Way to combine kernel and initrd on x86 platform?

Way to combine kernel and initrd on x86 platform?

[Subodh Nijsure]

I have been using the arch/powerpc/boot/wrapper scripts to combine
linux and initrd.gz to create a single image for distribution.

Is there similar wrapper possible for x86 platforms also? This is my
first week of working on x86 embedded platform.

I know of initramfs option in 2.6 kernel, however the contents of
initrd in my case are created after the kernel is build i.e. will have
to "patch in" the initramfs at later point in build process.

/Subodh

Re: Way to combine kernel and initrd on x86 platform?

[H. Peter Anvin]

On 07/22/2009 02:15 PM, Subodh Nijsure wrote:
> I have been using the arch/powerpc/boot/wrapper scripts to combine
> linux and initrd.gz to create a single image for distribution.
> 
> Is there similar wrapper possible for x86 platforms also? This is my
> first week of working on x86 embedded platform.
> 
> I know of initramfs option in 2.6 kernel, however the contents of
> initrd in my case are created after the kernel is build i.e. will have
> to "patch in" the initramfs at later point in build process.

If your bootloader can support ELF, Multiboot, or NBI, you can use
Wraplinux:

	http://www.kernel.org/pub/linux/utils/boot/wraplinux/

bzImage support would be possible, but it isn't in this version (noone
has asked for it).

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

Re: Way to combine kernel and initrd on x86 platform?

[Subodh Nijsure]

On Wed, Jul 22, 2009 at 7:40 PM, H. Peter Anvin<hpa@zytor.com> wrote:
> On 07/22/2009 02:15 PM, Subodh Nijsure wrote:

>
> If your bootloader can support ELF, Multiboot, or NBI, you can use
> Wraplinux:
>
>        http://www.kernel.org/pub/linux/utils/boot/wraplinux/
>
> bzImage support would be possible, but it isn't in this version (noone
> has asked for it).
>

Sorry if I am not being very smart  here, confused by the remark "
bzImage support would not be possible"

I was able create wrapped image using command

wraplinux -p "console=ttyS0,115200" -i initrd.gz -o
vmlinux.initrd.wrap arch/i386/boot/bzImage

I am using wraplinux version 1.6

if I use any other image  wraplinux doesn't find the version
information and initrd image doesn't get attached.

What file should I be specifying as the 'kernel' when I execute
wrapimage  if not the bzImage?

( I am working with 2.6.23 kernel)

On my board I can boot the standard bzImage, but not able to load the
wrapped image produced by wraplinux command. Would very much
appreciate hints...

Regards,
/Subodh



>        -hpa
>
> --
> H. Peter Anvin, Intel Open Source Technology Center
> I work for Intel.  I don't speak on their behalf.
>
>

Re: Way to combine kernel and initrd on x86 platform?

[H. Peter Anvin]

Subodh Nijsure wrote:
> 
> Sorry if I am not being very smart  here, confused by the remark "
> bzImage support would not be possible"
> 
> I was able create wrapped image using command
> 
> wraplinux -p "console=ttyS0,115200" -i initrd.gz -o
> vmlinux.initrd.wrap arch/i386/boot/bzImage
> 
> I am using wraplinux version 1.6
> 
> if I use any other image  wraplinux doesn't find the version
> information and initrd image doesn't get attached.
> 
> What file should I be specifying as the 'kernel' when I execute
> wrapimage  if not the bzImage?
> 
> ( I am working with 2.6.23 kernel)
> 
> On my board I can boot the standard bzImage, but not able to load the
> wrapped image produced by wraplinux command. Would very much
> appreciate hints...
> 

What I mean is that Wraplinux accepts bzImage as input and outputs ELF,
NBI or Multiboot.  Depending on the bootloader on your board, you may
need to select one or the other of these formats, or might not be able
to at all.  It does not *output* bzImage, and it isn't 100% trivial to
make it do so.

	-hpa