Re: [PATCH RFC bpf-next 3/7] bpf: fix the usage of BPF_TRAMP_F_SKIP_FRAME

Alexei Starovoitov
2025-11-14T18:23:34Z

On Fri, Nov 14, 2025 at 1:25 AM Menglong Dong <menglong8.dong@gmail.com> wrote:
>
> Some places calculate the origin_call by checking if
> BPF_TRAMP_F_SKIP_FRAME is set. However, it should use
> BPF_TRAMP_F_ORIG_STACK for this propose. Just fix them.
>
> Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
> ---
> arch/riscv/net/bpf_jit_comp64.c | 2 +-
> arch/x86/net/bpf_jit_comp.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
> index 45cbc7c6fe49..21c70ae3296b 100644
> --- a/arch/riscv/net/bpf_jit_comp64.c
> +++ b/arch/riscv/net/bpf_jit_comp64.c
> @@ -1131,7 +1131,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
> store_args(nr_arg_slots, args_off, ctx);
>
> /* skip to actual body of traced function */
> - if (flags & BPF_TRAMP_F_SKIP_FRAME)
> + if (flags & BPF_TRAMP_F_ORIG_STACK)
> orig_call += RV_FENTRY_NINSNS * 4;
>
> if (flags & BPF_TRAMP_F_CALL_ORIG) {
> diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
> index de5083cb1d37..2d300ab37cdd 100644
> --- a/arch/x86/net/bpf_jit_comp.c
> +++ b/arch/x86/net/bpf_jit_comp.c
> @@ -3272,7 +3272,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
>
> arg_stack_off = stack_size;
>
> - if (flags & BPF_TRAMP_F_SKIP_FRAME) {
> + if (flags & BPF_TRAMP_F_CALL_ORIG) {

Good catch. Ack. Pls carry it in respin, so I don't
forget that I looked at it.