[poky] bitbake variable override (virtual/kernel)

[Prasant J]

On Mon, Dec 28, 2015 at 6:58 PM, Richard Purdie
<richard.purdie at linuxfoundation.org> wrote:
> On Mon, 2015-12-28 at 18:52 +0530, Prasant J wrote:
>> Hi,
>>
>> I'm putting together my custom layer with my machine configuration. I
>> have set PREFERRED_PROVIDER_virtual/kernel to build my kernel but it
>> is always overridden by distro configuration. Below is the output of
>> bitbake environment:
>>
>>
>> # $PREFERRED_PROVIDER_virtual/kernel [6 operations]
>> #   set /home/user/fsl-L3.14.52_1.1.0_ga/fsl-release-bsp/sources/meta
>> -fsl-arm/conf/machine/include/imx-base.inc:117
>> #     [_defaultval] "linux-imx"
>> #   finalize ast.py:325 [finalize]
>> #     "was: linux-imx"
>> #   override[mx6]:set /home/user/fsl-L3.14.52_1.1.0_ga/fsl-release
>> -bsp/build-fb/conf/local.conf:26
>> #     "linux-myboard-imx6"
>> #   override[mx6]:set /home/user/fsl-L3.14.52_1.1.0_ga/fsl-release
>> -bsp/sources/mylayer/meta-newlayer/conf/machine/mymachine.conf:17
>> #     "linux-myboard-imx6"
>> #   override[mx6]:set /home/user/fsl-L3.14.52_1.1.0_ga/fsl-release
>> -bsp/sources/meta-fsl-bsp-release/imx/meta
>> -sdk/conf/distro/include/fsl-imx-preferred-env.inc:7
>> #     "linux-imx"
>> #   finalize override[mx6]:
>> #     "linux-imx"
>> # pre-expansion value:
>> #   "linux-imx"
>> PREFERRED_PROVIDER_virtual/kernel="linux-imx"
>>
>> From the above it seems that distro configuration overrides my custom
>> machine + glocal conf/local.conf configuration.
>>
>>
>> Is it expected? So should I also create a custom DISTRO?
>> Is there a way to extend the DISTRO configuration and only override
>> virtual/kernel value?
>>
>>
>> Any input will be of help to me. Thanks!
>
> Distro overrides are more powerful so yes, this isn't surprising. You
> could disable the mx6 override (which is probably added to
> MACHINEOVERRIDES or DISTROOVERRIDES)?
>
> Something like:
>
> MACHINEOVERRIDES_remove = ":mx6"
>
> might even work.
>

Thanks for inputs!

I'm also building for imx6. Removing override may remove many other
settings that I do not want to change.

Is it possible to extend DISTRO configuration and change
PREFERRED_PROVIDER_virtual/kernel in the  extended configuration?

Regards, PJ