Messages in this thread | | | Date | Fri, 10 Jul 2020 21:14:22 +0900 | From | Masami Hiramatsu <> | Subject | Re: [PATCH 4/4] perf-probe: Warn if the target function is GNU Indirect function |
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On Fri, 10 Jul 2020 16:45:12 +0530 Srikar Dronamraju <srikar@linux.vnet.ibm.com> wrote:
> * Masami Hiramatsu <mhiramat@kernel.org> [2020-07-09 17:07:31]: > > > Reported-by: Andi Kleen <andi@firstfloor.org> > > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > > --- > > tools/perf/util/probe-event.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > > index 1e95a336862c..671176d39569 100644 > > --- a/tools/perf/util/probe-event.c > > +++ b/tools/perf/util/probe-event.c > > @@ -379,6 +379,11 @@ static int find_alternative_probe_point(struct debuginfo *dinfo, > > address = sym->start; > > else > > address = map->unmap_ip(map, sym->start) - map->reloc; > > + if (sym->type == STT_GNU_IFUNC) { > > + pr_warning("Warning: The probe address (0x%lx) is in a GNU indirect function.\n" > > + "This may not work as you expected unless you intend to probe the indirect function.\n", > > + (unsigned long)address); > > + } > > Are these GNU indirect functions possible in kernel? If not we could move > this warning under if (uprobes)
OK, I'll move it under if (uprobes).
> > Also instead of printing the address, can we print the pp->function?
Hmm, OK. But it may not help user because the pp->function will the name specified by user...
Thank you,
-- Masami Hiramatsu <mhiramat@kernel.org>
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