Re: [PATCH] image: include image name in the kernel/initrd image copies

[Jan Kiszka <jan.kiszka@siemens.com>]

On 18.10.18 11:46, chombourger@gmail.com wrote:
> 
> Hi Jan,
> 
> See below
> 
> On Thursday, October 18, 2018 at 11:27:10 AM UTC+2, Jan Kiszka wrote:
> 
>     On 18.10.18 11:04, Cedric Hombourger wrote:
>      > The kernel and initrd images are really image-specific (especially the later
>      > with the initrd being created/updated as packages get installed into the
>     root
>      > file-system). Make sure we retain a per-image copy of these images in the
> 
>     I don't buy this argument yet: Which additional parameters besides the and the
>     MACHINE make kernel different?
> 
> 
> An image recipe may pull a different kernel than the default kernel proposed by 
> the MACHINE or DISTRO
> There are several ways: locally setting KERNEL_NAME, IMAGE_INSTALL_remove games, 
> etc.
> 
> This is obviously a less frequent use-case than the initrd which is evidently 
> populated based on hooks/scripts installed into your root file-system (and 
> therefore image dependent)

OK, in that light, it is something that should be called just like the generated 
image. But I think the whole beast needs rework now. See below.

> 
>     If there is any, can't we associate that
>     variation more directly with the image then? It's surely not the image
>     recipe name.
> 
> 
> Would you have a suggestion (based on the extra info I provided above)?
> 
> A possibly cleaner solution would be to NOT copy these files 
> into DEPLOY_DIR_IMAGE in the first place! and have e.g. wic plugins extract the 
> kernel/initrd images from the rootfs they are working with
> I am happy to rework this patch if breaking the API (by removing KERNEL_IMAGE 
> and INITRD_IMAGE) is an option

We have two use cases so far: QEMU and wic. Both work without downstream effort 
by just using those two variables. That by itself is not bad. An alternative 
might only by peeking directly into the rootfs trees of the images, i.e. 
avoiding the copying to deploy. Not sure, actually, what value this copy-out 
provides, at least as long as the user does not manual deployment of the artifacts.

Anyway. If we keep copy-out: Instead of appending further elements to the 
kernel/initrd prefix, we should really consolidate things. The image, maybe it 
be wic-generated or ext4-img or whatever, as well as associated artifacts should 
follow the same file naming scheme so that you can easily identify related 
artifacts.

Furthermore, we likely need to update things like 
do_copy_boot_files[stamp-extra-info], do_populate_sdk[stamp-extra-info] to 
follow those patterns as well.

Jan

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