# best way of updating kernel config

## randal1

Hi All,

Below are the basic steps I use to upgrade my linux kernel:

 *Quote:*   

> 
> 
> How to upgrade a Gentoo Kernel (using Vanilla-Sources):
> 
> emerge required version of vanilla-sources
> ...

 

My problem is that I recently upgraded to 2.6.17-rc4 and things seemed to be working ok.  However, when I tried to add modular support for some package in my kernel - by running "genkernel --menuconfig all" - when I'm done and try to save the changes I see various error about:

 *Quote:*   

> 
> 
> ~ # genkernel --menuconfig all; lilo
> 
> * Gentoo Linux Genkernel; Version 3.3.5
> ...

 

Now I have a feeling im doing something wrong by using my old kernel configuration, but I don't know what it is that I am doing wrong!  Which is why I am posting here for advice  :Smile: 

Many thanks in advance

----------

## limn

Your procedure appears reasonable.

```
drivers/net/wireless/atmel.c:71:27: net/ieee80211.h: No such file or directory 
```

It is not finding a header file. Try

```
ls /usr/src/linux/include/net/ieee80211.h
```

----------

## mahler

I believe that the

"cp kernel-config-old kernel-config-new" 

is officially considered unsafe when changing kernel versions.

New kernel versions can rename and otherwise reorganize kernel options.

I actually have been doing it that way myself,

and got burned a litlle while ago, when the netfilter option names changed.

I ended up with a firewall free computer until I noticed,

since my old setting did not mean anything anymore  :Sad: .

There still outght to be a (semi)automatic way of porting an old config to a new kernel though.

The above problem seems to just be a kind of version controll issue,

cfg-update seems to solve most etc-update conflicts automatically without losing your customizations.

However, AFAIK, manual reconfiguration each time is the the recommended way,

but I would be happy to find out I am wrong about this.

Daniel

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## whig

I fetch, build and install my kernel manually. To upgrade my .config so it works with the new version of the kernel I do

```
make oldconfig
```

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## randal1

Thanks for all your replies....really appreciate the help.

Limn, I just followed your command and the file "/usr/src/linux/include/net/ieee80211.h" was not found.  Any ideas as to where I can find this?

Whig, is there any way I can use the "make oldconfig" command somewhere in my process?  I know that you do the process manually, but I'm not sure that I know enough to do this.

Cheers guys  :Smile: 

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## limn

Your 2.6.17-rc4 source files are incomplete. Something went awry there. Pull the full source from www.kernel.org/pub/linux/kernel/v2.6/testing/ and verify that the file exists before retrying with that source.

When genkernel ran

```
* >> Running oldconfig... 
```

it ran oldconfig automatically.

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## randal1

I did what you said, downloaded the tar file and checked that the file exists...it does :S

I don't have a clue what to do next, any recommendation you could make? Maybe a different kernel version, or use the downloaded tar file and reinstall?

Many thanks  :Smile: 

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## limn

If you specifically want 2.6.17-rc4, then yes, put the source into /usr/src and unpackage it, then make the link and have at it.

gentoo-sources may have caught up with that kernel version since your first post.

----------

