Re: [PATCH v3 0/7] Isar cross-compilation support

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

Hi Alex,

On 2018-07-22 22:32, Alexander Smirnov wrote:
> Hi Jan,
> 
> On 07/22/2018 11:15 PM, Alexander Smirnov wrote:
>>
>>
>> On 07/20/2018 08:56 AM, Jan Kiszka wrote:
>>> Hi Alex,
>>>
>>> On 2018-07-19 22:59, Alexander Smirnov wrote:
>>>> Hi Jan,
>>>>
>>>> [...]
>>>>
>>>>>> Just an observation, you use here buster but I didn't test it.
>>>>>
>>>>> Yes, but only for the pre-built u-boot package, and only for the 
>>>>> Orange
>>>>> Pi. See conf/multiconfig/preferences.orangepi-zero.conf.
>>>>
>>>> I've found several issue with v3 regarding kernel and modules 
>>>> cross-compilation. I've fixed them and pushed asmirnov/devel branch.
>>>>
>>>> Now I'm able to cross-build orangepi kernel and example-module for 
>>>> it, huh! :-)
>>>
>>> That's good news, and I can confirm that at least the linux-headers 
>>> packages looks good now. It's also clear now that there can be no 
>>> mixed-mode when building kernel modules because this package with its 
>>> host tools is generated for the build host, not the target arch.
>>>
>>> However, I'm still stuck on the Python dependency problems. I bet you 
>>> can also reproduce them by declaring the hello package to 
>>> build-depend on "python". Same for "python-pip".
>>>
> 
> I've found an interesting notes here:
> 
> https://wiki.debian.org/DebianBootstrap/TODO#Remove_blockers_for_:any_and_:native_introduction 
> 
> 
> adding native qualifier for python solves the issue for me (i.e. 
> python:native).

Yes, already wanted to report (but got distracted by Jailhouse bugs)
that I found the same hint in

https://groups.google.com/forum/#!topic/linux.debian.devel.mentors/OuuorAmGgWc

Adding :native to python solved the build issue for non-root-initramfs
in jailhouse-image. But I have harder nuts in that repo. :)

The jailhouse package has build dependencies on python-mako, a package
mentioned above as cross-incompatible, and also python-pip. Those can be
installed by adding :native as well, but dpgk-buildpackage will then
fail on validating the build dependencies. That can be skipped, though:

diff --git a/meta/recipes-devtools/buildchroot/files/build.sh b/meta/recipes-devtools/buildchroot/files/build.sh
index 40ba410..aba2042 100644
--- a/meta/recipes-devtools/buildchroot/files/build.sh
+++ b/meta/recipes-devtools/buildchroot/files/build.sh
@@ -61,4 +61,4 @@ for i in configure aclocal.m4 Makefile.am Makefile.in; do
 done
 
 # Build the package
-dpkg-buildpackage -a$target_arch
+dpkg-buildpackage -a$target_arch --no-check-builddeps

With that change and by adding arm64 support, I was now able to build
*all* jailhouse-image targets cross!

> 
> Do you think current status contains enough functionality for the first
> implementation, so I could format clean patches and add the documentation?

Yes, definitely, with that workaround and arm64 support, please. Maybe
you have an idea how to limit the --no-check-builddeps to cross-builds.

I noticed one further minor thing: wic images seem to enforce generating
buildchroot-target. I suppose wic will be fine with buildchroot-host as
well. Would be nice to avoid that redundant bootstrap if possible.

Thanks,
Jan

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Corporate Competence Center Embedded Linux