Re: [PATCH bpf-next v3] bpftool: Add support for custom BTF path in prog load/loadall

[Quentin Monnet <qmo@kernel.org>]

2025-05-16 11:23 UTC+0800 ~ Jiayuan Chen <jiayuan.chen@linux.dev>
> This patch exposes the btf_custom_path feature to bpftool, allowing users
> to specify a custom BTF file when loading BPF programs using prog load or
> prog loadall commands.
> 
> The argument 'btf_custom_path' in libbpf is used for those kernels that
> don't have CONFIG_DEBUG_INFO_BTF enabled but still want to perform CO-RE
> relocations.
> 
> Suggested-by: Quentin Monnet <qmo@kernel.org>
> Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
> 
> ---
> V2 -> V3: Optimized document grammar and some prompts
> https://lore.kernel.org/bpf/20250515065018.240188-1-jiayuan.chen@linux.dev/
> V1 -> V2: Added bash completion and documentation
> https://lore.kernel.org/bpf/20250513035853.75820-1-jiayuan.chen@linux.dev/
> ---
>  tools/bpf/bpftool/Documentation/bpftool-prog.rst |  8 +++++++-
>  tools/bpf/bpftool/bash-completion/bpftool        |  4 ++--
>  tools/bpf/bpftool/prog.c                         | 12 +++++++++++-
>  3 files changed, 20 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
> index d6304e01afe0..4dce43e8e8a3 100644
> --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
> +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
> @@ -127,7 +127,7 @@ bpftool prog pin *PROG* *FILE*
>      Note: *FILE* must be located in *bpffs* mount. It must not contain a dot
>      character ('.'), which is reserved for future extensions of *bpffs*.
>  
> -bpftool prog { load | loadall } *OBJ* *PATH* [type *TYPE*] [map { idx *IDX* | name *NAME* } *MAP*] [{ offload_dev | xdpmeta_dev } *NAME*] [pinmaps *MAP_DIR*] [autoattach]
> +bpftool prog { load | loadall } *OBJ* *PATH* [type *TYPE*] [map { idx *IDX* | name *NAME* } *MAP*] [{ offload_dev | xdpmeta_dev } *NAME*] [pinmaps *MAP_DIR*] [autoattach] [kernel_btf *BTF_FILE*]

Woops, I just realised we also need to add kernel_btf to the command
summary at the top of the document (line 34), sorry for missing it
during the previous pass. Please add it, and mark v4 as:

    Reviewed-by: Quentin Monnet <qmo@kernel.org>

Thanks!