The kernel-config.py script takes a toml file containing a set of
kernel configuration key-value pairs. Then it parses the Kconfig files
in a kernel source tree and render the given configuration as a
LFS-style <screen> in a separate XML file. The XML file can be used in
the book with xinclude.
Some "features":
1. The lines are limited to 80 columns.
If the text of the configuration option is too long, it will be
trimmed; if the symbolic name of the option cannot fit in this line,
a separate line will be used for it.
2. If a configuration option is given but it does not exist in Kconfig
files, the script will abort immediately. This helps catching
removed options.
3. The script also aborts immediately if a configuration option is
illegal, for example setting an option to 'M' while it cannot be a
module.
4. The infrastructure is not wired into the main Makefile. It's because
not all editors have the latest kernel tree, and even if they do the
locations of the kernel tree are still different. To update the
generated XML files, use
"make -C kernel-config KERNEL_TREE=/sources/linux-x.y.z".
Backword incompatible change:
The script no longer outputs "CONFIG_" prefix for the symbolic name. It
really does not make too much sense to waste 7 characters here because
it's a common prefix for all options!
A limitation:
The script does not really validate the configuration. Generally
validating the configuration requires to solve the 3-CNF-SAT problem,
which is NP-complete.
The issue is a new regression in 0.25.0, and it's causing test failures
in glib-networking and libsoup.
We know we are on Linux so we don't need the fancy #ifdef stuff, so we
can simplify the change into a sed.
1. Move the configuration file into /etc, to be consistent with other
configuration files created in BLFS.
2. We no longer need a separate "configure the graphic card" example
because the TearFree configuration file is already a good example.
3. Tearing issue is really not new after xf86-video-* removal. In some
xf86-video-* drivers a TearFree option is available but rarely
enabled by default (only the amdgpu driver when the output is rotated
or transformed). So this is actually the first time we document it
in BLFS.
4. It's really not difficult to observer the tearing by dragging a
window in twm, despite twm only renders the window border during
dragging.
With modesetting driver, $HOME/.local/share/xorg/Xorg.0.log contains:
[ 65817.713] (II) AIGLX: Loaded and initialized crocus
And there is no more "AIGLX error" messages.
I really don't understand what it is for. And I can run twm without it.
If someone has a good reason to use legacy fonts, please revert, but you
should at least consider marking it runtime and maybe demoting it to
optional.
I'm pretty sure it's at least not "required": there are some
configurations running qemu "headless".
And it seems qemu does not refers to any X components directly. It uses
X through SDL or GTK3, and they are already in the dependencies.
