Re: [PATCH v2 bpf] kbuild: fix dependencies for DEBUG_INFO_BTF

From: KP Singh
Date: Tue Mar 31 2020 - 18:40:28 EST


On 01-Apr 00:55, Slava Bacherikov wrote:
> Currently turning on DEBUG_INFO_SPLIT when DEBUG_INFO_BTF is also
> enabled will produce invalid btf file, since gen_btf function in
> link-vmlinux.sh script doesn't handle *.dwo files.
>
> Enabling DEBUG_INFO_REDUCED will also produce invalid btf file, and
> using GCC_PLUGIN_RANDSTRUCT with BTF makes no sense.
>
> Signed-off-by: Slava Bacherikov <slava@xxxxxxxxxxxx>
> Reported-by: Jann Horn <jannh@xxxxxxxxxx>
> Reported-by: Liu Yiding <liuyd.fnst@xxxxxxxxxxxxxx>
> Fixes: e83b9f55448a ("kbuild: add ability to generate BTF type info for vmlinux")

I can say that I also got invalid BTF when I tried using
DEBUG_INFO_REDUCED.

So here's a first one from of these from me :)

Acked-by: KP Singh <kpsingh@xxxxxxxxxx>

> ---
> lib/Kconfig.debug | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index f61d834e02fe..9ae288e2a6c0 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -223,6 +223,7 @@ config DEBUG_INFO_DWARF4
> config DEBUG_INFO_BTF
> bool "Generate BTF typeinfo"
> depends on DEBUG_INFO
> + depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED && !GCC_PLUGIN_RANDSTRUCT
> help
> Generate deduplicated BTF type information from DWARF debug info.
> Turning this on expects presence of pahole tool, which will convert
> --
> 2.24.1
>