set a default one in mkhelper.cfg

Signed-off-by: Leah Rowe <leah@libreboot.org>

Never, ever build images where GRUB is the primary payload.

These options have been removed from target.cfg handling:

* seabios_withgrub
* grub_withseabios

The "payload_grub" variable now does the same thing as
the old "seabios_withgrub" variable, if set.

The "grubonly" configuration is retained, and enabled by
default when SeaGRUB is enabled (non-grubonly also available).

Due to lbmk issue #216, it is no longer Libreboot policy to
make GRUB the primary payload on any board. GRUB's sheer size
and complexity, plus the large number of memory corruption issues
similar to it that *have* been fixed over the years, tells me
that GRUB is a liability when it is the primary payload.

SeaBIOS is a much safer payload to run as primary, on x86, due
to its smaller size and much more conservative development; it
is simply far less likely to break.

If GRUB breaks in the future, the user's machine is not
bricked. This is because SeaBIOS is the default payload.

Since I no longer wish to ever provide GRUB as a primary
payload, supporting it in lbmk adds needless bloat that
will later probably break anyway due to lack of testing,
so let's just assume SeaGRUB in all cases where the user
wants to use a GRUB payload.

You can mitigate potential security issues with SeaBIOS
by disabling option ROM execution, which can be done at
runtime by inserting integers into CBFS. The SeaBIOS
documentation says how to do this.

Libreboot's GRUB hardening guide still says how to add
a bootorder file in CBFS, making SeaBIOS only load GRUB
from CBFS, and nothing else. This, combined with the
disablement of option ROM execution (if using Intel
graphics), pretty much provides the same security benefits
as GRUB-as-primary, for example when setting a GRUB password
and GPG checks, with encrypted /boot as in the hardening guide.

Signed-off-by: Leah Rowe <leah@libreboot.org>

the background is only a few kb. the whole rationale
before was to limit the space used in memdisk, but this
decision was made when the background was much bigger;
it has since been optimised greatly, and the grub modules
were heavily reduce, so it should be safe.

grub's memdisk breaks when you add too much data to it.
as part of simplifying the rest of lbmk, this change removes
some more bloat from the rest of lbmk. handling this in the
memdisk is much simpler than handling it with cbfstool.

Signed-off-by: Leah Rowe <leah@libreboot.org>

Signed-off-by: Leah Rowe <leah@libreboot.org>

A subsequest revision will set them again as needed,
per coreboot target.

Signed-off-by: Leah Rowe <leah@libreboot.org>

See:
https://codeberg.org/libreboot/lbmk/issues/216

Almost all users will be OK running GRUB, but a
minority of users have experienced a fatal error
pertaining to grub_free() or grub_realloc() (as
my investigation of GRUB sources reveal when grepping
the error reported in the link above).

We don't yet know what the bug is, only that the
error occurs, leading to an effective brick if the
user has GRUB as their primary payload.

So far, it has only been reported on some Intel
SandyBridge-based Dell Latitudes in Libreboot, but
we can't be too sure.

The user reported that memtest86+ passes just fine,
and SeaBIOS works; BIOS GRUB also works, which means
that the bug is likely only in an area of GRUB that
runs specifically on the coreboot payload, so it's
probably a driver in GRUB when running on the metal
rather than BIOS/UEFI.

The build system supports a configuration whereby
SeaBIOS is the primary payload, but GRUB is available
in the SeaBIOS boot select menu, and an additional
configuration is available where GRUB is what SeaBIOS
executes first (while still providing boot select);
both of these are now the *only* configurations
available, on all x86 targets except QEMU.

The QEMU target is fine because if the bug occurs there,
you can just close QEMU and try a different image.

Even after this bug is later identified and fixed,
the GRUB source code is vastly over-engineered and there
are likely many more such bugs. SeaBIOS is a reliable
payload; the code is small and robust. Remember always:

Code

equals

bugs

Therefore, this configuration change is likely going
to be permanent. This will apply in the next release.

Signed-off-by: Leah Rowe <leah@libreboot.org>

the release variable is all we need, turning a target on
or off for a given release.

the status checks were prone to bugs, and unnecessary; it
also broke certain benchmark scripts.

it's better to keep the lbmk logic simpler. board status
will be moved to the documentation instead.

Signed-off-by: Leah Rowe <leah@libreboot.org>

the previous issue was tested, and can no longer be reproduced

Signed-off-by: Leah Rowe <leah@libreboot.org>

Signed-off-by: Leah Rowe <leah@libreboot.org>

export LBMK_VERSION_TYPE=x
x can be: stable, unstable

in target.cfg files, specify:
status=x
x can be: stable, unstable, broken, untested
if unset, lbmk defaults to "unknown"

if LBMK_VERSION_TYPE is set, no confirmation is asked
if the given target matches what's set (but what's set
in that environmental variable can only be stable or
unstable)

if LBMK_RELEASE="y", no confirmation is asked, unless
the target is something other than stable/unstable

"unstable" means it works, but has a few non-breaking
bugs, e.g. broken s3 on dell e6400

whereas, if raminit regularly fails or it is so absolutely
unreliable as to be unusable, then the board should be
declared "broken"

untested means: it has not been tested

With this change, it should now be easier to track whether
a given board is tested, in preparation for releases. When
working on trees/boards, status can be set for targets.

Also: in the board directory, you can add a "warn.txt" file
which will display a message. For example, if a board has a
particular quirk to watch out for, write that there. The message
will be printed during the build process, to stdout.

If status is anything *other* than stable, or it is unstable
but LBMK_VERSION_TYPE is not set to "unstable", and not building
a release, a confirmation is passed.

If the board is not specified as stable or unstable, during
a release build, the build is skipped and the ROM is not
provided in that release; this is in *addition* to
release="n" or release="y" that can be set in target.cfg,
which will skip the release build for that target if "n"

Signed-off-by: Leah Rowe <leah@libreboot.org>