Re: [PATCH bpf-next v5 07/17] bpf: XDP metadata RX kfuncs

Martin KaFai Lau
2022-12-23T00:31:38Z

On 12/20/22 2:20 PM, Stanislav Fomichev wrote:
> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
> index bafcb7a3ae6f..6d81b14361e3 100644
> --- a/kernel/bpf/core.c
> +++ b/kernel/bpf/core.c
> @@ -2097,6 +2097,14 @@ bool bpf_prog_map_compatible(struct bpf_map *map,
> if (fp->kprobe_override)
> return false;
>
> + /* XDP programs inserted into maps are not guaranteed to run on
> + * a particular netdev (and can run outside driver context entirely
> + * in the case of devmap and cpumap). Until device checks
> + * are implemented, prohibit adding dev-bound programs to program maps.
> + */
> + if (bpf_prog_is_dev_bound(fp->aux))
> + return false;
> +

There is a recent change in the same function in the bpf tree, commit
1c123c567fb1. fyi.

[ ... ]

> diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> index fdfdcab4a59d..320451a0be3e 100644
> --- a/kernel/bpf/verifier.c
> +++ b/kernel/bpf/verifier.c
> @@ -2081,6 +2081,22 @@ static struct btf *find_kfunc_desc_btf(struct bpf_verifier_env *env, s16 offset)
> return btf_vmlinux ?: ERR_PTR(-ENOENT);
> }
>
> +int bpf_dev_bound_kfunc_check(struct bpf_verifier_env *env,
> + struct bpf_prog_aux *prog_aux)

nit. Move the dev bound related function to offload.c. &env->log can be passed
instead of env and then use bpf_log().

Others lgtm.