On Sun, Aug 27, 2023 at 08:27:44AM -0700, Yonghong Song wrote:
> case KF_ARG_PTR_TO_ALLOC_BTF_ID:
> - if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) {
> + if (reg->type == (PTR_TO_BTF_ID | MEM_ALLOC)) {
> + if (meta->func_id != special_kfunc_list[KF_bpf_obj_drop_impl]) {
> + verbose(env, "arg#%d expected for bpf_obj_drop_impl()\n", i);
> + return -EINVAL;
> + }
> + } else if (reg->type == (PTR_TO_BTF_ID | MEM_ALLOC | MEM_PERCPU)) {
> + if (meta->func_id != special_kfunc_list[KF_bpf_percpu_obj_drop_impl]) {
> + verbose(env, "arg#%d expected for bpf_percpu_obj_drop_impl()\n", i);
> + return -EINVAL;
> + }
> + } else {
> verbose(env, "arg#%d expected pointer to allocated object\n", i);
> return -EINVAL;
This is a bit too much of hard coded checks for "suppose to be generic" __alloc arg suffix in kfuncs.
We only have two such kfuncs:
bpf_percpu_obj_drop_impl(void *p__alloc
bpf_obj_drop_impl(void *p__alloc
so above works and I don't have a good suggestion how it can be improved,
but would be great to follow up to clean this up somehow.
