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From:   Masahiro Yamada <yamada.masahiro@socionext.com>
Date:   Wed, 8 May 2019 12:43:34 +0900
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Subject: Re: [PATCH v3] kheaders: Move from proc to sysfs
To:     "Joel Fernandes (Google)" <joel@joelfernandes.org>
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On Mon, May 6, 2019 at 10:37 AM Joel Fernandes (Google)
<joel@joelfernandes.org> wrote:
>
> The kheaders archive consisting of the kernel headers used for compiling
> bpf programs is in /proc. However there is concern that moving it here
> will make it permanent. Let us move it to /sys/kernel as discussed [1].
>
> [1] https://lore.kernel.org/patchwork/patch/1067310/#1265969
>
> Suggested-by: Steven Rostedt <rostedt@goodmis.org>
> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
> ---
> This patch applies on top of the previous patch that was applied to the
> driver tree:
> https://lore.kernel.org/patchwork/patch/1067310/
>
> v2->v3: Fixed sysfs file mode nit (Greg).
> v1->v2: Fixed some kconfig nits.
>
>  init/Kconfig                                | 16 ++++-----
>  kernel/Makefile                             |  4 +--
>  kernel/{gen_ikh_data.sh => gen_kheaders.sh} |  2 +-
>  kernel/kheaders.c                           | 40 +++++++++------------
>  4 files changed, 26 insertions(+), 36 deletions(-)
>  rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)
>
> diff --git a/init/Kconfig b/init/Kconfig
> index 26a364a95b57..c3661991b089 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -579,15 +579,13 @@ config IKCONFIG_PROC
>           This option enables access to the kernel configuration file
>           through /proc/config.gz.
>
> -config IKHEADERS_PROC
> -       tristate "Enable kernel header artifacts through /proc/kheaders.tar.xz"
> -       depends on PROC_FS
> -       help
> -         This option enables access to the kernel header and other artifacts that
> -         are generated during the build process. These can be used to build eBPF
> -         tracing programs, or similar programs.  If you build the headers as a
> -         module, a module called kheaders.ko is built which can be loaded on-demand
> -         to get access to the headers.
> +config IKHEADERS
> +       tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz"


I suggested "depends on SYSFS" twice, both in v1 and v2.

https://lore.kernel.org/patchwork/patch/1069806/#1266147
https://lore.kernel.org/patchwork/patch/1070005/#1266279


> +       help
> +         This option enables access to the in-kernel headers that are generated during
> +         the build process. These can be used to build eBPF tracing programs,
> +         or similar programs.  If you build the headers as a module, a module called
> +         kheaders.ko is built which can be loaded on-demand to get access to headers.
>
>  config LOG_BUF_SHIFT
>         int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"


-- 
Best Regards
Masahiro Yamada