[yocto] how the &^$%^%@%^#$ does "file://defconfig" work?

[Robert P. J. Day]

On Wed, 24 Apr 2013, Bruce Ashfield wrote:

> On 13-04-24 07:50 AM, Robert P. J. Day wrote:
> >
> >    been fighting with this for a couple of hours, so i'll start with
> > the short version -- here's the current explanation for "Changing the
> > Configuration" of your kernel:
> >
> > http://www.yoctoproject.org/docs/latest/kernel-dev/kernel-dev.html#changing-the-configuration
> >
> >    the salient bit:
> >
> > "If you have a complete Linux kernel .config file you want to use,
> > copy it to a directory named files, which must be in your layer's
> > recipes-kernel/linux directory, and name the file "defconfig"."
> >
> >    first, that clearly suggests that file://defconfig is to be used
> > *only* when you have a complete .config file you want to use, which
> > also implies that if you use that, you should not be picking up any
> > other snippets. that's how i read that -- the use of
> > "file://defconfig" means that that is *exactly* the final form of my
> > eventual .config file. if that's not true, then that wording needs to
> > change.
> >
> >    also, i've been trying to do just that for a couple hours now, and i
> > am definitely *not* getting that as my final .config file used for the
> > kernel configuration. so what should be happening here? thanks.
>
> What sort of delta are you seeing ? Just because something is a
> defconfig, doesn't mean that will be exactly what you see in the final
> .config.
>
> It also could vary a bit based on the kernel recipe you are using,
> i.e. if there are configure prepends or appends, or any input
> conditioning.
>
> The kernel's configuration routines will take all that input and
> potentially select, deselect or take defaults for values that are
> not in the defconfig .. hence why you'll see a delta.

  i'm starting to follow the logic, i think it's just the wording in
that section that needs tweaking. or maybe i just didn't get enough
sleep ...

rday

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
========================================================================