On Mon, 5 Jul 2021 13:48:04 -0700
Namhyung Kim [off-list ref] wrote:

On Sat, Jul 3, 2021 at 8:36 AM Masami Hiramatsu [off-list ref] wrote:

quoted

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?

I don't know, but it seems that this happens when updating glibc package,
the version is same but revision is different. Also, in the Ubuntu, I saw
all symbols has been moved to .dynsym in older glibc.
Thus I guess that this depends on the build option or configuration.
Might Fedora change the packaging script?

Thank you,

Thanks,
Namhyung

quoted

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/ (local)

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) [off-list ref]

-- 
Masami Hiramatsu [off-list ref]