Re: [PATCH] tools/perf: Fix to get the DW_AT_decl_file and DW_AT_call_file as unsinged data

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Mon, Nov 07, 2022 at 01:09:00PM -0800, Namhyung Kim escreveu:
> Hi Masami,
> 
> On Fri, Nov 4, 2022 at 8:01 PM Masami Hiramatsu (Google)
> <mhiramat@kernel.org> wrote:
> >
> > From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> >
> > Dwarf version 5 standard Sec 2.14 says that
> >
> >   Any debugging information entry representing the declaration of an object,
> >   module, subprogram or type may have DW_AT_decl_file, DW_AT_decl_line and
> >   DW_AT_decl_column attributes, each of whose value is an unsigned integer
> >   constant.
> >
> > So it should be an unsigned integer data. Also, even though the standard
> > doesn't clearly say the DW_AT_call_file is signed or unsigned, the
> > elfutils (eu-readelf) interprets it as unsigned integer data and it is
> > natural to handle it as unsigned integer data as same as DW_AT_decl_file.
> > This changes the DW_AT_call_file as unsigned integer data too.
> >
> > Fixes: 3f4460a28fb2 ("perf probe: Filter out redundant inline-instances")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks, applied.

- Arnaldo

 
> Thanks,
> Namhyung
> 
> 
> > ---
> >  tools/perf/util/dwarf-aux.c |   21 ++++-----------------
> >  1 file changed, 4 insertions(+), 17 deletions(-)
> >
> > diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
> > index 30b36b525681..b07414409771 100644
> > --- a/tools/perf/util/dwarf-aux.c
> > +++ b/tools/perf/util/dwarf-aux.c
> > @@ -315,19 +315,6 @@ static int die_get_attr_udata(Dwarf_Die *tp_die, unsigned int attr_name,
> >         return 0;
> >  }
> >
> > -/* Get attribute and translate it as a sdata */
> > -static int die_get_attr_sdata(Dwarf_Die *tp_die, unsigned int attr_name,
> > -                             Dwarf_Sword *result)
> > -{
> > -       Dwarf_Attribute attr;
> > -
> > -       if (dwarf_attr_integrate(tp_die, attr_name, &attr) == NULL ||
> > -           dwarf_formsdata(&attr, result) != 0)
> > -               return -ENOENT;
> > -
> > -       return 0;
> > -}
> > -
> >  /**
> >   * die_is_signed_type - Check whether a type DIE is signed or not
> >   * @tp_die: a DIE of a type
> > @@ -467,9 +454,9 @@ int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs)
> >  /* Get the call file index number in CU DIE */
> >  static int die_get_call_fileno(Dwarf_Die *in_die)
> >  {
> > -       Dwarf_Sword idx;
> > +       Dwarf_Word idx;
> >
> > -       if (die_get_attr_sdata(in_die, DW_AT_call_file, &idx) == 0)
> > +       if (die_get_attr_udata(in_die, DW_AT_call_file, &idx) == 0)
> >                 return (int)idx;
> >         else
> >                 return -ENOENT;
> > @@ -478,9 +465,9 @@ static int die_get_call_fileno(Dwarf_Die *in_die)
> >  /* Get the declared file index number in CU DIE */
> >  static int die_get_decl_fileno(Dwarf_Die *pdie)
> >  {
> > -       Dwarf_Sword idx;
> > +       Dwarf_Word idx;
> >
> > -       if (die_get_attr_sdata(pdie, DW_AT_decl_file, &idx) == 0)
> > +       if (die_get_attr_udata(pdie, DW_AT_decl_file, &idx) == 0)
> >                 return (int)idx;
> >         else
> >                 return -ENOENT;
> >

-- 

- Arnaldo