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From:   Namhyung Kim <namhyung@gmail.com>
Date:   Mon, 5 Jul 2021 13:48:04 -0700
Message-ID: <CAM9d7cj2H75byaNH-n4XeKbMu30j6_P3TAPwpoE9R1LXVTTSwQ@mail.gmail.com>
Subject: Re: [PATCH 0/3] perf: Fix perf probe for Fedora34 glibc update
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        linux-perf-users <linux-perf-users@vger.kernel.org>,
        Sven Schnelle <svens@linux.ibm.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Stefan Liebler <stli@linux.ibm.com>,
        Thomas Richter <tmricht@linux.ibm.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Sat, Jul 3, 2021 at 8:36 AM Masami Hiramatsu <mhiramat@kernel.org> wrote:
>
> Hi Arnaldo,
>
> Here is a series of patches to fix the perf-probe error against the
> Fedora34 glibc update, which moves most of symbols from .symtab to
> .dynsym. The key is that the "most of" symbols moved, but it still
> have some PLT symbols in .symtab. Thus the perf symbol-elf failes to
> decode symbols.

Do you know what's the rationale of the move?
Is it a change from glibc or Fedora?

Thanks,
Namhyung


>
> Here is the original report from Thomas about this issue.
>
>  https://lore.kernel.org/linux-perf-users/f6752514-eaf9-371e-f81b-0d9e41ebae0c@linux.ibm.com/
>
> Thank you,
>
> ---
>
> Masami Hiramatsu (3):
>       perf-probe: Fix debuginfo__new() to enable build-id based debuginfo
>       perf symbol-elf: Decode dynsym even if symtab exists
>       perf probe: Do not show @plt function by default
>
>
>  tools/perf/builtin-probe.c     |    2 -
>  tools/perf/util/probe-finder.c |    5 ++
>  tools/perf/util/symbol-elf.c   |   82 ++++++++++++++++++++++++++--------------
>  3 files changed, 60 insertions(+), 29 deletions(-)
>
> --
> Masami Hiramatsu (Linaro) <mhiramat@kernel.org>