How do you generate the config file?

[Guru Das S]

On 29 January 2017 at 16:19, Abel <akronix5 at gmail.com> wrote:
> I've posted a mail with the screenshot (waiting for moderation) when I try
> to boot from make defconfig built kernel. Basically the kernel doesn't boot
> because "Missing modules (cat /proc/modules; ls /dev " it says...It's the
> same screen that appeared when I tried using make oldconfig pressing enter
> for default values.
>
> I tried using make localmodconfig but It again asks for many config params
> that I don't know anything about.
>
> Saludos,
>
>                                                        Abel.

Hi Abel,

The procedure I followed in order to compile, install and boot my
custom compiled kernel is:

1. Copy .config from existing distribution to kernel tree.

2. Run make localmodconfig (I also got a bunch of prompts for
parameters I had no idea about. I just pressed down Enter till the
stream of options stopped flowing!)

3. Run make -j<N> where N is a good number for your system.

4. Run make modules_install

5. Run make install (This ran update-grub for me at the end, though,
which was convenient)

That's it. I was able to boot into this newly compiled kernel via
grub's selection menu upon rebooting. I think you may have missed
doing Step 4 above.


Guru Das Srinagesh.


>
> On 30 January 2017 at 01:11, Abel <akronix5 at gmail.com> wrote:
>>
>> Hi.
>>
>> I just built using make defconfig and it, again, doesn't boot. Instead it
>> displays the error that I've described before (sorry I forgot to attach the
>> screenshot, I attach it here).
>>
>> As I already stated, neither /boot/${uname -r} nor make oldconfig work for
>> me, they both show the screen above.
>>
>> Saludos,
>>
>>                                                        Abel.
>>
>> On 30 January 2017 at 01:08, Guru Das S <gurooodas at gmail.com> wrote:
>>>
>>> On 29 January 2017 at 15:32, 慕冬亮 <mudongliangabcd at gmail.com> wrote:
>>> > Hello,
>>> >     If you want to reuse the config of current kernel, you can use
>>> > `make oldconfig` to generate config file.
>>> >
>>> > --
>>> > My best regards to you.
>>> >
>>> >      No System Is Safe!
>>> >      Dongliang Mu
>>> >
>>> > 2017-01-29 18:24 GMT-05:00 Ozgur Karatas <mueddib at goosey.org>:
>>> >>
>>> >> Hello,
>>> >>
>>> >> you can get .config files in two ways, firstly get the existing
>>> >> .config file
>>> >> and compile to kernel.
>>> >>
>>> >> $ cp /boot/config-x.x.x /bla/linux/.config
>>> >>
>>> >> Second, use the generate command:
>>> >>
>>> >> $ make defconfig
>>> >>
>>> >> Regards,
>>> >>
>>> >> ~Ozgur
>>> >>
>>> >> 30.01.2017, 01:18, "Abel" <akronix5 at gmail.com>:
>>> >>
>>> >> Hi!
>>> >>
>>> >> Where do you get the config file from? or do you generate it yourself?
>>> >>
>>> >> I'm using xUbuntu 16.04 in a VM inside VMWare, following the
>>> >> instructions
>>> >> described in kernelnewbies wiki. (By the way, the download links to
>>> >> the iso
>>> >> images of Ubuntu don't work for me)
>>> >>
>>> >> If I copy the latest config file in /boot, kernel 4.4.0, it starts to
>>> >> ask me
>>> >> many config parameters that I don't know what to answer. I tried to
>>> >> press
>>> >> always <enter> to set up the default parameters, but after compiling I
>>> >> get
>>> >> an error trying to boot from that kernel (see atachment).
>>> >>
>>> >> I tried with make menuconfig and that seems to work, but it takes too
>>> >> long
>>> >> because it builds and includes many many drivers modules.
>>> >> Yeah, I know I could navigate through the ncurses window and select
>>> >> the
>>> >> stuff I want and deselect what I don't want, but I'd rather prefer
>>> >> just a
>>> >> simple config file that builds and works and don't waste time in
>>> >> understanding all the stuff that it's in there.
>>> >>
>>> >> So, isn't there a way to get a simple config file just to develop
>>> >> kernel
>>> >> stuff for an Ubuntu image?
>>> >> I've even gone to the kernel ppa sources for Ubuntu:
>>> >> http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.9.5/; but it only
>>> >> provides
>>> >> a patch using the debian config files (which don't come from git
>>> >> sources of
>>> >> course).
>>> >>
>>> >> I just want a config file, copy it to the kernel root code and
>>> >> compile.
>>> >>
>>> >> Greetings,
>>> >>
>>> >>                                                        Abel
>>> >>
>>> >>
>>> >> _______________________________________________
>>> >> Kernelnewbies mailing list
>>> >> Kernelnewbies at kernelnewbies.org
>>> >> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>>> >>
>>> >
>>> > _______________________________________________
>>> > Kernelnewbies mailing list
>>> > Kernelnewbies at kernelnewbies.org
>>> > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>>>
>>> Hi Abel,
>>>
>>> To add to what Ozgur said, you may first copy the existing .config
>>> file that comes along with your Linux distribution to your kernel
>>> tree, and then use:
>>>
>>> $ make localmodconfig
>>>
>>> instead of defconfig. A quick Google search should tell you the
>>> differences between the two - and from what I've read, localmodconfig
>>> is preferred to defconfig.
>>>
>>> Hope this helps.
>>>
>>>
>>> Guru Das Srinagesh.
>>
>>
>