Re: perf/ftrace lockup on 3.12-rc6 with trigger code

From: Ingo Molnar
Date: Fri Oct 25 2013 - 06:19:51 EST

* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> > Urgh, I had turned those on to try to debug something and forgot
> > to disable. I feel like I saw this problem before I had those
> > enabled so I guess I have to start from scratch fuzzing to see
> > if I can get a more generally reproducible trace.

Btw., even if various config options are enabled, we don't want the
kernel to lock up. So it might not be _the_ bug you are looking, but
it certainly looks like _a_ bug.

> Looks like something is incorrectly enabling function tracer
> within perf. Peter told me that there's some ref count bug that
> may use data after being freed on exit.
> I tried the program that you attached in you previous email, and
> was not able to hit the bug. Are you able to hit the bug with that
> code each time?

A full .config and a SHA1 of the tested tree would definitely be


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