanism
+  - "systemd-sysupdate update --all" support, that iterates through all components
+    defined on the host, plus all images installed into /var/lib/machines/,
+    /var/lib/portable/ and so on.
+  - figure out what to do about system extensions (i.e. they need to imply an
+    update component, since otherwise sysupdate.d/ files would override the
+    host's update files.)
+  - Allow invocation with a single transfer definition, i.e. with
+    --definitions= pointing to a file rather than a dir.
+  - add ability to disable implicit decompression of downloaded artifacts,
+    i.e. a Compress=no option in the transfer definitions
+
+* in sd-id128: also parse UUIDs in RFC4122 URN syntax (i.e. chop off urn:uuid: prefix)
+
+* DynamicUser= + StateDirectory= → use uid mapping mounts, too, in order to
+  make dirs appear under right UID.
+
+* systemd-sysext: optionally, run it in initrd already, before transitioning
+  into host, to open up possibility for services shipped like that.
+
+* introduce /dev/disk/root/* symlinks that allow referencing partitions on the
+  disk the rootfs is on in a reasonably secure way. (or maybe: add
+  /dev/gpt-auto-{home,srv,boot,…} similar in style to /dev/gpt-auto-root as we
+  already have it.
+
+* whenever we receive fds via SCM_RIGHTS make sure none got dropped due to the
+  reception limit the kernel silently enforces.
+
+* Add service unit setting ConnectStream= which takes IP addresses and connects to them.
+
+* Similar, Load= which takes literal data in text or base64 format, and puts it
+  into a memfd, and passes that. This enables some fun stuff, such as embedding
+  bash scripts in unit files, by combining Load= with ExecStart=/bin/bash
+  /proc/self/fd/3
+
+* add a ConnectSocket= setting to service unit files, that may reference a
+  socket unit, and which will connect to the socket defined therein, and pass
+  the resulting fd to the service program via socket activation proto.
+
+* Add a concept of ListenStream=anonymous to socket units: listen on a socket
+  that is deleted in the fs. Use case would be with ConnectSocket= above.
+
+* importd: support image signature verification with PKCS#7 + OpenBSD signify
+  logic, as alternative to crummy gpg
+
+* add "systemd-analyze debug" + AttachDebugger= in unit files: The former
+  specifies a command to execute; the latter specifies that an already running
+  "systemd-analyze debug" instance shall be contacted and execution paused
+  until it gives an OK. That way, tools like gdb or strace can be safely be
+  invoked on processes forked off PID 1.
+
+* expose MS_NOSYMFOLLOW in various places
+
+* credentials system:
+  - acquire from EFI variable?
+  - acquire via ask-password?
+  - acquire creds via keyring?
+  - pass creds via keyring?
+  - pass creds via memfd?
+  - acquire + decrypt creds from pkcs11?
+  - make systemd-cryptsetup acquire pw via creds logic
+  - make PAMName= acquire pw via creds logic
+  - make macsec/wireguard code in networkd read key via creds logic
+  - make gatwayd/remote read key via creds logic
+  - add sd_notify() command for flushing out creds not needed anymore
+  - make user manager instances create and use a user-specific key (the one in
+    /var/lib is root-only) and add --user switch to systemd-creds to use it
+
+* add tpm.target or so which is delayed until TPM2 device showed up in case
+  firmware indicates there is one.
+
+* TPM2: auto-reenroll in cryptsetup, as fallback for hosed firmware upgrades
+  and such
+
+* introduce a new group to own TPM devices
+
+* cryptsetup: add option for automatically removing empty password slot on boot
+
+* cryptsetup: optionally, when run during boot-up and password is never
+  entered, and we are on battery power (or so), power off machine again
+
+* cryptsetup: when waiting for FIDO2/PKCS#11 token, tell plymouth that, and
+  allow plymouth to abort the waiting and enter pw instead
+
+* make cryptsetup lower --iter-time
+
+* cryptsetup: allow encoding key directly in /etc/crypttab, maybe with a
+  "base64:" prefix. Useful in particular for pkcs11 mode.
+
+* cryptsetup: reimplement the mkswap/mke2fs in cryptsetup-generator to use
+  systemd-makefs.service instead.
+
+* cryptsetup:
+  - cryptsetup-generator: allow specification of passwords in crypttab itself
+  - support rd.luks.allow-discards= kernel cmdline params in cryptsetup generator
+
+* systemd-analyze netif that explains predictable interface (or networkctl)
+
+* Add service setting to run a service within the specified VRF. i.e. do the
+  equivalent of "ip vrf exec".
+
+* special case some calls of chase() to use openat2() internally, so
+  that the kernel does what we otherwise do.
+
+* add a new flag to chase() that stops chasing once the first missing
+  component is found and then allows the caller to create the rest.
+
+* make use of new glibc 2.32 APIs sigabbrev_np() and strerrorname_np().
+
+* if /usr/bin/swapoff fails due to OOM, log a friendly explanatory message about it
+
+* pid1: support new clone3() fork-into-cgroup feature
+
+* pid1: also remove PID files of a service when the service starts, not just
+  when it exits
+
+* make us use dynamically fewer deps for containers in general purpose distros:
+  o turn into dlopen() deps:
+    - kmod-libs (only when called from PID 1)
+    - libblkid (only in RootImage= handling in PID 1, but not elsewhere)
+    - libpam (only when called from PID 1)
+    - bzip2, xz, lz4 (always — gzip and zstd should probably stay static deps the way they are,
+      since they are so basic and our defaults)
+
+* seccomp: maybe use seccomp_merge() to merge our filters per-arch if we can.
+  Apparently kernel performance is much better with fewer larger seccomp
+  filters than with more smaller seccomp filters.
+
+* systemd-path: add ESP and XBOOTLDR path. Add "private" runtime/state/cache dir enum,
+  mapping to $RUNTIME_DIRECTORY, $STATE_DIRECTORY and such
+
+* seccomp: by default mask x32 ABI system wide on x86-64. it's on its way out
+
+* seccomp: don't install filters for ABIs that are masked anyway for the
+  specific service
+
+* busctl: maybe expose a verb "ping" for pinging a dbus service to see if it
+  exists and responds.
+
+* socket units: allow creating a udev monitor socket with ListenDevices= or so,
+  with matches, then activate app through that passing socket over
+
+* unify on openssl:
+  - kill gnutls support in resolved
+  - figure out what to do about libmicrohttpd, which has a hard dependency on
+    gnutls
+  - port fsprg over to a dlopen lib, then switch it to openssl
+
+* add growvol and makevol options for /etc/crypttab, similar to
+  x-systemd.growfs and x-systemd-makefs.
+
+* userdb: allow username prefix searches in varlink API, allow realname and
+  realname substr searches in varlink API
+
+* userdb: allow uid/gid range checks
+
+* userdb: allow existence checks
+
+* pid1: activation by journal search expression
+
+* when switching root from initrd to host, set the machine_id env var so that
+  if the host has no machine ID set yet we continue to use the random one the
+  initrd had set.
+
+* sd-event: add native support for P_ALL waitid() watching, then move PID 1 to
+  it for reaping assigned but unknown children. This needs to some special care
+  to operate somewhat sensibly in light of priorities: P_ALL will return
+  arbitrary processes, regardless of the priority we want to watch them with,
+  hence on each event loop iteration check all processes which we shall watch
+  with higher prio explicitly, and then watch the entire rest with P_ALL.
+
+* tweak sd-event's child watching: keep a prioq of children to watch and use
+  waitid() only on the children with the highest priority until one is waitable
+  and ignore all lower-prio ones from that point on
+
+* maybe introduce xattrs that can be set on the root dir of the root fs
+  partition that declare the volatility mode to use the image in. Previously I
+  thought marking this via GPT partition flags but that's not ideal since
+  that's outside of the LUKS encryption/verity verification, and we probably
+  shouldn't operate in a volatile mode unless we got told so from a trusted
+  source.
+
+* coredump: maybe when coredumping read a new xattr from /proc/$PID/exe that
+  may be used to mark a whole binary as non-coredumpable. Would fix:
+  https://bugs.freedesktop.org/show_bug.cgi?id=69447
+
+* teach parse_timestamp() timezones like the calendar spec already knows it
+
+* We should probably replace /etc/rc.d/README with a symlink to doc
+  content. After all it is constant vendor data.
+
+* maybe add kernel cmdline params: to force random seed crediting
+
+* introduce a new per-process uuid, similar to the boot id, the machine id, the
+  invocation id, that is derived from process creds, specifically a hashed
+  combination of AT_RANDOM + getpid() + the starttime from
+  /proc/self/status. Then add these ids implicitly when logging. Deriving this
+  uuid from these three things has the benefit that it can be derived easily
+  from /proc/$PID/ in a stable, and unique way that changes on both fork() and
+  exec().
+
+* let's not GC a unit while its ratelimits are still pending
+
+* when killing due to service watchdog timeout maybe detect whether target
+  process is under ptracing and then log loudly and continue instead.
+
+* make rfkill uaccess controllable by default, i.e. steal rule from
+  gnome-bluetooth and friends
+
+* make MAINPID= message reception checks even stricter: if service uses User=,
+  then check sending UID and ignore message if it doesn't match the user or
+  root.
+
+* maybe trigger a uevent "change" on a device if "systemctl reload xyz.device"
+  is issued.
+
+* when importing an fs tree with machined, optionally apply userns-rec-chown
+
+* when importing an fs tree with machined, complain if image is not an OS
+
+* Maybe introduce a helper safe_exec() or so, which is to execve() which
+  safe_fork() is to fork(). And then make revert the RLIMIT_NOFILE soft limit
+  to 1K implicitly, unless explicitly opted-out.
+
+* rework seccomp/nnp logic that even if User= is used in combination with
+  a seccomp option we don't have to set NNP. For that, change uid first whil
+  keeping CAP_SYS_ADMIN, then apply seccomp, the drop cap.
+
+* when no locale is configured, default to UEFI's PlatformLang variable
+
+* add a new syscall group "@esoteric" for more esoteric stuff such as bpf() and
+  usefaultd() and make systemd-analyze check for it.
+
+* paranoia: whenever we process passwords, call mlock() on the memory
+  first. i.e. look for all places we use free_and_erasep() and
+  augment them with mlock(). Also use MADV_DONTDUMP.
+  Alternatively (preferably?) use memfd_secret().
+
+* Move RestrictAddressFamily= to the new cgroup create socket
+
+* optionally: turn on cgroup delegation for per-session scope units
+
+* sd-boot: optionally, show boot menu when previous default boot item has
+  non-zero "tries done" count
+
+* augment CODE_FILE=, CODE_LINE= with something like CODE_BASE= or so which
+  contains some identifier for the project, which allows us to include
+  clickable links to source files generating these log messages. The identifier
+  could be some abberviated URL prefix or so (taking inspiration from Go
+  imports). For example, for systemd we could use
+  CODE_BASE=github.com/systemd/systemd/blob/98b0b1123cc or so which is
+  sufficient to build a link by prefixing "http://" and suffixing the
+  CODE_FILE.
+
+* Augment MESSAGE_ID with MESSAGE_BASE, in a similar fashion so that we can
+  make clickable links from log messages carrying a MESSAGE_ID, that lead to
+  some explanatory text online.
+
+* maybe extend .path units to expose fanotify() per-mount change events
+
+* hibernate/s2h: if swap is on weird storage and refuse if so
+
+* cgroups: use inotify to get notified when somebody else modifies cgroups
+  owned by us, then log a friendly warning.
+
+* beef up log.c with support for stripping ANSI sequences from strings, so that
+  it is OK to include them in log strings. This would be particularly useful so
+  that our log messages could contain clickable links for example for unit
+  files and suchlike we operate on.
+
+* importd: add ability download images for portabled + sysext
+
+* add support for "portablectl attach http://foobar.com/waaa.raw (i.e. importd integration)
+
+* sync dynamic uids/gids between host+portable srvice (i.e. if DynamicUser=1 is set for a service, make sure that the
+  selected user is resolvable in the service even if it ships its own /etc/passwd)
+
+* Fix DECIMAL_STR_MAX or DECIMAL_STR_WIDTH. One includes a trailing NUL, the
+  other doesn't. What a disaster. Probably to exclude it.
+
+* Check that users of inotify's IN_DELETE_SELF flag are using it properly, as
+  usually IN_ATTRIB is the right way to watch deleted files, as the former only
+  fires when a file is actually removed from disk, i.e. the link count drops to
+  zero and is not open anymore, while the latter happens when a file is
+  unlinked from any dir.
+
+* port systemctl, busctl, … over to format-table.[ch]'s table formatters
+
+* pid1: lock image configured with RootDirectory=/RootImage= using the usual nspawn semantics while the unit is up
+
+* add --vacuum-xyz options to coredumpctl, matching those journalctl already has.
+
+* add CopyFile= or so as unit file setting that may be used to copy files or
+  directory trees from the host to the services RootImage= and RootDirectory=
+  environment. Which we can use for /etc/machine-id and in particular
+  /etc/resolv.conf. Should be smart and do something useful on read-only
+  images, for example fall back to read-only bind mounting the file instead.
+
+* bypass SIGTERM state in unit files if KillSignal is SIGKILL
+
+* add proper dbus APIs for the various sd_notify() commands, such as MAINPID=1
+  and so on, which would mean we could report errors and such.
+
+* introduce DefaultSlice= or so in system.conf that allows changing where we
+  place our units by default, i.e. change system.slice to something
+  else. Similar, ManagerSlice= should exist so that PID1's own scope unit could
+  be moved somewhere else too. Finally machined and logind should get similar
+  options so that it is possible to move user session scopes and machines to a
+  different slice too by default. Use case: people who want to put resources on
+  the entire system, with the exception of one specific service. See:
+  https://lists.freedesktop.org/archives/systemd-devel/2018-February/040369.html
+
+* maybe rework get_user_creds() to query the user database if $SHELL is used
+  for root, but only then.
+
+* calenderspec: add support for week numbers and day numbers within a
+  year. This would allow us to define "bi-weekly" triggers safely.
+
+* sd-bus: add vtable flag, that may be used to request client creds implicitly
+  and asynchronously before dispatching the operation
+
+* sd-bus: parse addresses given in sd_bus_set_addresses immediately and not
+  only when used. Add unit tests.
+
+* make use of ethtool veth peer info in machined, for automatically finding out
+  host-side interface pointing to the container.
+
+* add some special mode to LogsDirectory=/StateDirectory=… that allows
+  declaring these directories without necessarily pulling in deps for them, or
+  creating them when starting up. That way, we could declare that
+  systemd-journald writes to /var/log/journal, which could be useful when we
+  doing disk usage calculations and so on.
+
+* deprecate RootDirectoryStartOnly= in favour of a new ExecStart= prefix char
+
+* support projid-based quota in machinectl for containers
+
+* add a way to lock down cgroup migration: a boolean, which when set for a unit
+  makes sure the processes in it can never migrate out of it
+
+* blog about fd store and restartable services
+
+* document Environment=SYSTEMD_LOG_LEVEL=debug drop-in in debugging document
+
+* rework ExecOutput and ExecInput enums so that EXEC_OUTPUT_NULL loses its
+  magic meaning and is no longer upgraded to something else if set explicitly.
+
+* in the long run: permit a system with /etc/machine-id linked to /dev/null, to
+  make it lose its identity, i.e. be anonymous. For this we'd have to patch
+  through the whole tree to make all code deal with the case where no machine
+  ID is available.
+
+* optionally, collect cgroup resource data, and store it in per-unit RRD files,
+  suitable for processing with rrdtool. Add bus API to access this data, and
+  possibly implement a CPULoad property based on it.
+
+* beef up pam_systemd to take unit file settings such as cgroups properties as
+  parameters
+
+* maybe hook up xfs/ext4 quotactl() with services? i.e. automatically manage
+  the quota of the user indicated in User= via unit file settings, like the
+  other resource management concepts. Would mix nicely with DynamicUser=1. Or
+  alternatively, do this with projids, so that we can also cover services
+  running as root. Quota should probably cover all the special dirs such as
+  StateDirectory=, LogsDirectory=, CacheDirectory=, as well as RootDirectory= if it
+  is set, plus the whole disk space any image configured with RootImage=.
+
+* In DynamicUser= mode: before selecting a UID, use disk quota APIs on relevant
+  disks to see if the UID is already in use.
+
+* Add AddUser= setting to unit files, similar to DynamicUser=1 which however
+  creates a static, persistent user rather than a dynamic, transient user. We
+  can leverage code from sysusers.d for this.
+
+* add some optional flag to ReadWritePaths= and friends, that has the effect
+  that we create the dir in question when the service is started. Example:
+
+  ReadWritePaths=:/var/lib/foobar
+
+* Add ExecMonitor= setting. May be used multiple times. Forks off a process in
+  the service cgroup, which is supposed to monitor the service, and when it
+  exits the service is considered failed by its monitor.
+
+* track the per-service PAM process properly (i.e. as an additional control
+  process), so that it may be queried on the bus and everything.
+
+* add a new "debug" job mode, that is propagated to unit_start() and for
+  services results in two things: we raise SIGSTOP right before invoking
+  execve() and turn off watchdog support. Then, use that to implement
+  "systemd-gdb" for attaching to the start-up of any system service in its
+  natural habitat.
+
+* gpt-auto logic: support encrypted swap, add kernel cmdline option to force
+  it, and honour a gpt bit about it, plus maybe a configuration file
+
+* add a percentage syntax for TimeoutStopSec=, e.g. TimeoutStopSec=150%, and
+  then use that for the setting used in user@.service. It should be understood
+  relative to the configured default value.
+
+* enable LockMLOCK to take a percentage value relative to physical memory
+
+* Permit masking specific netlink APIs with RestrictAddressFamily=
+
+* define gpt header bits to select volatility mode
+
+* ProtectClock= (drops CAP_SYS_TIMES, adds seecomp filters for settimeofday, adjtimex), sets DeviceAllow o /dev/rtc
+
+* ProtectTracing= (drops CAP_SYS_PTRACE, blocks ptrace syscall, makes /sys/kernel/tracing go away)
+
+* ProtectMount= (drop mount/umount/pivot_root from seccomp, disallow fuse via DeviceAllow, imply Mountflags=slave)
+
+* ProtectKeyRing= to take keyring calls away
+
+* RemoveKeyRing= to remove all keyring entries of the specified user
+
+* ProtectReboot= that masks reboot() and kexec_load() syscalls, prohibits kill
+  on PID 1 with the relevant signals, and makes relevant files in /sys and
+  /proc (such as the sysrq stuff) unavailable
+
+* Support ReadWritePaths/ReadOnlyPaths/InaccessiblePaths in systemd --user instances
+  via the new unprivileged Landlock LSM (https://landlock.io)
+
+* make sure the ratelimit object can deal with USEC_INFINITY as way to turn off things
+
+* in nss-systemd, if we run inside of RootDirectory= with PrivateUsers= set,
+  find a way to map the User=/Group= of the service to the right name. This way
+  a user/group for a service only has to exist on the host for the right
+  mapping to work.
+
+* add bus API for creating unit files in /etc, reusing the code for transient units
+
+* add bus API to remove unit files from /etc
+
+* add bus API to retrieve current unit file contents (i.e. implement "systemctl cat" on the bus only)
+
+* rework fopen_temporary() to make use of open_tmpfile_linkable() (problem: the
+  kernel doesn't support linkat() that replaces existing files, currently)
+
+* transient units: don't bother with actually setting unit properties, we
+  reload the unit file anyway
+
+* optionally, also require WATCHDOG=1 notifications during service start-up and shutdown
+
+* cache sd_event_now() result from before the first iteration...
+
+* PID1: find a way how we can reload unit file configuration for
+  specific units only, without reloading the whole of systemd
+
+* add an explicit parser for LimitRTPRIO= that verifies
+  the specified range and generates sane error messages for incorrect
+  specifications.
+
+* when we detect that there are waiting jobs but no running jobs, do something
+
+* PID 1 should send out sd_notify("WATCHDOG=1") messages (for usage in the --user mode, and when run via nspawn)
+
+* there's probably something wrong with having user mounts below /sys,
+  as we have for debugfs. for example, src/core/mount.c handles mounts
+  prefixed with /sys generally special.
+  https://lists.freedesktop.org/archives/systemd-devel/2015-June/032962.html
+
+* fstab-generator: default to tmpfs-as-root if only usr= is specified on the kernel cmdline
+
+* docs: bring https://www.freedesktop.org/wiki/Software/systemd/MyServiceCantGetRealtime up to date
+
+* add a job mode that will fail if a transaction would mean stopping
+  running units. Use this in timedated to manage the NTP service
+  state.
+  https://lists.freedesktop.org/archives/systemd-devel/2015-April/030229.html
+
+* The udev blkid built-in should expose a property that reflects
+  whether media was sensed in USB CF/SD card readers. This should then
+  be used to control SYSTEMD_READY=1/0 so that USB card readers aren't
+  picked up by systemd unless they contain a medium. This would mirror
+  the behaviour we already have for CD drives.
+
+* hostnamectl: show root image uuid
+
+* Find a solution for SMACK capabilities stuff:
+  https://lists.freedesktop.org/archives/systemd-devel/2014-December/026188.html
+
+* synchronize console access with BSD locks:
+  https://lists.freedesktop.org/archives/systemd-devel/2014-October/024582.html
+
+* as soon as we have sender timestamps, revisit coalescing multiple parallel daemon reloads:
+  https://lists.freedesktop.org/archives/systemd-devel/2014-December/025862.html
+
+* figure out when we can use the coarse timers
+
+* maybe allow timer units with an empty Units= setting, so that they
+  can be used for resuming the system but nothing else.
+
+* what to do about udev db binary stability for apps? (raw access is not an option)
+
+* exponential backoff in timesyncd when we cannot reach a server
+
+* timesyncd: add ugly bus calls to set NTP servers per-interface, for usage by NM
+
+* add systemd.abort_on_kill or some other such flag to send SIGABRT instead of SIGKILL
+  (throughout the codebase, not only PID1)
+
+* drop nss-myhostname in favour of nss-resolve?
+
+* resolved:
+  - mDNS/DNS-SD
+        - service registration
+        - service/domain/types browsing
+        - avahi compat
+  - DNS-SD service registration from socket units
+  - resolved should optionally register additional per-interface LLMNR
+    names, so that for the container case we can establish the same name
+    (maybe "host") for referencing the server, everywhere.
+  - allow clients to request DNSSEC for a single lookup even if DNSSEC is off (?)
+  - hook up resolved with machined-based address resolution
+
+* refcounting in sd-resolve is borked
+
+* add new gpt type for btrfs volumes
+
+* generator that automatically discovers btrfs subvolumes, identifies their purpose based on some xattr on them.
+
+* a way for container managers to turn off getty starting via $container_headless= or so...
+
+* figure out a nice way how we can let the admin know what child/sibling unit causes cgroup membership for a specific unit
+
+* For timer units: add some mechanisms so that timer units that trigger immediately on boot do not have the services
+  they run added to the initial transaction and thus confuse Type=idle.
+
+* add bus api to query unit file's X fields.
+
+* gpt-auto-generator:
+  - Define new partition type for encrypted swap? Support probed LUKS for encrypted swap?
+  - Make /home automount rather than mount?
+
+* add generator that pulls in systemd-network from containers when
+  CAP_NET_ADMIN is set, more than the loopback device is defined, even
+  when it is otherwise off
+
+* MessageQueueMessageSize= (and suchlike) should use parse_iec_size().
+
+* implement Distribute= in socket units to allow running multiple
+  service instances processing the listening socket, and open this up
+  for ReusePort=
+
+* cgroups:
+  - implement per-slice CPUFairScheduling=1 switch
+  - introduce high-level settings for RT budget, swappiness
+  - how to reset dynamically changed unit cgroup attributes sanely?
+  - when reloading configuration, apply new cgroup configuration
+  - when recursively showing the cgroup hierarchy, optionally also show
+    the hierarchies of child processes
+  - add settings for cgroup.max.descendants and cgroup.max.depth,
+    maybe use them for user@.service
+
+* transient units:
+  - add field to transient units that indicate whether systemd or somebody else saves/restores its settings, for integration with libvirt
+
+* when we detect low battery and no AC on boot, show pretty splash and refuse boot
+
+* libsystemd-journal, libsystemd-login, libudev: add calls to easily attach these objects to sd-event event loops
+
+* be more careful what we export on the bus as (usec_t) 0 and (usec_t) -1
+
+* rfkill,backlight: we probably should run the load tools inside of the udev rules so that the state is properly initialized by the time other software sees it
+
+* If we try to find a unit via a dangling symlink, generate a clean
+  error. Currently, we just ignore it and read the unit from the search
+  path anyway.
+
+* refuse boot if /usr/lib/os-release is missing or /etc/machine-id cannot be set up
+
+* man: the documentation of Restart= currently is very misleading and suggests the tools from ExecStartPre= might get restarted.
+
+* load .d/*.conf dropins for device units
+
+* There's currently no way to cancel fsck (used to be possible via C-c or c on the console)
+
+* add option to sockets to avoid activation. Instead just drop packets/connections, see http://cyberelk.net/tim/2012/02/15/portreserve-systemd-solution/
+
+* make sure systemd-ask-password-wall does not shutdown systemd-ask-password-console too early
+
+* verify that the AF_UNIX sockets of a service in the fs still exist
+  when we start a service in order to avoid confusion when a user
+  assumes starting a service is enough to make it accessible
+
+* Make it possible to set the keymap independently from the font on
+  the kernel cmdline. Right now setting one resets also the other.
+
+* and a dbus call to generate target from current state
+
+* investigate whether the gnome pty helper should be moved into systemd, to provide cgroup support.
+
+* dot output for --test showing the 'initial transaction'
+
+* be able to specify a forced restart of service A where service B depends on, in case B
+  needs to be auto-respawned?
+
+* pid1:
+  - When logging about multiple units (stopping BoundTo units, conflicts, etc.),
+    log both units as UNIT=, so that journalctl -u triggers on both.
+  - generate better errors when people try to set transient properties
+    that are not supported...
+    https://lists.freedesktop.org/archives/systemd-devel/2015-February/028076.html
+  - maybe introduce WantsMountsFor=? Use case:
+    https://lists.freedesktop.org/archives/systemd-devel/2015-January/027729.html
+  - recreate systemd's D-Bus private socket file on SIGUSR2
+  - move PAM code into its own binary
+  - when we automatically restart a service, ensure we restart its rdeps, too.
+  - hide PAM options in fragment parser when compile time disabled
+  - Support --test based on current system state
+  - If we show an error about a unit (such as not showing up) and it has no Description string, then show a description string generated form the reverse of unit_name_mangle().
+  - after deserializing sockets in socket.c we should reapply sockopts and things
+  - drop PID 1 reloading, only do reexecing (difficult: Reload()
+    currently is properly synchronous, Reexec() is weird, because we
+    cannot delay the response properly until we are back, so instead of
+    being properly synchronous we just keep open the fd and close it
+    when done. That means clients do not get a successful method reply,
+    but much rather a disconnect on success.
+  - when breaking cycles drop sysv services first, then services from /run, then from /etc, then from /usr
+  - when a bus name of a service disappears from the bus make sure to queue further activation requests
+  - maybe introduce CoreScheduling=yes/no to optionally set a PR_SCHED_CORE cookie, so that all
+    processes in a service's cgroup share the same cookie and are guaranteed not to share SMT cores
+    with other units https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/hw-vuln/core-scheduling.rst
+
+* unit files:
+  - allow port=0 in .socket units
+  - maybe introduce ExecRestartPre=
+  - implement Register= switch in .socket units to enable registration
+    in Avahi, RPC and other socket registration services.
+  - allow Type=simple with PIDFile=
+    https://bugzilla.redhat.com/show_bug.cgi?id=723942
+  - allow writing multiple conditions in unit files on one line
+  - introduce Type=pid-file
+  - add a concept of RemainAfterExit= to scope units
+  - Allow multiple ExecStart= for all Type= settings, so that we can cover rescue.service nicely
+  - add verification of [Install] section to systemd-analyze verify
+
+* timer units:
+  - timer units should get the ability to trigger when DST changes
+  - Modulate timer frequency based on battery state
+
+* add libsystemd-password or so to query passwords during boot using the password agent logic
+
+* clean up date formatting and parsing so that all absolute/relative timestamps we format can also be parsed
+
+* on shutdown: move utmp, wall, audit logic all into PID 1 (or logind?), get rid of systemd-update-utmp-runlevel
+
+* make repeated alt-ctrl-del presses printing a dump
+
+* currently x-systemd.timeout is lost in the initrd, since crypttab is copied into dracut, but fstab is not
+
+* add a pam module that passes the hdd passphrase into the PAM stack and then expires it, for usage by gdm auto-login.
+
+* add a pam module that on password changes updates any LUKS slot where the password matches
+
+* test/:
+  - add unit tests for config_parse_device_allow()
+
+* seems that when we follow symlinks to units we prefer the symlink
+  destination path over /etc and /usr. We should not do that. Instead
+  /etc should always override /run+/usr and also any symlink
+  destination.
+
+* when isolating, try to figure out a way how we implicitly can order
+  all units we stop before the isolating unit...
+
+* teach ConditionKernelCommandLine= globs or regexes (in order to match foobar={no,0,off})
+
+* Add ConditionDirectoryNotEmpty= handle non-absoute paths as a search path or add
+  ConditionConfigSearchPathNotEmpty= or different syntax? See the discussion starting at
+  https://github.com/systemd/systemd/pull/15109#issuecomment-607740136.
+
+* BootLoaderSpec: Define a way how an installer can figure out whether a BLS
+  compliant boot loader is installed.
+
+* think about requeuing jobs when daemon-reload is issued? use case:
+  the initrd issues a reload after fstab from the host is accessible
+  and we might want to requeue the mounts local-fs acquired through
+  that automatically.
+
+* systemd-inhibit: make taking delay locks useful: support sending SIGINT or SIGTERM on PrepareForSleep()
+
+* remove any syslog support from log.c — we probably cannot do this before split-off udev is gone for good
+
+* shutdown logging: store to EFI var, and store to USB stick?
+
+* merge unit_kill_common() and unit_kill_context()
+
+* add a dependency on standard-conf.xml and other included files to man pages
+
+* MountFlags=shared acts as MountFlags=slave right now.
+
+* properly handle loop back mounts via fstab, especially regards to fsck/passno
+
+* initialize the hostname from the fs label of /, if /etc/hostname does not exist?
+
+* sd-bus:
+  - EBADSLT handling
+  - GetAllProperties() on a non-existing object does not result in a failure currently
+  - port to sd-resolve for connecting to TCP dbus servers
+  - see if we can introduce a new sd_bus_get_owner_machine_id() call to retrieve the machine ID of the machine of the bus itself
+  - see if we can drop more message validation on the sending side
+  - add API to clone sd_bus_message objects
+  - longer term: priority inheritance
+  - dbus spec updates:
+       - NameLost/NameAcquired obsolete
+       - path escaping
+  - update systemd.special(7) to mention that dbus.socket is only about the compatibility socket now
+
+* sd-event
+  - allow multiple signal handlers per signal?
+  - document chaining of signal handler for SIGCHLD and child handlers
+  - define more intervals where we will shift wakeup intervals around in, 1h, 6h, 24h, ...
+  - maybe support iouring as backend, so that we allow hooking read and write
+    operations instead of IO ready events into event loops. See considerations
+    here:
+    http://blog.vmsplice.net/2020/07/rethinking-event-loop-integration-for.html
+
+* dbus: when a unit failed to load (i.e. is in UNIT_ERROR state), we
+  should be able to safely try another attempt when the bus call LoadUnit() is invoked.
+
+* document org.freedesktop.MemoryAllocation1
+
+* maybe do not install getty@tty1.service symlink in /etc but in /usr?
+
+* print a nicer explanation if people use variable/specifier expansion in ExecStart= for the first word
+
+* mount: turn dependency information from /proc/self/mountinfo into dependency information between systemd units.
+
+* EFI:
+  - honor language efi variables for default language selection (if there are any?)
+  - honor timezone efi variables for default timezone selection (if there are any?)
+  - change bootctl to be backed by systemd-bootd to control temporary and persistent default boot goal plus efi variables
+* bootctl
+  - recognize the case when not booted on EFI
+
+* bootctl,sd-boot: actually honour the "architecture" key
+
+* bootctl:
+  - show whether UEFI audit mode is available
+  - teach it to prepare an ESP wholesale, i.e. with mkfs.vfat invocation
+  - teach it to copy in unified kernel images and maybe type #1 boot loader spec entries from host
+
+* logind:
+  - logind: optionally, ignore idle-hint logic for autosuspend, block suspend as long as a session is around
+  - logind: wakelock/opportunistic suspend support
+  - Add pretty name for seats in logind
+  - logind: allow showing logout dialog from system?
+  - add Suspend() bus calls which take timestamps to fix double suspend issues when somebody hits suspend and closes laptop quickly.
+  - if pam_systemd is invoked by su from a process that is outside of a
+    any session we should probably just become a NOP, since that's
+    usually not a real user session but just some system code that just
+    needs setuid().
+  - logind: make the Suspend()/Hibernate() bus calls wait for the for
+    the job to be completed. before returning, so that clients can wait
+    for "systemctl suspend" to finish to know when the suspending is
+    complete.
+  - logind: when the power button is pressed short, just popup a
+    logout dialog. If it is pressed for 1s, do the usual
+    shutdown. Inspiration are Macs here.
+  - expose "Locked" property on logind session objects
+  - maybe allow configuration of the StopTimeout for session scopes
+  - rename session scope so that it includes the UID. THat way
+    the session scope can be arranged freely in slices and we don't have
+    make assumptions about their slice anymore.
+  - follow PropertiesChanged state more closely, to deal with quick logouts and
+    relogins
+  - (optionally?) spawn seat-manager@$SEAT.service whenever a seat shows up that as CanGraphical set
+  - expose details of boot entries on the bus. In particular, it should be possible
+    to query the list of boot entry titles that bootctl / sd-boot would show.
+    Currently we only expose their identifiers.
+
+* move multiseat vid/pid matches from logind udev rule to hwdb
+
+* logind: rework pam_logind to also do a bus call in case of invocation from
+  user@.service, which returns the XDG_RUNTIME_DIR value, and make this
+  behaviour selectable via pam module option.
+
+* delay activation of logind until somebody logs in, or when /dev/tty0 pulls it
+  in or lingering is on (so that containers don't bother with it until PAM is used). also exit-on-idle
+
+* journal:
+  - consider introducing implicit _TTY= + _PPID= + _EUID= + _EGID= + _FSUID= + _FSGID= fields
+  - journald: also get thread ID from client, plus thread name
+  - journal: when waiting for journal additions in the client always sleep at least 1s or so, in order to minimize wakeups
+  - add API to close/reopen/get fd for journal client fd in libsystemd-journal.
+  - fall back to /dev/log based logging in libsystemd-journal, if we cannot log natively?
+  - declare the local journal protocol stable in the wiki interface chart
+  - sd-journal: speed up sd_journal_get_data() with transparent hash table in bg
+  - journald: when dropping msgs due to ratelimit make sure to write
+    "dropped %u messages" not only when we are about to print the next
+    message that works, but already after a short timeout
+  - check if we can make journalctl by default use --follow mode inside of less if called without args?
+  - maybe add API to send pairs of iovecs via sd_journal_send
+  - journal: add a setgid "systemd-journal" utility to invoke from libsystemd-journal, which passes fds via STDOUT and does PK access
+  - journalctl: support negative filtering, i.e. FOOBAR!="waldo",
+    and !FOOBAR for events without FOOBAR.
+  - journal: store timestamp of journal_file_set_offline() in the header,
+    so it is possible to display when the file was last synced.
+  - journal-send.c, log.c: when the log socket is clogged, and we drop, count this and write a message about this when it gets unclogged again.
+  - journal: find a way to allow dropping history early, based on priority, other rules
+  - journal: When used on NFS, check payload hashes
+  - journald: add kernel cmdline option to disable ratelimiting for debug purposes
+  - refuse taking lower-case variable names in sd_journal_send() and friends.
+  - journald: we currently rotate only after MaxUse+MaxFilesize has been reached.
+  - journal: deal nicely with byte-by-byte copied files, especially regards header
+  - journal: sanely deal with entries which are larger than the individual file size, but where the components would fit
+  - Replace utmp, wtmp, btmp, and lastlog completely with journal
+  - journalctl: instead --after-cursor= maybe have a --cursor=XYZ+1 syntax?
+  - when a kernel driver logs in a tight loop, we should ratelimit that too.
+  - journald: optionally, log debug messages to /run but everything else to /var
+  - journald: when we drop syslog messages because the syslog socket is
+    full, make sure to write how many messages are lost as first thing
+    to syslog when it works again.
+  - journald: allow per-priority and per-service retention times when rotating/vacuuming
+  - journald: make use of uid-range.h to managed uid ranges to split
+    journals in.
+  - journalctl: add the ability to look for the most recent process of a binary. journalctl /usr/bin/X11 --pid=-1 or so...
+  - improve journalctl performance by loading journal files
+    lazily. Encode just enough information in the file name, so that we
+    do not have to open it to know that it is not interesting for us, for
+    the most common operations.
+  - man: document that corrupted journal files is nothing to act on
+  - rework journald sigbus stuff to use mutex
+  - Set RLIMIT_NPROC for systemd-journal-xyz, and all other of our
+    services that run under their own user ids, and use User= (but only
+    in a world where userns is ubiquitous since otherwise we cannot
+    invoke those daemons on the host AND in a container anymore). Also,
+    if LimitNPROC= is used without User= we should warn and refuse
+    operation.
+  - journalctl --verify: don't show files that are currently being
+    written to as FAIL, but instead show that they are being written to.
+  - add journalctl -H that talks via ssh to a remote peer and passes through
+    binary logs data
+  - add a version of --merge which also merges /var/log/journal/remote
+  - journalctl: -m should access container journals directly by enumerating
+    them via machined, and also watch containers coming and going.
+    Benefit: nspawn --ephemeral would start working nicely with the journal.
+  - assign MESSAGE_ID to log messages about failed services
+  - check if loop in decompress_blob_xz() is necessary
+
+* journald: support RFC3164 fully for the incoming syslog transport, see
+  https://github.com/systemd/systemd/issues/19251#issuecomment-816601955
+
+* Hook up journald's FSS logic with TPM2: seal the verification disk by
+  time-based policy, so that the verification key can remain on host and ve
+  validated via TPM.
+
+* rework journalctl -M to be based on a machined method that generates a mount
+  fd of the relevant journal dirs in the container with uidmapping applied to
+  allow the host to read it, while making everything read-only.
+
+* journald: add varlink service that allows subscribing to certain log events,
+  for example matching by message ID, or log level returns a list of journal
+  cursors as they happen.
+
+* journald: also collect CLOCK_BOOTTIME timestamps per log entry. Then, derive
+  "corrected" CLOCK_REALTIME information on display from that and the timestamp
+  info of the newest entry of the specific boot (as identified by the boot
+  ID). This way, if a system comes up without a valid clock but acquires a
+  better clock later, we can "fix" older entry timestamps on display, by
+  calculating backwards. We cannot use CLOCK_MONOTONIC for this, since it does
+  not account for suspend phases. This would then also enable us to correct the
+  kmsg timestamping we consume (where we erroneously assume the clock was in
+  CLOCK_MONOTONIC, but it actually is CLOCK_BOOTTIME as per kernel).
+
+* in journald, write out a recognizable log record whenever the system clock is
+  changed ("stepped"), and in timesyncd whenever we acquire an NTP fix
+  ("slewing"). Then, in journalctl for each boot time we come across, find
+  these records, and use the structured info they include to display
+  "corrected" wallclock time, as calculated from the monotonic timestamp in the
+  log record, adjusted by the delta declared in the structured log record.
+
+* in journald: whenever we start a new journal file because the boot ID
+  changed, let's generate a recognizable log record containing info about old
+  and new ID. Then, when displaying log stream in journalctl look for these
+  records, to be able to order them.
+
+* journald: generate recognizable log events whenever we shutdown journald
+  cleanly, and when we migrate run → var. This way tools can verify that a
+  previous boot terminated cleanly, because either of these two messages must
+  be safely written to disk, then.
+
+* hook up journald with TPMs? measure new journal records to the TPM in regular
+  intervals, validate the journal against current TPM state with that. (taking
+  inspiration from IMA log)
+
+* sd-journal puts a limit on parallel journal files to view at once. journald
+  should probably honour that same limit (JOURNAL_FILES_MAX) when vacuuming to
+  ensure we never generate more files than we can actually view.
+
+* maybe add a tool that displays most recent journal logs as QR code to scan
+  off screen and run it automatically on boot failures, emergency logs and
+  such. Use DRM APIs directly, see
+  https://github.com/dvdhrm/docs/blob/master/drm-howto/modeset.c for an example
+  for doing that.
+
+* maybe implicitly attach monotonic+realtime timestamps to outgoing messages in
+  log.c and sd-journal-send
+
+* journalctl/timesyncd: whenever timesyncd acquires a synchronization from NTP,
+  create a structured log entry that contains boot ID, monotonic clock and
+  realtime clock (I mean, this requires no special work, as these three fields
+  are implicit). Then in journalctl when attempting to display the realtime
+  timestamp of a log entry, first search for the closest later log entry
+  of this kinda that has a matching boot id, and convert the monotonic clock
+  timestamp of the entry to the realtime clock using this info. This way we can
+  retroactively correct the wallclock timestamps, in particular for systems
+  without RTC, i.e. where initially wallclock timestamps carry rubbish, until
+  an NTP sync is acquired.
+
+* introduce per-unit (i.e. per-slice, per-service) journal log size limits.
+
+* journald: do journal file writing out-of-process, with one writer process per
+  client UID, so that synthetic hash table collisions can slow down a specific
+  user's journal stream down but not the others.
+
+* tweak journald context caching. In addition to caching per-process attributes
+  keyed by PID, cache per-cgroup attributes (i.e. the various xattrs we read)
+  keyed by cgroup path, and guarded by ctime changes. This should provide us
+  with a nice speed-up on services that have many processes running in the same
+  cgroup.
+
+* maybe add call sd_journal_set_block_timeout() or so to set SO_SNDTIMEO for
+  the sd-journal logging socket, and, if the timeout is set to 0, sets
+  O_NONBLOCK on it. That way people can control if and when to block for
+  logging.
+
+* journalctl: make sure -f ends when the container indicated by -M terminates
+
+* journald: sigbus API via a signal-handler safe function that people may call
+  from the SIGBUS handler
+
+* add a test if all entries in the catalog are properly formatted.
+    (Adding dashes in a catalog entry currently results in the catalog entry
+     being silently skipped. journalctl --update-catalog must warn about this,
+     and we should also have a unit test to check that all our message are OK.)
+
+* build short web pages out of each catalog entry, build them along with man
+  pages, and include hyperlinks to them in the journal output
+
+* homed:
+  - when user tries to log into record signed by unrecognized key, automatically add key to our chain after polkit auth
+  - rollback when resize fails mid-operation
+  - GNOME's side for forget key on suspend (requires rework so that lock screen runs outside of uid)
+  - update LUKS password on login if we find there's a password that unlocks the JSON record but not the LUKS device.
+  - create on activate?
+  - properties: icon url?, preferred session type?, administrator bool (which translates to 'wheel' membership)?, address?, telephone?, vcard?, samba stuff?, parental controls?
+  - communicate clearly when usb stick is safe to remove. probably involves
+    beefing up logind to make pam session close hook synchronous and wait until
+    systemd --user is shut down.
+  - logind: maybe keep a "busy fd" as long as there's a non-released session around or the user@.service
+  - maybe make automatic, read-only, time-based reflink-copies of LUKS disk
+    images (and btrfs snapshots of subvolumes) (think: time machine)
+  - distinguish destroy / remove (i.e. currently we can unregister a user, unregister+remove their home directory, but not just remove their home directory)
+  - in systemd's PAMName= logic: query passwords with ssh-askpassword, so that we can make "loginctl set-linger" mode work
+  - fingerprint authentication, pattern authentication, …
+  - make sure "classic" user records can also be managed by homed
+  - make size of $XDG_RUNTIME_DIR configurable in user record
+  - query password from kernel keyring first
+  - update even if record is "absent"
+  - move acct mgmt stuff from pam_systemd_home to pam_systemd?
+  - when "homectl --pkcs11-token-uri=" is used, synthesize ssh-authorized-keys records for all keys we have private keys on the stick for
+  - make slice for users configurable (requires logind rework)
+  - logind: populate auto-login list bus property from PKCS#11 token
+  - when determining state of a LUKS home directory, check DM suspended sysfs file
+  - when homed is in use, maybe start the user session manager in a mount namespace with MS_SLAVE,
+    so that mounts propagate down but not up - eg, user A setting up a backup volume
+    doesn't mean user B sees it
+  - use credentials logic/TPM2 logic to store homed signing key
+  - permit multiple user record signing keys to be used locally, and pick
+    the right one for signing records automatically depending on a pre-existing
+    signature
+  - add a way to "adopt" a home directory, i.e. strip foreign signatures
+    and insert a local signature instead.
+  - as an extension to the directory+subvolume backend: if located on
+    especially marked fs, then sync down password into LUKS header of that fs,
+    and always verify passwords against it too. Bootstrapping is a problem
+    though: if no one is logged in (or no other user even exists yet), how do you
+    unlock the volume in order to create the first user and add the first pw.
+  - support new FS_IOC_ADD_ENCRYPTION_KEY ioctl for setting up fscrypt
+  - maybe pre-create ~/.cache as subvol so that it can have separate quota
+    easily?
+  - add a switch to homectl (maybe called --first-boot) where it will check if
+    any non-system users exist, and if not prompts interactively for basic user
+    info, mimicking systemd-firstboot. Then, place this in a service that runs
+    after systemd-homed, but before gdm and friends, as a simple, barebones
+    fallback logic to get a regular user created on uninitialized systems.
+  - store PKCS#11 + FIDO2 token info in LUKS2 header, compatible with
+    systemd-cryptsetup, so that it can unlock homed volumes
+  - maybe make all *.home files owned by `systemd-home` user or so, so that we
+    can easily set overall quota for all users
+  - on login, if we can't fallocate initially, but rebalance is on, then allow
+    login in discard mode, then immediately rebalance, then turn off discard
+  - extend user records with optional "bulk" data. Specifically, a user
+    avatar/photo or so. This data should be stored along with the user record,
+    but probably shouldn't be part of the record itself, since it might be
+    large.
+  - add "homectl unbind" command to remove local user record of an inactive
+    home dir
+
+* add a new switch --auto-definitions=yes/no or so to systemd-repart. If
+  specified, synthesize a definition automatically if we can: enlarge last
+  partition on disk, but only if it is marked for growing and not read-only.
+
+* systemd-repart: read LUKS encryption key from $CREDENTIALS_DIRECTORY
+
+* systemd-repart: add a switch to factory reset the partition table without
+  immediately applying the new configuration again. i.e. --factory-reset=leave
+  or so. (this is useful to factory reset an image, then putting it into
+  another machine, ensuring that luks key is generated on new machine, not old)
+
+* systemd-repart: support setting up dm-integrity with HMAC
+
+* systemd-repart: maybe remove half-initialized image on failure. It fails
+  if the output file exists, so a repeated invocation will usually fail if
+  something goes wrong on the way.
+
+* systemd-repart: by default generate minimized partition tables (i.e. tables
+  that only cover the space actually used, excluding any free space at the
+  end), in order to maximize dd'ability. Requires libfdisk work, see
+  https://github.com/karelzak/util-linux/issues/907
+
+* systemd-repart: MBR partition table support. Care needs to be taken regarding
+  Type=, so that partition definitions can sanely apply to both the GPT and the
+  MBR case. Idea: accept syntax "Type=gpt:home mbr:0x83" for setting the types
+  for the two partition types explicitly. And provide an internal mapping so
+  that "Type=linux-generic" maps to the right types for both partition tables
+  automatically.
+
+* systemd-repart: allow sizing partitions as factor of available RAM, so that
+  we can reasonably size swap partitions for hibernation.
+
+* systemd-repart: allow boolean option that ensures that if existing partition
+  doesn't exist within the configured size bounds the whole command fails. This
+  is useful to implement ESP vs. XBOOTLDR schemes in installers: have one set
+  of repart files for the case where ESP is large enough and one where it isn't
+  and XBOOTLDR is added in instead.  Then apply the former first, and if it
+  fails to apply use the latter.
+
+* systemd-repart: add per-partition option to never reuse existing partition
+  and always create anew even if matching partition already exists.
+
+* systemd-repart: add per-partition option to fail if partition already exist,
+  i.e. is not added new. Similar, add option to fail if partition does not exist yet.
+
+* systemd-repart: allow disabling growing of specific partitions, or making
+  them (think ESP: we don't ever want to grow it, since we cannot resize vfat)
+  Also add option to disable operation via kernel command line.
+
+* systemd-repart: make it a static checker during early boot for existence and
+  absence of other partitions for trusted boot environments
+
+* systemd-repart: add support for SD_GPT_FLAG_GROWFS also on real systems, i.e.
+  generate some unit to actually enlarge the fs after growing the partition
+  during boot.
+
+* systemd-repart: do not print "Successfully resized …" when no change was done.
+
+* document:
+  - document that deps in [Unit] sections ignore Alias= fields in
+    [Install] units of other units, unless those units are disabled
+  - man: clarify that time-sync.target is not only sysv compat but also useful otherwise. Same for similar targets
+  - document that service reload may be implemented as service reexec
+  - add a man page containing packaging guidelines and recommending usage of things like Documentation=, PrivateTmp=, PrivateNetwork= and ReadOnlyDirectories=/etc /usr.
+  - document systemd-journal-flush.service properly
+  - documentation: recommend to connect the timer units of a service to the service via Also= in [Install]
+  - man: document the very specific env the shutdown drop-in tools live in
+  - man: add more examples to man pages,
+  -      in particular an example how to do the equivalent of switching runlevels
+  - man: maybe sort directives in man pages, and take sections from --help and apply them to man too
+  - document root=gpt-auto properly
+
+* systemctl:
+  - add systemctl switch to dump transaction without executing it
+  - Add a verbose mode to "systemctl start" and friends that explains what is being done or not done
+  - "systemctl disable" on a static unit prints no message and does
+    nothing. "systemctl enable" does nothing, and gives a bad message
+    about it. Should fix both to print nice actionable messages.
+  - print nice message from systemctl --failed if there are no entries shown, and hook that into ExecStartPre of rescue.service/emergency.service
+  - add new command to systemctl: "systemctl system-reexec" which reexecs as many daemons as virtually possible
+  - systemctl enable: fail if target to alias into does not exist? maybe show how many units are enabled afterwards?
+  - systemctl: "Journal has been rotated since unit was started." message is misleading
+  - systemctl status output should include list of triggering units and their status
+
+* introduce an option (or replacement) for "systemctl show" that outputs all
+  properties as JSON, similar to busctl's new JSON output. In contrast to that
+  it should skip the variant type string though.
+
+* Add a "systemctl list-units --by-slice" mode or so, which rearranges the
+  output of "systemctl list-units" slightly by showing the tree structure of
+  the slices, and the units attached to them.
+
+* add "systemctl wait" or so, which does what "systemd-run --wait" does, but
+  for all units. It should be both a way to pin units into memory as well as a
+  wait to retrieve their exit data.
+
+* show whether a service has out-of-date configuration in "systemctl status" by
+  using mtime data of ConfigurationDirectory=.
+
+* "systemctl preset-all" should probably order the unit files it
+  operates on lexicographically before starting to work, in order to
+  ensure deterministic behaviour if two unit files conflict (like DMs
+  do, for example)
+
+* add "systemctl start -v foobar.service" that shows logs of a service
+  while the start command runs. This is non-trivial to do without
+  races though, since we should flush out all journal messages before
+  returning from the "systemctl stop".
+
+* systemctl: if some operation fails, show log output?
+
+* Add a new verb "systemctl top"
+
+* unit install:
+  - "systemctl mask" should find all names by which a unit is accessible
+    (i.e. by scanning for symlinks to it) and link them all to /dev/null
+
+* nspawn:
+  - emulate /dev/kmsg using CUSE and turn off the syslog syscall
+    with seccomp. That should provide us with a useful log buffer that
+    systemd can log to during early boot, and disconnect container logs
+    from the kernel's logs.
+  - as soon as networkd has a bus interface, hook up --network-interface=,
+    --network-bridge= with networkd, to trigger netdev creation should an
+    interface be missing
+  - a nice way to boot up without machine id set, so that it is set at boot
+    automatically for supporting --ephemeral. Maybe hash the host machine id
+    together with the machine name to generate the machine id for the container
+  - fix logic always print a final newline on output.
+    https://github.com/systemd/systemd/pull/272#issuecomment-113153176
+  - should optionally support receiving WATCHDOG=1 messages from its payload
+    PID 1...
+  - optionally automatically add FORWARD rules to iptables whenever nspawn is
+    running, remove them when shut down.
+  - add support for sysext extensions, too. i.e. a new --extension= switch that
+    takes one or more arguments, and applies the extensions already during
+    startup.
+  - when main nspawn supervisor process gets suspended due to SIGSTOP/SIGTTOU
+    or so, freeze the payload too.
+  - support time namespaces
+  - on cgroupsv1 issue cgroup empty handler process based on host events, so
+    that we make cgroup agent logic safe
+  - add API to invoke binary in container, then use that as fallback in
+    "machinectl shell"
+  - make nspawn suitable for shell pipelines: instead of triggering a hangup
+    when input is finished, send ^D, which synthesizes an EOF. Then wait for
+    hangup or ^D before passing on the EOF.
+  - greater control over selinux label?
+  - support that /proc, /sys/, /dev are pre-mounted
+  - maybe allow TPM passthrough, backed by swtpm, and measure --image= hash
+    into its PCR 11, so that nspawn instances can be TPM enabled, and partake
+    in measurements/remote attestation and such. swtpm would run outside of
+    control of container, and ideally would itself bind its encryption keys to
+    host TPM.
+  - make boot assessment do something sensible in a container. i.e send an
+    sd_notify() from payload to container manager once boot-up is completed
+    successfully, and use that in nspawn for dealing with boot counting,
+    implemented in the partition table labels and directory names.
+  - optionally set up nftables/iptables routes that forward UDP/TCP traffic on
+    port 53 to resolved stub 127.0.0.54
+  - maybe optionally insert .nspawn file as GPT partition into images, so that
+    such container images are entirely stand-alone and can be updated as one.
+  - The subreaper logic we currently have seems overly complex. We should
+    investigate whether creating the inner child with CLONE_PARENT isn't better.
+  - Reduce the number of sockets that are currently in use and just rely on one
+    or two sockets.
+  - Support running nspawn as an unprivileged user.
+
+* machined: add API to acquire UID range. add API to mount/dissect loopback
+  file. Both protected by PK. Then make nspawn use these APIs to run
+  unprivileged containers. i.e. push the truly privileged bits into machined,
+  so that the client side can remain entirely unprivileged, with SUID or
+  anything like that.
+
+* machined:
+  - add an API so that libvirt-lxc can inform us about network interfaces being
+    removed or added to an existing machine
+  - "machinectl migrate" or similar to copy a container from or to a
+    difference host, via ssh
+  - introduce systemd-nspawn-ephemeral@.service, and hook it into
+    "machinectl start" with a new --ephemeral switch
+  - "machinectl status" should also show internal logs of the container in
+    question
+  - "machinectl history"
+  - "machinectl diff"
+  - "machinectl commit" that takes a writable snapshot of a tree, invokes a
+    shell in it, and marks it read-only after use
+
+* udev:
+  - move to LGPL
+  - kill scsi_id
+  - add trigger --subsystem-match=usb/usb_device device
+  - reimport udev db after MOVE events for devices without dev_t
+  - re-enable ProtectClock= once only cgroupsv2 is supported.
+    See f562abe2963bad241d34e0b308e48cf114672c84.
+
+* coredump:
+  - save coredump in Windows/Mozilla minidump format
+  - when truncating coredumps, also log the full size that the process had, and make a metadata field so we can report truncated coredumps
+  - add examples for other distros in ELF_PACKAGE_METADATA
+
+* support crash reporting operation modes (https://live.gnome.org/GnomeOS/Design/Whiteboards/ProblemReporting)
+
+* tmpfiles:
+  - apply "x" on "D" too (see patch from William Douglas)
+  - allow time-based cleanup in r and R too
+  - instead of ignoring unknown fields, reject them.
+  - creating new directories/subvolumes/fifos/device nodes
+    should not follow symlinks. None of the other adjustment or creation
+    calls follow symlinks.
+  - add --test mode
+  - teach tmpfiles.d q/Q logic something sensible in the context of XFS/ext4
+    project quota
+  - teach tmpfiles.d m/M to move / atomic move + symlink old -> new
+  - add new line type for setting btrfs subvolume attributes (i.e. rw/ro)
+  - tmpfiles: add new line type for setting fcaps
+
+* udev-link-config:
+   - Make sure ID_PATH is always exported and complete for
+     network devices where possible, so we can safely rely
+     on Path= matching
+
+* sd-rtnl:
+   - add support for more attribute types
+   - inbuilt piping support (essentially degenerate async)? see loopback-setup.c and other places
+
+* networkd:
+   - add more keys to [Route] and [Address] sections
+   - add support for more DHCPv4 options (and, longer term, other kinds of dynamic config)
+   - add reduced [Link] support to .network files
+   - properly handle routerless dhcp leases
+   - work with non-Ethernet devices
+   - dhcp: do we allow configuring dhcp routes on interfaces that are not the one we got the dhcp info from?
+   - the DHCP lease data (such as NTP/DNS) is still made available when
+     a carrier is lost on a link. It should be removed instantly.
+   - expose in the API the following bits:
+         - option 15, domain name
+         - option 12, hostname and/or option 81, fqdn
+         - option 123, 144, geolocation
+         - option 252, configure http proxy (PAC/wpad)
+   - provide a way to define a per-network interface default metric value
+     for all routes to it. possibly a second default for DHCP routes.
+   - allow Name= to be specified repeatedly in the [Match] section. Maybe also
+     support Name=foo*|bar*|baz ?
+   - whenever uplink info changes, make DHCP server send out FORCERENEW
+
+* in networkd, when matching device types, fix up DEVTYPE rubbish the kernel passes to us
+
+* Figure out how to do unittests of networkd's state serialization
+
+* dhcp:
+   - figure out how much we can increase Maximum Message Size
+
+* dhcp6:
+   - add functions to set previously stored IPv6 addresses on startup and get
+     them at shutdown; store them in client->ia_na
+   - write more test cases
+   - implement reconfigure support, see 5.3., 15.11. and 22.20.
+   - implement support for temporary addresses (IA_TA)
+   - implement dhcpv6 authentication
+   - investigate the usefulness of Confirm messages; i.e. are there any
+     situations where the link changes without any loss in carrier detection
+     or interface down
+   - some servers don't do rapid commit without a filled in IA_NA, verify
+     this behavior
+   - RouteTable= ?
+
+* shared/wall: Once more programs are taught to prefer sd-login over utmp,
+  switch the default wall implementation to wall_logind
+  (https://github.com/systemd/systemd/pull/29051#issuecomment-1704917074)