Re: [PATCH bpf-next v4 15/18] bpf,x86: Implement JIT support for stack arguments

Alexei Starovoitov
2026-04-13T20:38:34Z

On Mon, Apr 13, 2026 at 1:32 PM Yonghong Song <yonghong.song@linux.dev> wrote:
>
>
>
> On 4/13/26 12:59 PM, Alexei Starovoitov wrote:
> > On Mon, Apr 13, 2026 at 10:26 AM Yonghong Song <yonghong.song@linux.dev> wrote:
> >>
> >> Yes, we can do something like below:
> >>
> >> case BPF_ST | BPF_MEM | BPF_DW:
> >> - if (adjust_stack_arg_off && insn->off == -outgoing_stack_arg_depth) {
> >> + if (dst_reg == BPF_REG_STACK_ARG_BASE && insn->off == -outgoing_stack_arg_depth) {
> > Something like that, but use BPF_REG_ARG_PTR name ?
> > here and in the verifier?
>
> We have a bunch of ARG_PTR_* (e.g. ARG_PTR_TO_MAP_VALUE, ...).
> So maybe BPF_REG_STACK_ARG_PTR to distinguish ARG_PTR_*?
> BPF_REG_STACK_ARG_BASE_PTR seems a better name as it does represents
> the base pointer for stack arguments of a particular function.
> But BPF_REG_STACK_ARG_BASE_PTR seems too long so BPF_REG_STACK_ARG_PTR?

both are too long.
I reacted to BPF_REG_STACK_ARG_BASE. Since it was already too long.
BPF_REG_PARAMS ?