[OE-core] [PATCH v3] elfutils: add PACKAGECONFIG for compression algorithms

[Ross Burton]

On 29/10/2019 21:46, Dan Callaghan wrote:
> I couldn't find anything that would ever use the bzip2 decompression in
> elfutils, so I had a quick look at why they even added bzip2 support in
> the first place. It turns out it was for reading compressed kernel
> images (presumably, in the elfutils tools like eu-readelf):
> 
> https://sourceware.org/git/?p=elfutils.git;a=commitdiff;h=d6ccdc1a05f27bf0bb5d802ec14f879aa9fe3e98
> 
>      commit d6ccdc1a05f27bf0bb5d802ec14f879aa9fe3e98
>      Author: Roland McGrath <roland at redhat.com>
>      Date:   Wed Aug 26 00:23:01 2009 -0700
> 
>          libdwfl: Support Linux bzip2 kernel images for automatic decompression.
> 
> And indeed on my Fedora host eu-readelf can decode ELF information from
> a kernel bzImage, but the eu-readelf built by Yocto's elfutils-native
> recipe says "not a valid ELF file" when I feed it the same bzImage.
> 
> Whether that's useful or not is a different question. In our product
> I am planning to disable bzip2 (because we don't use the elfutils tools
> for anything) and enable xz (for .gnu_debugdata sections).

Good digging, thanks.

Lets default to bzip being off for now, and then if anyone does want 
this then they can just turn it on.

Ross