This adds a new safe_fork() wrapper around fork() and makes use of it
everywhere. The new wrapper does a couple of things we previously did
manually and separately in a safer, more correct and automatic way:
1. Optionally resets signal handlers/mask in the child
2. Sets a name on all processes we fork off right after forking off (and
the patch assigns useful names for all processes we fork off now,
following a systematic naming scheme: always enclosed in () – in order
to indicate that these are not proper, exec()ed processes, but only
forked off children, and if the process is long-running with only our
own code, without execve()'ing something else, it gets am "sd-" prefix.)
3. Optionally closes all file descriptors in the child
4. Optionally sets a PR_SET_DEATHSIG to SIGTERM in the child, in a safe
way so that the parent dying before this happens being handled
safely.
5. Optionally reopens the logs
6. Optionally connects stdin/stdout/stderr to /dev/null
7. Debug logs about the forked off processes.
In similar fashion to the previous change, sync() operations can stall
endlessly if cache is unable to be written out. In order to avoid an
unbounded hang, the sync takes place within a child process. Every 10
seconds (SYNC_TIMEOUT_USEC), the value of /proc/meminfo "Dirty" is checked
to verify it is smaller than the last iteration. If the sync is not making
progress for 3 successive iterations (SYNC_PROGRESS_ATTEMPTS), a SIGKILL is
sent to the sync process and the shutdown continues.
This option allows a device path to be specified for the systemd
watchdog (both runtime and shutdown).
If a system requires a watchdog other than /dev/watchdog (pointing to
/dev/watchdog0) to be used to reboot the system, this setting should be
changed to the relevant watchdog device path (e.g. /dev/watchdog1).
This moves pretty much all uses of getpid() over to getpid_raw(). I
didn't specifically check whether the optimization is worth it for each
replacement, but in order to keep things simple and systematic I
switched over everything at once.
$ reboot -f
Failed to read reboot parameter file: No such file or directory
It seems that the warning on ENOENT was inadvertently introduced in
27c06cb516.
The warning reported in #5646 comes from systemctl, but let's fix the other
call site in the same way too.
Fixes#5646.
The output of processes can be gathered, and passed back to the callee.
(This commit just implements the basic functionality and tests.)
After the preparation in previous commits, the change in functionality is
relatively simple. For coding convenience, alarm is prepared *before* any
children are executed, and not before. This shouldn't matter usually, since
just forking of the children should be pretty quick. One could also argue that
this is more correct, because we will also catch the case when (for whatever
reason), forking itself is slow.
Three callback functions and three levels of serialization are used:
- from individual generator processes to the generator forker
- from the forker back to the main process
- deserialization in the main process
v2:
- replace an structure with an indexed array of callbacks
Always warn if something fails, and clarify that the involved utility functions
do so in their name.
Drop the REBOOT_PARAM_FILE macro. We don't do this for other flag file paths
like this, so don't do this for this one either. The path isn't configurable
anyway, hence let's make this easier to read by avoiding this one indirection.
There are more than enough calls doing string manipulations to deserve
its own files, hence do something about it.
This patch also sorts the #include blocks of all files that needed to be
updated, according to the sorting suggestions from CODING_STYLE. Since
pretty much every file needs our string manipulation functions this
effectively means that most files have sorted #include blocks now.
Also touches a few unrelated include files.
This introduces a new systemd.crash_reboot=1 kernel command line option
that triggers a reboot after crashing.
This also cleans up crash VT handling. Specifically, it cleans up the
configuration setting, to be between 1..63 or a boolean. This is to
replace the previous logic where "-1" meant disabled. We continue to
accept that setting, but only document the boolean syntax instead.
This also brings the documentation of the default settings in sync with
what actually happens.
The CrashChVT= configuration file setting is renamed to CrashChangeVT=,
following our usual logic of not abbreviating unnecessarily. The old
setting stays support for compat reasons.
Fixes#1300
When a systemd service running in a container exits with a non-zero
code, it can be useful to terminate the container immediately and get
the exit code back to the host, when systemd-nspawn returns. This was
not possible to do. This patch adds the following to make it possible:
- Add a read-only "ExitCode" property on PID 1's "Manager" bus object.
By default, it is 0 so the behaviour stays the same as previously.
- Add a method "SetExitCode" on the same object. The method fails when
called on baremetal: it is only allowed in containers or in user
session.
- Add support in systemctl to call "systemctl exit 42". It reuses the
existing code for user session.
- Add exit.target and systemd-exit.service to the system instance.
- Change main() to actually call systemd-shutdown to exit() with the
correct value.
- Add verb 'exit' in systemd-shutdown with parameter --exit-code
- Update systemctl manpage.
I used the following to test it:
| $ sudo rkt --debug --insecure-skip-verify run \
| --mds-register=false --local docker://busybox \
| --exec=/bin/chroot -- /proc/1/root \
| systemctl --force exit 42
| ...
| Container rkt-895a0cba-5c66-4fa5-831c-e3f8ddc5810d failed with error code 42.
| $ echo $?
| 42
Fixes https://github.com/systemd/systemd/issues/1290
Turns this:
r = -errno;
log_error_errno(errno, "foo");
into this:
r = log_error_errno(errno, "foo");
and this:
r = log_error_errno(errno, "foo");
return r;
into this:
return log_error_errno(errno, "foo");
Introduce a proper enum, and don't pass around string ids anymore. This
simplifies things quite a bit, and makes virtualization detection more
similar to architecture detection.
This patch removes includes that are not used. The removals were found with
include-what-you-use which checks if any of the symbols from a header is
in use.
Sometimes it is necessary to stop a generator from running. Either
because of a bug, or for testing, or some other reason. The only way
to do that would be to rename or chmod the generator binary, which is
inconvenient and does not survive upgrades. Allow masking and
overriding generators similarly to units and other configuration
files.
For the systemd instance, masking would be more common, rather than
overriding generators. For the user instances, it may also be useful
for users to have generators in $XDG_CONFIG_HOME to augment or
override system-wide generators.
Directories are searched according to the usual scheme (/usr/lib,
/usr/local/lib, /run, /etc), and files with the same name in higher
priority directories override files with the same name in lower
priority directories. Empty files and links to /dev/null mask a given
name.
https://bugs.freedesktop.org/show_bug.cgi?id=87230
Remove the optional sepearate opening of the directory,
it would be just too complicated with the change to
multiple directories.
Move the middle of execute_directory() to a seperate
function to make it easier to grok.
If the format string contains %m, clearly errno must have a meaningful
value, so we might as well use log_*_errno to have ERRNO= logged.
Using:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\((".*%m.*")/log_\1_errno(errno, \2/'
Plus some whitespace, linewrap, and indent adjustments.
As a followup to 086891e5c1 "log: add an "error" parameter to all
low-level logging calls and intrdouce log_error_errno() as log calls
that take error numbers", use sed to convert the simple cases to use
the new macros:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\("(.*)%s"(.*), strerror\(-([a-zA-Z_]+)\)\);/log_\1_errno(-\4, "\2%m"\3);/'
Multi-line log_*() invocations are not covered.
And we also should add log_unit_*_errno().
This adds a new log_emergency() function, which is equivalent to
log_error() for non-PID-1, and logs at the highest priority for PID 1.
Some messages which occur before freezing are converted to use it.
Our initrd interface specifies that the verb is in argv[1].
This is where systemd passes it to systemd-shutdown, but getopt
permutes argv[]. This confuses dracut's shutdown script:
Shutdown called with argument '--log-level'. Rebooting!
getopt can be convinced to not permute argv[] by having '-' as the first
character of optstring. Let's use it. This requires changing the way
non-option arguments (in our case, the verb) are processed.
This fixes a bug where the system would reboot instead of powering off.
If we run in the container then we run in a mount namespace. If namespace dies
then kernel should do unmounting for us, hence we skip unmounting in containers.
Also, it may be the case that we no longer have capability to do umount,
because we are running in the unprivileged container.
See: http://lists.freedesktop.org/archives/systemd-devel/2014-October/023536.html
Since commit b1e90ec515 systemd passes
its log settings to systemd-shutdown via command line parameters.
However, systemd-shutdown doesn't pass these parameters to
/run/initramfs/shutdown, causing it to fall back to the default log
settings.
This fixes the following bugs about the shutdown not being quiet
despite "quiet" being in the kernel parameters:
https://bugs.freedesktop.org/show_bug.cgi?id=79582https://bugs.freedesktop.org/show_bug.cgi?id=57216
getopt is usually good at printing out a nice error message when
commandline options are invalid. It distinguishes between an unknown
option and a known option with a missing arg. It is better to let it
do its job and not use opterr=0 unless we actually want to suppress
messages. So remove opterr=0 in the few places where it wasn't really
useful.
When an error in options is encountered, we should not print a lengthy
help() and overwhelm the user, when we know precisely what is wrong
with the commandline. In addition, since help() prints to stdout, it
should not be used except when requested with -h or --help.
Also, simplify things here and there.
As Zbigniew pointed out a new ConditionFirstBoot= appears like the nicer
way to hook in systemd-firstboot.service on first boots (those with /etc
unpopulated), so let's do this, and get rid of the generator again.
A new tool "systemd-firstboot" can be used either interactively on boot,
where it will query basic locale, timezone, hostname, root password
information and set it. Or it can be used non-interactively from the
command line when prepareing disk images for booting. When used
non-inertactively the tool can either copy settings from the host, or
take settings on the command line.
$ systemd-firstboot --root=/path/to/my/new/root --copy-locale --copy-root-password --hostname=waldi
The tool will be automatically invoked (interactively) now on first boot
if /etc is found unpopulated.
This also creates the infrastructure for generators to be notified via
an environment variable whether they are running on the first boot, or
not.
When running in 'quiet' mode, the only message printed from shutdown
binary would be 'Cannot finalize remaining file systems and devices,
giving up.', the only log line at error level before switch back to
initramfs. This is misleading, because in initramfs everything will
be cleaned up properly.
Avoid printing anything at error level before the attempt to switch
back to initramfs. Rework the messages to contain a bit more
information what is still remaining, to help people diagnose shutdown
issues.
If PID 1 debug logging is enabled, it is nice to keep those settings
when switching to systemd-shutdown binary, independently of whether
this was done through /proc/cmdline options, or through runtime
manipulations.
