Re: [PATCH 0/4] perf: Make SIGTRAP and __perf_pending_irq() work on RT.

From: Marco Elver
Date: Mon Mar 11 2024 - 12:32:35 EST


On Mon, 11 Mar 2024 at 16:59, Sebastian Andrzej Siewior
<bigeasy@xxxxxxxxxxxxx> wrote:
>
> On 2024-03-11 11:34:18 [+0100], Marco Elver wrote:
> > Unfortunately there's a bug in it somewhere. It can be reproduced with
> > tools/testing/selftests/perf_events/remove_on_exec.
> >
> > (FWIW, the kselftests in that directory are more aggressive test cases
> > that I never figured out how to properly port to the 'perf test'
> > framework: sigtrap_threads is a more aggressive version of the 'sigtrap'
> > perf test, and remove_on_exec has no perf test counterpart.)
>
> You posted to warnings, I can only reproduce the second one. Based on the
> backtrace it is obvious what happens and I dare to say that I know why…
> Let me try address them.

I guess I got lucky with hitting 2 warnings instantly. It might be
necessary to run remove_on_exec several times, or even start several
instances of it concurrently (something like "for x in {0..100}; do
(./remove_on_exec &); done" might do the trick).