• Paolo 'Blaisorblade' Giarrusso's avatar
    [PATCH] uml: use DEFCONFIG_LIST to avoid reading host's config · b2670eac
    Paolo 'Blaisorblade' Giarrusso authored
    This should make sure that, for UML, host's configuration files are not
    considered, which avoids various pains to the user.  Our dependency are such
    that the obtained Kconfig will be valid and will lead to successful
    compilation - however they cannot prevent an user from disabling any boot
    device, and if an option is not set in the read .config (say
    /boot/config-XXX), with make menuconfig ARCH=um, it is not set.  This always
    disables UBD and all console I/O channels, which leads to non-working UML
    kernels, so this bothers users - especially now, since it will happen on
    almost every machine (/boot/config-`uname -r` exists almost on every machine).
     It can be workarounded with make defconfig ARCH=um, but it is non-obvious and
    can be avoided, so please _do_ merge this patch.
    
    Given the existence of options, it could be interesting to implement
    (additionally) "option required" - with it, Kconfig will refuse reading a
    .config file (from wherever it comes) if the given option is not set.  With
    this, one could mark with it the option characteristic of the given
    architecture (it was an old proposal of Roman Zippel, when I pointed out our
    problem):
    
    config UML
    	option required
    	default y
    
    However this should be further discussed:
    *) for x86, it must support constructs like:
    
    ==arch/i386/Kconfig==
    config 64BIT
    	option required
    	default n
    where Kconfig must require that CONFIG_64BIT is disabled or not present in the
    read .config.
    
    *) do we want to do such checks only for the starting defconfig or also for
       .config? Which leads to:
    *) I may want to port a x86_64 .config to x86 and viceversa, or even among more
       different archs. Should that be allowed, and in which measure (the user may
       force skipping the check for a .config or it is only given a warning by
       default)?
    
    Cc: Roman Zippel <zippel@linux-m68k.org>
    Cc: <kbuild-devel@lists.sourceforge.net>
    Signed-off-by: default avatarPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
    Cc: Jeff Dike <jdike@addtoit.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    b2670eac
Kconfig 18.9 KB