On Sat, 22 Feb 2020 17:39:03 +0000, Enzo Desiage said:

> I had a look back at the book and couldn't find the command
> 'make localmodconfig' in "The Linux Kernel  in a Nutshell" book,
> why is that? Was it introduced  in recent years?

Depends what you call "recent". Looks like v2.6.30-ish.

commit 03fa25da8335a942161a8070b3298cfd4edf9b6a
Author: Steven Rostedt <srostedt@redhat.com>
Date:   Wed Apr 29 22:52:22 2009 -0400

    kconfig: make localmodconfig to run streamline_config.pl
    
    Running the streamline_config.pl script manually can still be confusing
    for some users. This patch adds the localmodconfig option. This will
    automatically run streamline_config.pl on the current .config and
    then run "make silentoldconfig" to fix any wholes that might have been
    created.
    
     $ make localmodconfig
    
    This will remove any module configurations in .config that are not needed
    to compile the modules that are loaded.
    
    Signed-off-by: Steven Rostedt <rostedt@goodmis.org>