Re: [RFC PATCH v1 02/14] bpf: Process global subprog's exception propagation

[Eduard Zingerman <eddyz87@gmail.com>]

On Fri, 2024-02-16 at 22:50 +0100, Kumar Kartikeya Dwivedi wrote:
[...]

> > Also, did you consider global subprograms that always throw?
> > E.g. do some logging and unconditionally call bpf_throw().
> > 
> 
> I have an example for that in the exception test suite, but I will add
> a test for that with lingering references around.

I meant that for some global subprograms it is not necessary to
explore both throwing and non-throwing branches, e.g.:

  void my_throw(void) {
    bpf_printk("oh no, oh no, oh no-no-no-...");
    bpf_throw(0);
  }

  SEC("tp")
  int foo(...) {
    ...
    if (a > 10)
      my_throw();
    ... here 'a' is always <= 10 ...
  }

[...]

> > Nit: Maybe move this log entry to do_check?
> >      It would be printed right before returning to do_check() anyways.
> >      Maybe add a log level check?
> > 
> 
> Hmm, true. I was actually even considering whether all frame_desc logs
> should also be LOG_LEVEL2?

Right, makes sense.