Re: [PATCH 0/3] tracing: Fix some selftest issues

[Steven Rostedt <rostedt@goodmis.org>]

On Fri, 31 May 2024 11:37:21 +0900
Masami Hiramatsu (Google) <mhiramat@kernel.org> wrote:

> So, in summary, it is designed to be a module. Steve, I think these tests
> should be kept as modules. There are many reason to do so.
> 
>  - This test is designed to be used as module.
>  - This can conflict with other boot time selftest if it is embedded.
>  - We can make these tests and boot time selftest mutable exclusive but
>    if we make these tests as modules, we can build and run both tests
>    safely.
>  - Embedding these tests leave new events when the kernel boot, which
>    user must be cleaned up by manual.
> 
> What would you think?

I was mostly following what Ingo told me long ago, where having it
built in is just one more way to test it ;-)

But that said, from your first patch, you show the stack dump and
mention:

> Since the kprobes and synth event generation tests adds and enable
> generated events in init_module() and delete it in exit_module(),
> if we make it as built-in, those events are left in kernel and cause
> kprobe event self-test failure.

But you don't explain what exactly the conflict is. What about those
events causes kprobe selftests to fail?


-- Steve