Re: [PATCH bpf v2 2/2] samples/{bpf,hid}: fix broken vmlinux path for VMLINUX_BTF

[Nicolas Schier]

On Thu, Jan 23, 2025 at 02:19:50AM -0600, Jinghao Jia wrote:
> Commit 13b25489b6f8 ("kbuild: change working directory to external
> module directory with M=") changed kbuild working directory of bpf and
> hid samples to samples/{bpf,hid}, which broke the vmlinux path for
> VMLINUX_BTF, as the Makefiles assume the current work directory to be
> the kernel output directory and use a relative path (i.e., ./vmlinux):
> 
>   Makefile:316: *** Cannot find a vmlinux for VMLINUX_BTF at any of "  /path/to/linux/samples/bpf/vmlinux", build the kernel or set VMLINUX_BTF like "VMLINUX_BTF=/sys/kernel/btf/vmlinux" or VMLINUX_H variable.  Stop.
> 
> Correctly refer to the kernel output directory using $(objtree).
> 
> Fixes: 13b25489b6f8 ("kbuild: change working directory to external module directory with M=")
> Tested-by: Ruowen Qin <ruqin@xxxxxxxxxx>
> Signed-off-by: Jinghao Jia <jinghao7@xxxxxxxxxxxx>
> ---
>  samples/bpf/Makefile | 2 +-
>  samples/hid/Makefile | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Nicolas Schier <n.schier@xxxxxx>