Re: [PATCH v3] kheaders: Move from proc to sysfs

From: Masahiro Yamada
Date: Tue May 07 2019 - 23:45:29 EST


On Mon, May 6, 2019 at 10:37 AM Joel Fernandes (Google)
<joel@xxxxxxxxxxxxxxxxx> 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@xxxxxxxxxxx>
> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> ---
> 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