[Buildroot] [PATCH 3/4] core: introduce BR2_KERNEL_ARCH_OVERRIDE

[Romain Naour]

Hello Thomas, Arnout,

Le 12/01/2022 à 20:10, Arnout Vandecappelle a écrit :
> 
> 
> On 12/01/2022 12:04, Thomas De Schampheleire wrote:
>> Hi Romain,
>>
>> El lun, 10 ene 2022 a las 0:27, Romain Naour (<romain.naour at smile.fr>) escribió:
>>>
>>> Hello Thomas,
>>>
>>> Le 18/05/2021 à 13:36, Thomas De Schampheleire a écrit :
>>>> From: Thomas De Schampheleire <thomas.de_schampheleire at nokia.com>
>>>>
>>>> There are cases where a 64-bit architecture is running a 64-bit kernel but
>>>> 32-bit userspace. Examples include:
>>>>      * aarch64 architecture, with aarch64 kernel and 32-bit (ARM) userspace
>>>>      * x86_64 architecture, with x86_64 kernel and 32-bit (i386) userspace
>>>
>>> Can you provide a new qemu defconfig that cover this use case?
>>> This is for gitlab-ci runtime testing.
>>>
>>> Best regards,
>>> Romain
>>>
>>> PS: (This email doesn't count as a review of this series :))
>>
>>
>> Thanks for your interest in this series :-)
>>
>> Currently the qemu defconfig that I use uses an external toolchain
>> built via crosstool-ng. Crosstool-ng is capable of creating a multilib
>> toolchain supporting 32-bit and 64-bit binaries.
>> However, Buildroot does not currently support this for internal
>> toolchains. How do you suggest to proceed here?
>> Could we perhaps add a crosstool-ng-built multilib toolchain to the
>> Bootlin toolchains?
> 
>  Bootlin toolchains no - they are generated by Buildroot.

Indeed.

>  However, it would be useful to have such a toolchain as an autobuilder
> toolchain. We could use it both in a 32-bit and 64-bit config. We can simply add
> your binary to autobuild.buildroot.org/toolchains/tarballs and add two config
> fragments to support/config-fragments/autobuild.
> 
>  The same toolchain tarball can then also be used for a runtime test.

Agree, but we have to be able to rebuild them when needed.
A script or a simple text would be ok.

Best regards,
Romain

> 
>  Regards,
>  Arnout
>