poll() sets POLLNVAL inside of the poll structures if an invalid fd is
passed. So far we generally didn't check for that, thus not taking
notice of the error. Given that this specific kind of error is generally
indication of a programming error, and given that our code is embedded
into our projects via NSS or because people link against our library,
let's explicitly check for this and convert it to EBADF.
(I ran into a busy loop because of this missing check when some of my
test code accidentally closed an fd it shouldn't close, so this is a
real thing)
In the past we occasionally stumbled upon a build issue which could be
reproduced only with specific optimization level or other compilation
option. Let's try to build the current revision with several most common
compiler options causing such issues to catch them early.
Let systemd load a set of pre-compiled AppArmor profile files from a policy
cache at /etc/apparmor/earlypolicy. Maintenance of that policy cache must be
done outside of systemd.
After successfully loading the profiles systemd will attempt to change to a
profile named systemd.
If systemd is already confined in a profile, it will not load any profile files
and will not attempt to change it's profile.
If anything goes wrong, systemd will only log failures. It will not fail to
start.
Arch recently upgraded systemd to 245.6. Shortly afterwards, users began
reporting[0] that systemd detected an ordering cycle, and they were
unable to log in. The reason they were unable to log in was because of
ordering cycle resolution:
[...]
systemd[1]: sysinit.target: Job systemd-tmpfiles-setup.service/start deleted to break ordering cycle starting with sysinit.target/start
systemd[1]: sysinit.target: Job systemd-update-done.service/start deleted to break ordering cycle starting with sysinit.target/start
systemd[1]: sysinit.target: Job systemd-journal-catalog-update.service/start deleted to break ordering cycle starting with sysinit.target/start
systemd[1]: sysinit.target: Job local-fs.target/start deleted to break ordering cycle starting with sysinit.target/start
systemd[1]: sysinit.target: Job systemd-tmpfiles-setup.service/start deleted to break ordering cycle starting with sysinit.target/start
[...]
Whether the resolution did the right thing here or not is a longer-term
discussion, but in the interim we should at least make this distinction
between automount dependencies and mount dependencies clearer in the
documentation, so that users and distribution maintainers know what's
acceptable. In this case Arch actually backed out b3d7aef5 entirely and
released a new version due to the confusion.
Also see https://github.com/systemd/systemd-stable/issues/69.
0: https://bugs.archlinux.org/task/66908
On systemd systems we generally don't need to chdir() to root, we don't
need to setup /dev/ ourselves (as PID 1 does that during earliest boot),
and we don't need to set the OOM adjustment values, as that's done via
unit files.
Hence, drop this. if people want to use udev from other init systems
they should do this on their own, I am very sure it's a good thing to do
it from outside of udevd, so that fewer privileges are required by udevd. In
particular the dev_setup() stuff is something that people who build
their own non-systemd distros want to set up themselves anyway, in
particular as they already have to mount devtmpfs themselves anyway.
Note that this only drops stuff that isn't really necessary for testing
stuff, i.e. process properties and settings that don't matter if you
quickly want to invoke udev from a terminal session to test something.
dm-verity support in dissect-image at the moment is restricted to GPT
volumes.
If the image a single-filesystem type without a partition table (eg: squashfs)
and a roothash/verity file are passed, set the verity flag and mark as
read-only.
The usual behaviour when a timeout expires is to terminate/kill the
service. This is what user usually want in production systems. To debug
services that fail to start/stop (especially sporadic failures) it
might be necessary to trigger the watchdog machinery and write core
dumps, though. Likewise, it is usually just a waste of time to
gracefully stop a stuck service. Instead it might save time to go
directly into kill mode.
This commit adds two new options to services: TimeoutStartFailureMode=
and TimeoutStopFailureMode=. Both take the same values and tweak the
behavior of systemd when a start/stop timeout expires:
* 'terminate': is the default behaviour as it has always been,
* 'abort': triggers the watchdog machinery and will send SIGABRT
(unless WatchdogSignal was changed) and
* 'kill' will directly send SIGKILL.
To handle the stop failure mode in stop-post state too a new
final-watchdog state needs to be introduced.
Single filesystem images are mounted from the /dev/block/X:Y symlink
rather than /dev/loopZ, so we need to wait for udev to create it or
mounting will be racy and occasionally fail.
After today's Arch Linux image update, there seems to be a slight change
in delay reporting which breaks some asserts in
systemd-networkd-tests.py:
Expected:
limit 100 delay 50.0ms 10.0ms loss 20%
Current:
limit 100 delay 50ms 10ms loss 20%