Bug 14064

Summary:	Modify kernel.bbclass to allow for easy in-kernel-tree defconfig use
Product:	[Build System, Metadata & Runtime] OE-Core	Reporter:	Eduardas Meile <eduardas>
Component:	kernel	Assignee:	Bruce Ashfield <bruce.ashfield>
Status:	RESOLVED DUPLICATE	QA Contact:
Severity:	enhancement
Priority:	Undecided	CC:	tom.zanussi
Version:	unspecified
Target Milestone:	---
Hardware:	All
OS:	Multiple
Whiteboard:
OS type for building Yocto:	---	Type of Regression:	---
Verified:		Documentation change:	Yes (doc changes required)

Description Eduardas Meile 2020-09-28 06:50:28 UTC

In practice I have found that it would be very convenient to just specify the in-tree defconfig name in the kernel bitbake recipe instead of copying it from kernel source into own layer metadata manually every time it needs to change. Something like this is implemented in Phytec's custom kconfig class here:

https://git.phytec.de/meta-phytec/tree/classes/kconfig.bbclass?h=dunfell

The variable is INTREE_DEFCONFIG

Also something similar is supposed to work with the kernel-yocto class and KBUILD_DEFCONFIG variable, though I have not been able to make it work properly for my mainline Linux 5.8.5 fork. Anyway, I don't think such a feature should
be exclusive to kernel-yocto or linux-yocto, but should be available using plain kernel.bbclass

Comment 1 Bruce Ashfield 2020-09-28 08:31:24 UTC

This isn't something we can or want to standardize in kernel.bbclass.

There are literally hundreds of users, and use cases for the core kernel.bbclass.

We can't keep them all happy, so we need to keep things minimal there.

Note: there is an outstanding feature to move the fragment support into a core location and make it optional, at that point, this will be addressed.

Closing this as "won't implmenent", since we already have something in bugzilla.

As for KBUILD_DEFCONFIG, it works here on all kernel versions, so you should open a specific bug with reproducing the issue you are seeing.

*** This bug has been marked as a duplicate of bug 8191 ***