The code is given in accordance with the documentation
See-also: commit 2987fa8f

The parameter is used to save the intermediate tarball used to
build the virtual machine image.

So we are can to build compressed img files.

This is necessary for the 'rootfs' initrd feature to work properly

This is a standard set of initrd features.

This features not needed for auto-detect.
We also add features not only to initrd.mk, but also specify them
explicitly in the command.

While this argument can only have one "EFI" value.
Thus, the problem of building an image for Raspberry Pi on armh,
where there is no grub-efi, was solved.

For Raspberry Pi needed to build grub-efi + MBR images.

The entry in /etc/fstab about the mount parameters of the root
partition needs to be done not only for builds with u-boot.
But, if the record already exists, then it will not be added.
The file system type is set by the variable VM_FSTYPE.

Since packet sorting is enabled by default, then
the order in KFLAVORS has ceased to matter.
Kernels are always installed in alphabetical order.
Therefore, it makes no sense to sort by buildtime.
See-also: https://bugzilla.altlinux.org/show_bug.cgi?id=30806

Also fixed my typo. When creating a symlink, the variable
$kver was used, i.e. the entire list of kernels, not the
last value $KVER of the list.

tar2fs does not run in hasher and without qemu. This causes build
problems for an architecture other than the host.

Not used by systemd and looks obsolete generally
as sysvinit-based disk images aren't really targeting
low-resource systems these days _by default_ but rather
_can_ target those as well; feel free to reconstruct
these "RAM saving" bits as a part of e.g. lowmem patch.

The problem at hand is that different kernels can have
varying module sets, and it makes sense to put four of
those at once sometimes; so avoid silly build breakage.

recovery.tar needed for tavolga (mipsel).
This commit is the result of transferring the required functionality
from build-mr (mipsel rootfs).
This change uses external tool to build Tavolga-compatible
recovery.tar. This simplifies the logic and avoids having
recovery workdir in the profile.
After this change, m-p will require tavolga-image-tools >= 3.0.

KFLAVOURS can describe more than one kernel, get iterator back.

Fixes: 27674e29

(gkebfm@ thinks it was a terrible idea in the first place
and mike@ agrees; this is a rework TODO item)

build-vm ceases to be a target for building only virtual machine images.
Now it can be used to build tarballs designed for installation on real
machines.

This commit is the result of transferring the required functionality from
build-mr (mipsel rootfs) by Ivan Melnikov <iv@altlinux.org>.

NB: mike@ strongly objected to this dilution but gave up eventually;
    the whole kernel/build-vm/tar2fs/pack mess should be split into
    distinct layers busy with their own responsibilities:

    1) a tarball with kernel is done without tar2fs at all
       (and no build-vm bits should be needed either, maybe
       it's worth splitting and renaming as "vm" meaning
       disk image for some armh board is grossly misleading);

    2) a tarball with kernel can be further (multi-)packed
       as, well, (compressed) tarball and a disk image
       (only the latter one should employ build-vm/tar2fs);

    3) compression should be done in pack feature style,
       preferably described once and not duplicated all over
       the profile for every single new kind of its output.

    In the mean time, running into this and moving no further
    starts to hurt more than it could help.

NB: 07-kernel change breaks multi-kernel setup!

Breaks: 650e92bf

We should delete the tarball whenever it's not the target.

The original commit broke system tar2fs use by accidentally
moving TOPDIR definition into a separate shell execution;
thanks iv@ for spotting and fixing it promptly.
Co-authored-by: Ivan A. Melnikov" <iv@altlinux.org>

...if it's a systemd-based image; no real error then.

tar2fs comes from m-p, not from mkimage. Also, we should
use $TOPDIR from shell, not $(TOPDIR) from make, when
calling it.

Note: this is a security fix for environments relying
on packaged mkimage-profiles with sudo enabled for the
builder user.

Fixes: f293239d

This was crucial for e2k rescue image supporting
multiple CPU versions but can be useful elsewhere.

It has no VM hypervisor so far, the images are intended
for bare metal execution.

This is a fix to previous failures of
ve/vm + use/repo/main build attempts
(in fact, any non-distro/ targets).

SUBDIRS were just optimized away...

...so that it doesn't show up in a diff with build-vm.

This is a compressed version of good ol' qcow2.
Suggested-by: Alexey Shabalin <shaba@altlinux.org>

This isn't a warning cause, this is a error cause!

BASE_PACKAGES_REGEXP and THE_PACKAGES_REGEXP,
to be exact; the lack of handling these appears
to have been the culprit of firefox missing in
vm images which use/browser/firefox.

...and leave it for possible further investigation
only if debug level is 2 or higher (which is uncommon).

No need to deduce kernel version again,
just save it in a temporary file.

The main reason to change what worked is
that e2k kernel-image package has Linux bits
named as image-$kver and not vmlinuz-$kver;
the guessing logic taking all of this into
account resulted in non-aesthetic patch.

NB: there's a duplicating script within
    kernel feature; it wasn't easy to avoid
    this and it might differ when handling
    multiple kernels, I didn't think much
    about this now as vm images tend to ship
    with the sole one.

In this case it's rather worth it to examine build.log
than read documentation again (as vm.txt should have been
read or at least skimmed through to get sudo setup ready,
and the problem might be either an environment one or a bug).

It's at least removing the very obvious user->root
attack through (maliciously) modifying bin/tar2fs
and waiting for it to be run; if mkimage-profiles
is installed system-wide as a package, the script
from /usr/share/mkimage-profiles will be tried so
those willing to allow vm/* build to themselves
can provide for a passwordless sudo (as described
in doc/vm.txt) to run a root-only writable script,
not user-writable.

Still not perfect but a step away from the abyss.