Add make target for generating current arch config

[afbjorklund]

make nativeconfig

• Compress the lima-guestagent in the installation directory #2426 (comment)

$ make config
cp config.mk .config
/usr/local/bin/kconfig-conf Kconfig
*
* Lima
*
guestagent OS: Linux (GUESTAGENT_OS_LINUX) [Y/n/?] 
guestagent Arch: x86_64 (GUESTAGENT_ARCH_X8664) [Y/n/?] 
guestagent Arch: aarch64 (GUESTAGENT_ARCH_AARCH64) [Y/n/?] 
guestagent Arch: armv7l (GUESTAGENT_ARCH_ARMV7L) [Y/n/?] 
guestagent Arch: riscv64 (GUESTAGENT_ARCH_RISCV64) [Y/n/?] 
#
# configuration written to .config
#

$ make menuconfig
cp config.mk .config
MENUCONFIG_STYLE=aquatic \
/usr/local/bin/kconfig-mconf Kconfig


*** End of the configuration.
*** Execute 'make' to start the build or try 'make help'.

The goal was to generate a config file, with only the current architecture.

---

Default config, empty defconfig:

#
# Automatically generated file; DO NOT EDIT.
# Lima
#
CONFIG_GUESTAGENT_OS_LINUX=y
CONFIG_GUESTAGENT_ARCH_X8664=y
CONFIG_GUESTAGENT_ARCH_AARCH64=y
CONFIG_GUESTAGENT_ARCH_ARMV7L=y
CONFIG_GUESTAGENT_ARCH_RISCV64=y

Could have used files:

arch/x86_64/defconfig
arch/aarch64/defconfig

As in the tool default:

ARCH=x86_64 kconfig-conf --defconfig Kconfig

***
*** Can't find default configuration "arch/x86_64/defconfig"!
***

arch/x86_64/config.mk

CONFIG_GUESTAGENT_OS_LINUX=y
CONFIG_GUESTAGENT_ARCH_X8664=y
CONFIG_GUESTAGENT_ARCH_AARCH64=n
CONFIG_GUESTAGENT_ARCH_ARMV7L=n
CONFIG_GUESTAGENT_ARCH_RISCV64=n

alternatively, defconfig:

# CONFIG_GUESTAGENT_ARCH_X8664 is not set
# CONFIG_GUESTAGENT_ARCH_ARMV7L is not set
# CONFIG_GUESTAGENT_ARCH_RISCV64 is not set

ARCH=aarch64 kconfig-conf --defconfig Kconfig

***
*** Can't find default configuration "arch/aarch64/defconfig"!
***

arch/aarch64/config.mk

CONFIG_GUESTAGENT_OS_LINUX=y
CONFIG_GUESTAGENT_ARCH_X8664=n
CONFIG_GUESTAGENT_ARCH_AARCH64=y
CONFIG_GUESTAGENT_ARCH_ARMV7L=n
CONFIG_GUESTAGENT_ARCH_RISCV64=n

alternatively, defconfig:

# CONFIG_GUESTAGENT_ARCH_AARCH64 is not set
# CONFIG_GUESTAGENT_ARCH_ARMV7L is not set
# CONFIG_GUESTAGENT_ARCH_RISCV64 is not set

The framework is overkill here, compared with kernel.

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch

[norio-nomura]

I agree with the opinion that a way to install only the native guest agent is needed, but I don’t quite understand why that would require kconfig support. It seems like this could be achieved without using kconfig.

[norio-nomura]

I don’t necessarily want to block this PR, but since I don't understand the reasons for its implementation, I don’t have the criteria to judge its merits and therefore cannot evaluate the PR.

[afbjorklund]

I agree with the opinion that a way to install only the native guest agent is needed, but I don’t quite understand why that would require kconfig support. It seems like this could be achieved without using kconfig.

The Kconfig is the configuration for the Makefile code, so enabling/disabling features is done there.
The output (.config) is not complicated: https://github.com/lima-vm/lima/blob/master/config.mk

A similar system is autoconf for automake, you might have seen a ./configure script being used?
That system is still (rather) simple for the end user, but is much more complicated for the developer.

[norio-nomura]

I understand what this PR is doing, but I still don’t understand why it’s necessary.

[afbjorklund]

I understand what this PR is doing, but I still don’t understand why it’s necessary.

The only requirement was to be able to build Lima for the host architecture only...

Building "minimal" does this, but it doesn't include any templates or helpers.

Current workaround is doing the quiz:

*
* Lima
*
guestagent OS: Linux (GUESTAGENT_OS_LINUX) [Y/n/?] (NEW) 
guestagent Arch: x86_64 (GUESTAGENT_ARCH_X8664) [Y/n/?] (NEW) y
guestagent Arch: aarch64 (GUESTAGENT_ARCH_AARCH64) [Y/n/?] (NEW) n
guestagent Arch: armv7l (GUESTAGENT_ARCH_ARMV7L) [Y/n/?] (NEW) n
guestagent Arch: riscv64 (GUESTAGENT_ARCH_RISCV64) [Y/n/?] (NEW) n
guestagent compress (GUESTAGENT_COMPRESS) [N/y/?] (NEW) 
#
# configuration written to .config
#

i.e. same as what the new script does

[norio-nomura]

The only requirement was to be able to build Lima for the host architecture only...

I’ve drafted a PR #2638 that refactors the Makefile, including a solution to that requirement.

[afbjorklund]

In other news, I updated kconfig-frontends so that it builds without warnings (on Linux or Mac).

You do have to brew install qt@5 if you want the Qt GUI, it did not yet support Qt6 in Linux 5.4.

[afbjorklund]

An improvement would be to rename it from "defconfig" to "nativeconfig" or somesuch.

And to copy the non-arch fields from the config.mk, instead of duplicating them here.