Re: [gentoo-user] Using an old kernel .config as the basis for a new .config

[Rich Freeman <rich0@gentoo.org>]

On Thu, Dec 28, 2017 at 3:05 PM, Jack <ostroffjh@users.sourceforge.net> wrote:
>
> You need to copy your old .config into the new kernel source directory.
> "make oldconfig" then uses those values, and only asks you about new items.

It will find an existing config in /boot if you have one named using
the upstream naming convention (which happens if you install the
kernel using make install on a vanilla kernel - I'm not sure about
genkernel or gentoo-sources offhand).

If you have /proc/config.gz enabled then you can also do a zcat
/proc/config.gz > .config to extract your current config.  I always
enable /proc/config.gz since it costs a few kb tops and comes in handy
anytime you're not sure what config you're running (though if you
built some modules after the fact it might not be entirely current).

-- 
Rich