KBUILD tries to make initramfs contents :-)

KBUILD tries to make initramfs contents :-)

[Krzysztof Halasa]

Hi,

I'm a bit surprised :-)

I'm using a file list for initramfs generation. It's something like:

file /sbin/udev /usr/local/i386/build/udev/udev 0555 0 0
file /sbin/udevd /usr/local/i386/build/udev/udevd 0555 0 0
...

/usr/local/i386/build/udev directory contains full udev sources, not
just the executables.

Now "make linux" wants to rebuild udev executables, using kernel
build rules :-)

All details are of course available on request if needed.

This is 2.6.17, I haven't checked it but I think the change to
usr/Makefile which causes this is:

commit d39a206bc35d46a3b2eb98cd4f34e340d5e56a50
Author: Sam Ravnborg <sam@mars.ravnborg.org>
Date:   Tue Apr 11 13:24:32 2006 +0200

    kbuild: rebuild initramfs if content of initramfs changes
    
    initramfs.cpio.gz being build in usr/ and included in the
    kernel was not rebuild when the included files changed.
    
    To fix this the following was done:
    - let gen_initramfs.sh generate a list of files and directories included
      in the initramfs
    - gen_initramfs generate the gzipped cpio archive so we could simplify
      the kbuild file (Makefile)
    - utilising the kbuild infrastructure so when uid/gid root mapping changes
      the initramfs will be rebuild
    
    With this change we have a much more robust initramfs generation.


Should it stay this way or is it a bug?
-- 
Krzysztof Halasa

Re: KBUILD tries to make initramfs contents :-)

[Sam Ravnborg]

On Tue, Jun 27, 2006 at 03:06:20PM +0200, Krzysztof Halasa wrote:
> Hi,
> 
> I'm a bit surprised :-)
> 
> I'm using a file list for initramfs generation. It's something like:
> 
> file /sbin/udev /usr/local/i386/build/udev/udev 0555 0 0
> file /sbin/udevd /usr/local/i386/build/udev/udevd 0555 0 0
> ...
> 
> /usr/local/i386/build/udev directory contains full udev sources, not
> just the executables.
> 
> Now "make linux" wants to rebuild udev executables, using kernel
> build rules :-)
> 
> All details are of course available on request if needed.
> 
> This is 2.6.17, I haven't checked it but I think the change to
> usr/Makefile which causes this is:
> 
> commit d39a206bc35d46a3b2eb98cd4f34e340d5e56a50
> Author: Sam Ravnborg <sam@mars.ravnborg.org>
> Date:   Tue Apr 11 13:24:32 2006 +0200
> 
>     kbuild: rebuild initramfs if content of initramfs changes
>     
>     initramfs.cpio.gz being build in usr/ and included in the
>     kernel was not rebuild when the included files changed.
>     
>     To fix this the following was done:
>     - let gen_initramfs.sh generate a list of files and directories included
>       in the initramfs
>     - gen_initramfs generate the gzipped cpio archive so we could simplify
>       the kbuild file (Makefile)
>     - utilising the kbuild infrastructure so when uid/gid root mapping changes
>       the initramfs will be rebuild
>     
>     With this change we have a much more robust initramfs generation.
> 
> 
> Should it stay this way or is it a bug?
Oh Crap. It's a bug. The intent it to rebuild initramfs when content of
the initramfs changes.
But not to rebuild content of initramfs of course.

No solution right now - will take a look during the weekend.

	Sam

Re: KBUILD tries to make initramfs contents :-)

[H. Peter Anvin]

Sam Ravnborg wrote:
>
> Should it stay this way or is it a bug?
> Oh Crap. It's a bug. The intent it to rebuild initramfs when content of
> the initramfs changes.
> But not to rebuild content of initramfs of course.
> 

No, it's worse than that.

The intent very much IS to rebuilt the content of initramfs, when it's 
included in the tree.

> No solution right now - will take a look during the weekend.

I guess the dependency-generation machinery will need to distinguish 
between in-tree and out-of-tree files.  It should be relatively easy, 
since out-of-tree files will have paths that begin with "/" or "../".

	-hpa