Re: [PATCH 04/23] kconfig: set SYMBOL_AUTO to the symbol marked with defconfig_list
From: Masahiro Yamada
Date: Thu Mar 01 2018 - 10:06:07 EST
2018-02-17 3:38 GMT+09:00 Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>:
> The 'defconfig_list' is a weird attribute. If the '.config' is
> missing, conf_read_simple() iterates over all visible defaults,
> then it uses the first one for which fopen() succeeds.
>
> config DEFCONFIG_LIST
> string
> depends on !UML
> option defconfig_list
> default "/lib/modules/$UNAME_RELEASE/.config"
> default "/etc/kernel-config"
> default "/boot/config-$UNAME_RELEASE"
> default "$ARCH_DEFCONFIG"
> default "arch/$ARCH/defconfig"
>
> However, like other symbols, the first visible default is always
> written out to the .config file. This might be different from what
> has been actually used.
>
> For example, on my machine, the third one "/boot/config-$UNAME_RELEASE"
> is opened, like follows:
>
> $ rm .config
> $ make oldconfig 2>/dev/null
> scripts/kconfig/conf --oldconfig Kconfig
> #
> # using defaults found in /boot/config-4.4.0-112-generic
> #
> *
> * Restart config...
> *
> *
> * IRQ subsystem
> *
> Expose irq internals in debugfs (GENERIC_IRQ_DEBUGFS) [N/y/?] (NEW)
>
> However, the resulted .config file contains the first one since it is
> visible:
>
> $ grep CONFIG_DEFCONFIG_LIST .config
> CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
>
> In order to stop confusing people, prevent this CONFIG option from
> being written to the .config file.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> ---
This one is almost trivial, so I will pick it up now.
Ulf, do you have any comment about this one?
> I'd like to fix the root case of this weirdness later.
> (and other 'option' attributes as well)
>
> But, this series is focusing a more important work in a bigger picture.
>
> For now, I decided to just hide CONFIG_DEFCONFIG_LIST
> from the .config file.
>
>
> scripts/kconfig/menu.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
> index 9922285..36cd3e1 100644
> --- a/scripts/kconfig/menu.c
> +++ b/scripts/kconfig/menu.c
> @@ -212,6 +212,7 @@ void menu_add_option(int token, char *arg)
> sym_defconfig_list = current_entry->sym;
> else if (sym_defconfig_list != current_entry->sym)
> zconf_error("trying to redefine defconfig symbol");
> + sym_defconfig_list->flags |= SYMBOL_AUTO;
> break;
> case T_OPT_ENV:
> prop_add_env(arg);
> --
> 2.7.4
>
> --
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--
Best Regards
Masahiro Yamada