Now that the necessary functions from log.h have been moved to macro.h,
we can stop including log.h in macro.h. This requires modifying source
files all over the tree to include log.h instead.
The glibc API is behind the wrapper is called "secure_getenv()", hence
our wrapper really should keep the order too, otherwise things are just
too confusing.
in_initrd() was really doing two things: checking if we're in the initrd, and
also verifying that the initrd is set up correctly. But this second check is
complicated, in particular it would return false for overlayfs, even with an
upper tmpfs layer. It also doesn't support the use case of having an initial
initrd with tmpfs, and then transitioning into an intermediate initrd that is
e.g. a DDI, i.e. a filesystem possibly with verity arranged as a disk image.
We don't need to check if we're in initrd in every program. Instead, concerns
are separated:
- in_initrd() just does a simple check for /etc/initrd-release.
- When doing cleanup, pid1 checks if it's on a tmpfs before starting to wipe
the old root. The only case where we want to remove the old root is when
we're on a plain tempory filesystem. With an overlay, we'd be creating
whiteout files, which is not very useful. (*)
This should resolve https://bugzilla.redhat.com/show_bug.cgi?id=2137631
which is caused by systemd refusing to treat the system as an initrd because
overlayfs is used.
(*) I think the idea of keeping the initrd fs around for shutdown is outdated.
We should just have a completely separate exitrd that is unpacked when we want
to shut down. This way, we don't waste memory at runtime, and we also don't
transition to a potentially older version of systemd. But we don't have support
for this yet.
This replaces 0fef5b0f0bd9ded1ae7bcb3e4e4b2893e36c51a6.
This reverts commit 1f22621ba3.
As described in the reverted commit, we don't want to get rid of the check
completely. But the check requires opting-in by setting SYSTEMD_IN_INITRD=lenient,
which is cumbersome and doesn't seem to actually happen.
https://bugzilla.redhat.com/show_bug.cgi?id=2137631 is caused by systemd refusing
to treat the system as an initrd because overlayfs is used. Let's revert this
approach and do something that doesn't require opt-in instead.
I don't think it makes sense to keep support for "SYSTEMD_IN_INITRD=lenient" or
"SYSTEMD_IN_INITRD=auto". To get "auto" behaviour, just unset the option. And
"lenient" will be reimplemented as a better check. Thus the changes to the
option interface are completely reverted.
I changed imports of util.h to initrd-util.h, or added an import of
initrd-util.h, to keep compilation working. It turns out that many files didn't
import util.h directly.
When viewing the patch, don't be confused by git rename detection logic:
a new .c file is added and two functions moved into it.
Daan De Meyer
Lennart Poettering
Zbigniew Jędrzejewski-Szmek