On Fri, 2024-03-15 at 15:29 +0100, Benjamin Tissoires wrote:
This patch looks good to me, please see two nitpicks below.
Acked-by: Eduard Zingerman <eddyz87@xxxxxxxxx>
[...]
> @@ -1350,6 +1358,11 @@ BPF_CALL_3(bpf_timer_start, struct bpf_timer_kern *, timer, u64, nsecs, u64, fla
> goto out;
> }
>
> + if (t->is_sleepable && !(flags & BPF_F_TIMER_SLEEPABLE)) {
> + ret = -EINVAL;
> + goto out;
> + }
Nit:
the BPF_F_TIMER_ABS and BPF_F_TIMER_CPU_PIN don't affect
sleepable timers, should this check be changed to:
'(t->is_sleepable && flags != BPF_F_TIMER_SLEEPABLE)' ?
[...]
> @@ -12151,6 +12175,16 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
> }
> }
>
> + if (is_async_callback_calling_kfunc(meta.func_id)) {
> + err = push_callback_call(env, insn, insn_idx, meta.subprogno,
> + set_timer_callback_state);
Nit: still think that this fragment would be better as:
if (is_bpf_timer_set_sleepable_cb_impl_kfunc(meta.func_id)) {
err = push_callback_call(env, insn, insn_idx, meta.subprogno,
set_timer_callback_state);
Because of the 'set_timer_callback_state' passed to push_callback_call().
> + if (err) {
> + verbose(env, "kfunc %s#%d failed callback verification\n",
> + func_name, meta.func_id);
> + return err;
> + }
> + }
> +
> rcu_lock = is_kfunc_bpf_rcu_read_lock(&meta);
> rcu_unlock = is_kfunc_bpf_rcu_read_unlock(&meta);
>
