Re: [RFC][PATCH 0/6] Isar build reproducibility

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

Hi Alex,

On 2018-01-02 15:57, Alexander Smirnov wrote:
> Hello all,
> 
> this series proposes the way how build reproducibility could be implemented
> in Isar. General idea is to get the list of all the necessary packages for
> build, fetch them and create local repo, that will be used for further
> builds/
> 
> Briefly speeking, it works like the following:
> 
> 1. User sets the list of images that should be 'reproducible' in
>    BASE_APT_IMAGES variable in local.conf file.

What speaks against making every image reproducible? I strongly assume
this is the common case. There should be a way to disable that, and that
could be local.conf controlled.

Is there a technical reason the core needs to know the name of the
reproducible image? Or can be control this on a per-build basis,
including all images of that build?

And will all images of the same bitbake run (thinking of multiconfig...)
share also the same base-apt repo, or is that per image?

> 
> 2. Based on the list of images above, Isar will derive all the run-time and
>    build dependencies for these images.
> 
> 3. Using multistrap, Isar will fetch the list of packages and create base-apt
>    local repository.
> 
> 4. Now buildchroot and image root filesystems are generated using base-apt.
> 
> Some notes:
> 
> 1. base-apt repository is mounted to buildchroot, so Isar packages are
>    able to install necessary deps via apt-get.

This does not your provide the packages a way to feed their own build
results into the same repo, does it? I'm referring to the issue that
Christian described
(https://groups.google.com/forum/#!msg/isar-users/efer3RF989o/r-zfUNNDAgAJ)
and which I ran into as well meanwhile.
> 
> 2. bitbake events are used to clean up buildchroot. I haven't found another
>    way how base-apt could be unmounted. So it's mounted once before any
>    package starts building and unmounted by bitbake event:
>    bb.event.BuildCompleted.

What is the implication of that? At least to me (without detailed
understanding of bitbake), this remains unclear.

> 
> This series works good with latest next. Any comments are welcome.
> 
> Happy New Year 2018! :-)

Same to you.

Jan

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