Re: [RFC PATCH bpf-next v1 0/3] bpf: Add BPF program type for overriding tracepoint probes

[Fuyu Zhao]

On 9/18/2025 11:32 PM, Steven Rostedt wrote:
> On Thu, 18 Sep 2025 21:15:57 +0800
> Fuyu Zhao <zhaofuyu@xxxxxxxx> wrote:
> 
>> As for the reason not to unregister and register a new callback:
>> callbacks registered directly inside the kernel cannot be unregistered from
>> user space. From user space, we can only attach additional callbacks
>> with BPF programs, but can not remove or replace the ones already
>> registered in the kernel. Therefore, an override mechanism is needed.
> 
> The fact that user space cannot unregister or override the current
> callbacks, to me is a feature and not a bug.
> 
> -- Steve

I see, thank you for sharing your view — I’ll keep it in mind.

Sincerely,
Fuyu