Re: [PATCH] kbuild: disable DEBUG_INFO_SPLIT when BTF is on

From: Andrii Nakryiko
Date: Tue Mar 31 2020 - 15:45:59 EST


On Tue, Mar 31, 2020 at 9:57 AM Slava Bacherikov <slava@xxxxxxxxxxxx> 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.
>
> Signed-off-by: Slava Bacherikov <slava@xxxxxxxxxxxx>
> ---
> lib/Kconfig.debug | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index f61d834e02fe..a9429ef5eec8 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

Thanks for following up! This looks good, but I think there are more
DWARF-related configs that should be banned. See [0] and [1]. If you
don't mind, let's use your patch to disable all of them in one go. So
can you please update and disable DEBUG_INFO_REDUCED and
GCC_PLUGIN_RANDSTRUCT? Thanks!

[0] https://lore.kernel.org/bpf/202003311110.2B08091E@keescook
[1] https://lore.kernel.org/bpf/a2b1a025-6a70-c3a5-fc19-155f0266946a@xxxxxx


> help
> Generate deduplicated BTF type information from DWARF debug info.
> Turning this on expects presence of pahole tool, which will convert
> --
> 2.24.1
>