difficulties with KCONFIG_ALLCONFIG miniconfigs

difficulties with KCONFIG_ALLCONFIG miniconfigs

[Jeff Weber]

I am unable to pass required kernel config items via KCONFIG_ALLCONFIG
to kbuild.
I originally encountered issues with the
scripts/kconfig/merge_config.sh tool, but I've
isolated some of my issues to the examples below.  Kernel = 3.18.11 .
Help appreciated.

Case 1: Attempt to enable EXT4_FS using allnoconfig target.
Per ./fs/ext4/Kconfig, config EXT4_FS has no other dependencies.

$ cat ext4.cfg
CONFIG_EXT4_FS=y

$ KCONFIG_ALLCONFIG=ext4.cfg  make allnoconfig

$ grep CONFIG_EXT4_FS .config || echo not found
not found

Why was CONFIG_EXT4_FS not set?


Case 2: Attempt to disable SLUB_DEBUG using alldefconfig target.
Search of Kconfigs shows no other configs select SLUB_DEBUG .

$ cat no-slub-debug.cfg
CONFIG_SLUB_DEBUG=n

$ KCONFIG_ALLCONFIG=no-slub-debug.cfg make alldefconfig

$ grep SLUB_DEBUG .config
CONFIG_SLUB_DEBUG=y
# CONFIG_SLUB_DEBUG_ON is not set

Why was CONFIG_SLUB_DEBUG not disabled?

TIA,
Jeff

Re: difficulties with KCONFIG_ALLCONFIG miniconfigs

[Paul Bolle]

On Mon, 2015-04-13 at 15:17 -0500, Jeff Weber wrote:
> $ cat ext4.cfg
> CONFIG_EXT4_FS=y
> 
> $ KCONFIG_ALLCONFIG=ext4.cfg  make allnoconfig
> 
> $ grep CONFIG_EXT4_FS .config || echo not found
> not found
> 
> Why was CONFIG_EXT4_FS not set?

A search of EXT4_FS in make menuconfig inspired me to add
    CONFIG_BLOCK=y

to ext4.cfg.

> Case 2: Attempt to disable SLUB_DEBUG using alldefconfig target.
> Search of Kconfigs shows no other configs select SLUB_DEBUG .
> 
> $ cat no-slub-debug.cfg
> CONFIG_SLUB_DEBUG=n
> 
> $ KCONFIG_ALLCONFIG=no-slub-debug.cfg make alldefconfig
> 
> $ grep SLUB_DEBUG .config
> CONFIG_SLUB_DEBUG=y
> # CONFIG_SLUB_DEBUG_ON is not set
> 
> Why was CONFIG_SLUB_DEBUG not disabled?

Seeing that the Kconfig entry for SLUB_DEBUG reads
    config SLUB_DEBUG
        default y
        bool "Enable SLUB debugging support" if EXPERT
        depends on SLUB && SYSFS
        help
          [...]

I guessed that this no-slub-debug.cfg might work:
    CONFIG_EXPERT=y
    # CONFIG_SLUB_DEBUG is not set

Please don't ask me to explain why.


Paul Bolle