[2/2] binutils: add support for dumping BTF info

  This patch adds a new command line option --btf[=SECTION] to objdump to
dump a textual representation of the BTF data stored in section SECTION.
If no section name is given, then the default of .BTF is used.

The textual representation is the same as used by the Linux kernel
bpftool utility.

Signed-off-by: David Faust <david.faust@oss.qualcomm.com>
---
 binutils/doc/binutils.texi |   7 +
 binutils/objdump.c         | 265 +++++++++++++++++++++++++++++++++++++
 2 files changed, 272 insertions(+)
  

Hi Faust.

This patch also LGTM.

Same remark than about the other email:

Assuming that BTF falls within the BPF realm (which I think it is a fair
assumption, but please wait for a day or so in case some global
maintainer has some objection) this patch is OK.

Thanks!


> This patch adds a new command line option --btf[=SECTION] to objdump to
> dump a textual representation of the BTF data stored in section SECTION.
> If no section name is given, then the default of .BTF is used.
>
> The textual representation is the same as used by the Linux kernel
> bpftool utility.
>
> Signed-off-by: David Faust <david.faust@oss.qualcomm.com>
> ---
>  binutils/doc/binutils.texi |   7 +
>  binutils/objdump.c         | 265 +++++++++++++++++++++++++++++++++++++
>  2 files changed, 272 insertions(+)
>
> diff --git a/binutils/doc/binutils.texi b/binutils/doc/binutils.texi
> index 198ae8244ef..afb284d6ad0 100644
> --- a/binutils/doc/binutils.texi
> +++ b/binutils/doc/binutils.texi
> @@ -2353,6 +2353,7 @@ objdump [@option{-a}|@option{--archive-headers}]
>          [@option{--debug-dir=@file{dir}}]
>          [@option{--map-global-vars}]
>          [@option{-L}|@option{--process-links}]
> +        [@option{--btf=}@var{section}]
>          [@option{--ctf=}@var{section}]
>          [@option{--sframe=}@var{section}]
>          [@option{-G}|@option{--stabs}]
> @@ -3017,6 +3018,12 @@ Enable additional checks for consistency of Dwarf information.
>  @item --debug-dir=@file{dir}
>  Search @file{dir} when looking for separate debug info files.
>  
> +@item --btf[=@var{section}]
> +@cindex BTF
> +@cindex BPF Type Format
> +Display the contents of the specified BTF section.
> +By default, display the contents of the section named @var{.BTF}.
> +
>  @include ctf.options.texi
>  
>  @include sframe.options.texi
> diff --git a/binutils/objdump.c b/binutils/objdump.c
> index 944b81b17e0..ad6da31b577 100644
> --- a/binutils/objdump.c
> +++ b/binutils/objdump.c
> @@ -57,6 +57,7 @@
>  #include "demanguse.h"
>  #include "dwarf.h"
>  #include "ctf-api.h"
> +#include "btf.h"
>  #include "sframe-api.h"
>  #include "getopt.h"
>  #include "safe-ctype.h"
> @@ -109,6 +110,8 @@ static int dump_ctf_section_info;       /* --ctf */
>  static char *dump_ctf_section_name;
>  static char *dump_ctf_parent_name;	/* --ctf-parent */
>  static char *dump_ctf_parent_section_name;	/* --ctf-parent-section */
> +static int dump_btf_section_info;	/* --btf */
> +static char *dump_btf_section_name;
>  static int dump_sframe_section_info;	/* --sframe */
>  static char *dump_sframe_section_name;
>  static int do_demangle;			/* -C, --demangle */
> @@ -338,6 +341,8 @@ usage (FILE *stream, int status)
>    fprintf (stream, _("\
>        --ctf[=SECTION]      Display CTF info from SECTION, (default `.ctf')\n"));
>  #endif
> +  fprintf (stream, _("\
> +      --btf[=SECTION]      Display BTF info from SECTION, (default '.BTF')\n"));
>    fprintf (stream, _("\
>        --sframe[=SECTION]   Display SFrame info from SECTION, (default '.sframe')\n"));
>    fprintf (stream, _("\
> @@ -494,6 +499,7 @@ enum option_values
>      OPTION_NO_RECURSE_LIMIT,
>      OPTION_INLINES,
>      OPTION_SOURCE_COMMENT,
> +    OPTION_BTF,
>  #ifdef ENABLE_LIBCTF
>      OPTION_CTF,
>      OPTION_CTF_PARENT,
> @@ -511,6 +517,7 @@ static struct option long_options[]=
>    {"all-headers", no_argument, NULL, 'x'},
>    {"architecture", required_argument, NULL, 'm'},
>    {"archive-headers", no_argument, NULL, 'a'},
> +  {"btf", optional_argument, NULL, OPTION_BTF},
>  #ifdef ENABLE_LIBCTF
>    {"ctf", optional_argument, NULL, OPTION_CTF},
>    {"ctf-parent", required_argument, NULL, OPTION_CTF_PARENT},
> @@ -4832,6 +4839,256 @@ dump_bfd_header (bfd *abfd)
>  }
>  
>  
> +static void
> +dump_btf_record (bfd *abfd, bfd_byte *buf,
> +		 bfd_vma str_off, bfd_vma type_off,
> +		 uint32_t type_id, struct btf_type *t)
> +{
> +  uint32_t kind = BTF_INFO_KIND (t->info);
> +  uint32_t kflag = BTF_INFO_KFLAG (t->info);
> +  uint32_t vlen = BTF_INFO_VLEN (t->info);
> +
> +  const char *name
> +    = t->name_off == 0 ? "(anon)" : (const char *) buf + str_off + t->name_off;
> +
> +  bfd_byte *payload = buf + type_off + sizeof (struct btf_type);
> +
> +  printf ("[%u] ", type_id);
> +  switch (kind)
> +    {
> +    case BTF_KIND_INT:
> +      {
> +	uint32_t int_data = btf_read_integral (abfd, payload);
> +	printf ("INT '%s' size=%u bits_offset=%u nr_bits=%u",
> +		name,
> +		BTF_INT_BITS (int_data) / 8,
> +		BTF_INT_OFFSET (int_data),
> +		BTF_INT_BITS (int_data));
> +
> +	uint32_t encoding = BTF_INT_ENCODING (int_data);
> +	if (encoding != 0)
> +	  {
> +	    printf (" encoding=");
> +	    char *sep = "";
> +	    if (encoding & 0x1)
> +	      {
> +		printf ("SIGNED");
> +		sep = ",";
> +	      }
> +	    if (encoding & 0x2)
> +	      {
> +		printf ("%sCHAR", sep);
> +		sep = ",";
> +	      }
> +	    if (encoding & 0x4)
> +	      {
> +		printf ("%sBOOL", sep);
> +		sep = ",";
> +	      }
> +	  }
> +	break;
> +      }
> +    case BTF_KIND_FLOAT:
> +      printf ("FLOAT '%s' size=%u", name, t->size);
> +      break;
> +    case BTF_KIND_ARRAY:
> +      {
> +	struct btf_array *array = btf_read_array (abfd, payload);
> +	printf ("ARRAY '%s' type_id=%u index_type_id=%u nr_elems=%u",
> +		name, array->type, array->index_type, array->nelems);
> +	free (array);
> +	break;
> +      }
> +    case BTF_KIND_PTR:
> +      /* Fallthrough.  */
> +    case BTF_KIND_TYPEDEF:
> +      /* Fallthrough.  */
> +    case BTF_KIND_CONST:
> +      /* Fallthrough.  */
> +    case BTF_KIND_VOLATILE:
> +      /* Fallthrough.  */
> +    case BTF_KIND_RESTRICT:
> +      /* Fallthrough.  */
> +    case BTF_KIND_TYPE_TAG:
> +      printf ("%s '%s' type_id=%u",
> +	      (kind == BTF_KIND_PTR ? "PTR"
> +	       : kind == BTF_KIND_TYPEDEF ? "TYPEDEF"
> +	       : kind == BTF_KIND_CONST ? "CONST"
> +	       : kind == BTF_KIND_VOLATILE ? "VOLATILE"
> +	       : kind == BTF_KIND_RESTRICT ? "RESTRICT" : "UNKNOWN"),
> +	      name, t->type);
> +      break;
> +    case BTF_KIND_DECL_TAG:
> +      {
> +	struct btf_decl_tag *decltag = btf_read_decl_tag (abfd, payload);
> +	printf ("DECL_TAG '%s' type_id=%u, component_idx=%u",
> +		name, t->type, decltag->component_idx);
> +	free (decltag);
> +	break;
> +      }
> +    case BTF_KIND_FWD:
> +      printf ("FWD '%s' fwd_kind=%s",
> +	      name, kflag ? "union" : "struct");
> +      break;
> +    case BTF_KIND_FUNC:
> +      /* Note: linkage is encoded directly in the vlen field.  */
> +      printf ("FUNC '%s' type_id=%u linkage=%s",
> +	      name, t->type,
> +	      vlen == BTF_FUNC_STATIC ? "static"
> +	      : vlen == BTF_FUNC_GLOBAL ? "global"
> +	      : vlen == BTF_FUNC_EXTERN ? "extern"
> +	      : "unknown");
> +      break;
> +    case BTF_KIND_VAR:
> +      {
> +	struct btf_var *var = btf_read_var (abfd, payload);
> +	printf ("VAR '%s' type_id=%u linkage=%s",
> +		name, t->type,
> +		var->linkage == BTF_VAR_STATIC ? "static"
> +		: var->linkage == BTF_VAR_GLOBAL_ALLOCATED ? "global-alloc"
> +		: var->linkage == BTF_VAR_GLOBAL_EXTERN ? "global-extern"
> +		: "unknown");
> +	free (var);
> +	break;
> +      }
> +    case BTF_KIND_STRUCT:
> +      /* Fallthrough.  */
> +    case BTF_KIND_UNION:
> +      {
> +	printf ("%s '%s' size=%u vlen=%u",
> +		kind == BTF_KIND_STRUCT ? "STRUCT" : "UNION",
> +		name, t->size, vlen);
> +
> +	for (uint32_t i = 0; i < vlen; i++)
> +	  {
> +	    struct btf_member *member = btf_read_member (abfd, payload);
> +	    printf ("\n        '%s' type_id=%u ",
> +		    member->name_off == 0 ? "(anon)"
> +		     : (char *) buf + str_off + member->name_off,
> +		    member->type);
> +	    if (kflag)
> +	      {
> +		/* The member may be a bit-field.  */
> +		uint32_t bit_size = BTF_MEMBER_BITFIELD_SIZE (member->offset);
> +		uint32_t bit_offs = BTF_MEMBER_BITFIELD_OFFSET (member->offset);
> +		printf ("bits_offset=%u", bit_offs);
> +		if (bit_size > 0)
> +		  printf (" bitfield_size=%u", bit_size);
> +	      }
> +	    else
> +	      printf ("bits_offset=%u", member->offset);
> +
> +	    payload += sizeof (struct btf_member);
> +	    free (member);
> +	  }
> +	break;
> +      }
> +    case BTF_KIND_ENUM:
> +      /* Fallthrough.  */
> +    case BTF_KIND_ENUM64:
> +      {
> +	printf ("%s '%s' encoding=%s size=%u vlen=%u",
> +		kind == BTF_KIND_ENUM ? "ENUM" : "ENUM64",
> +		name, kflag ? "SIGNED" : "UNSIGNED",
> +		t->size, vlen);
> +	for (uint32_t i = 0; i < vlen; i++)
> +	  {
> +	    if (kind == BTF_KIND_ENUM)
> +	      {
> +		struct btf_enum *en = btf_read_enum (abfd, payload);
> +		char *en_name = (char *) buf + str_off + en->name_off;
> +		if (kflag)
> +		  printf ("\n        '%s' val=%d", en_name, en->val);
> +		else
> +		  printf ("\n        '%s' val=%u", en_name, (uint32_t) en->val);
> +		payload += sizeof (struct btf_enum);
> +		free (en);
> +	      }
> +	    else
> +	      {
> +		struct btf_enum64 *en = btf_read_enum64 (abfd, payload);
> +		char *en_name = (char *) buf + str_off + en->name_off;
> +		int64_t value = BTF_ENUM64_VALUE (en);
> +		if (kflag)
> +		  printf ("\n        '%s' val=%ld", en_name, value);
> +		else
> +		  printf ("\n        '%s' val=%lu", en_name,
> +			  (uint64_t) value);
> +		payload += sizeof (struct btf_enum64);
> +		free (en);
> +	      }
> +	  }
> +	break;
> +      }
> +    case BTF_KIND_FUNC_PROTO:
> +      {
> +	printf ("FUNC_PROTO '%s' ret_type_id=%u vlen=%u",
> +	       name, t->type, vlen);
> +	for (uint32_t i = 0; i < vlen; i++)
> +	  {
> +	    struct btf_param *param = btf_read_param (abfd, payload);
> +	    printf ("\n        '%s' type_id=%u",
> +		    param->name_off == 0 ? "(anon)"
> +		     : (char *) buf + str_off + param->name_off,
> +		    param->type);
> +	    payload += sizeof (struct btf_param);
> +	    free (param);
> +	  }
> +      }
> +      break;
> +    case BTF_KIND_DATASEC:
> +      {
> +	printf ("DATASEC '%s' size=%u vlen=%u",
> +		name, t->size, vlen);
> +	for (uint32_t i = 0; i < vlen; i++)
> +	  {
> +	    struct btf_var_secinfo *var = btf_read_var_secinfo (abfd, payload);
> +	    printf ("\n        type_id=%u offset=%u size=%u",
> +		    var->type, var->offset, var->size);
> +	    payload += sizeof (struct btf_var_secinfo);
> +	    free (var);
> +	  }
> +	break;
> +      }
> +    default:
> +      printf ("UNKNOWN entry kind %u", BTF_INFO_KIND (t->info));
> +      break;
> +    }
> +  printf ("\n");
> +}
> +
> +/* Dump all of the BTF info in section SEC_NAME.  */
> +
> +static void
> +dump_btf (bfd *abfd, const char *sec_name)
> +{
> +  asection *sec;
> +  if (sec_name == NULL)
> +    sec_name = ".BTF";
> +
> +  sec = bfd_get_section_by_name (abfd, sec_name);
> +  if (sec == NULL)
> +    {
> +      printf (_("No %s section present\n"), sanitize_string (sec_name));
> +      my_bfd_nonfatal (bfd_get_filename (abfd));
> +      return;
> +    }
> +
> +  if (!(bfd_section_flags (sec) & SEC_HAS_CONTENTS))
> +    {
> +      bfd_set_error (bfd_error_no_contents);
> +      return;
> +    }
> +
> +  if (!btf_map (abfd, sec, dump_btf_record))
> +    {
> +      printf (_("Invalid BTF data in section %s\n"),
> +	      sanitize_string (sec_name));
> +      my_bfd_nonfatal (bfd_get_filename (abfd));
> +    }
> +}
> +
> +
>  #ifdef ENABLE_LIBCTF
>  /* Formatting callback function passed to ctf_dump.  Returns either the pointer
>     it is passed, or a pointer to newly-allocated storage, in which case
> @@ -5893,6 +6150,8 @@ dump_bfd (bfd *abfd, bool is_mainfile)
>      dump_dwarf (abfd, is_mainfile);
>    if (is_mainfile || process_links)
>      {
> +      if (dump_btf_section_info)
> +	dump_btf (abfd, dump_btf_section_name);
>        if (dump_ctf_section_info)
>  	dump_ctf (abfd, dump_ctf_section_name, dump_ctf_parent_name,
>  		  dump_ctf_parent_section_name);
> @@ -6408,6 +6667,12 @@ main (int argc, char **argv)
>  	  dump_ctf_parent_section_name = xstrdup (optarg);
>  	  break;
>  #endif
> +	case OPTION_BTF:
> +	  dump_btf_section_info = true;
> +	  if (optarg)
> +	    dump_btf_section_name = xstrdup (optarg);
> +	  seenflag = true;
> +	  break;
>  	case OPTION_SFRAME:
>  	  dump_sframe_section_info = true;
  

On 9/30/26 11:36 AM, Jose E. Marchesi wrote:
> 
> Hi Faust.
> 
> This patch also LGTM.
> 
> Same remark than about the other email:
> 
> Assuming that BTF falls within the BPF realm (which I think it is a fair
> assumption, but please wait for a day or so in case some global
> maintainer has some objection) this patch is OK.
> 
> Thanks!
> 

I've just pushed both patches.
Thanks.

> 
>> This patch adds a new command line option --btf[=SECTION] to objdump to
>> dump a textual representation of the BTF data stored in section SECTION.
>> If no section name is given, then the default of .BTF is used.
>>
>> The textual representation is the same as used by the Linux kernel
>> bpftool utility.
>>
>> Signed-off-by: David Faust <david.faust@oss.qualcomm.com>
>> ---
>>  binutils/doc/binutils.texi |   7 +
>>  binutils/objdump.c         | 265 +++++++++++++++++++++++++++++++++++++
>>  2 files changed, 272 insertions(+)
>>
>> diff --git a/binutils/doc/binutils.texi b/binutils/doc/binutils.texi
>> index 198ae8244ef..afb284d6ad0 100644
>> --- a/binutils/doc/binutils.texi
>> +++ b/binutils/doc/binutils.texi
>> @@ -2353,6 +2353,7 @@ objdump [@option{-a}|@option{--archive-headers}]
>>          [@option{--debug-dir=@file{dir}}]
>>          [@option{--map-global-vars}]
>>          [@option{-L}|@option{--process-links}]
>> +        [@option{--btf=}@var{section}]
>>          [@option{--ctf=}@var{section}]
>>          [@option{--sframe=}@var{section}]
>>          [@option{-G}|@option{--stabs}]
>> @@ -3017,6 +3018,12 @@ Enable additional checks for consistency of Dwarf information.
>>  @item --debug-dir=@file{dir}
>>  Search @file{dir} when looking for separate debug info files.
>>  
>> +@item --btf[=@var{section}]
>> +@cindex BTF
>> +@cindex BPF Type Format
>> +Display the contents of the specified BTF section.
>> +By default, display the contents of the section named @var{.BTF}.
>> +
>>  @include ctf.options.texi
>>  
>>  @include sframe.options.texi
>> diff --git a/binutils/objdump.c b/binutils/objdump.c
>> index 944b81b17e0..ad6da31b577 100644
>> --- a/binutils/objdump.c
>> +++ b/binutils/objdump.c
>> @@ -57,6 +57,7 @@
>>  #include "demanguse.h"
>>  #include "dwarf.h"
>>  #include "ctf-api.h"
>> +#include "btf.h"
>>  #include "sframe-api.h"
>>  #include "getopt.h"
>>  #include "safe-ctype.h"
>> @@ -109,6 +110,8 @@ static int dump_ctf_section_info;       /* --ctf */
>>  static char *dump_ctf_section_name;
>>  static char *dump_ctf_parent_name;	/* --ctf-parent */
>>  static char *dump_ctf_parent_section_name;	/* --ctf-parent-section */
>> +static int dump_btf_section_info;	/* --btf */
>> +static char *dump_btf_section_name;
>>  static int dump_sframe_section_info;	/* --sframe */
>>  static char *dump_sframe_section_name;
>>  static int do_demangle;			/* -C, --demangle */
>> @@ -338,6 +341,8 @@ usage (FILE *stream, int status)
>>    fprintf (stream, _("\
>>        --ctf[=SECTION]      Display CTF info from SECTION, (default `.ctf')\n"));
>>  #endif
>> +  fprintf (stream, _("\
>> +      --btf[=SECTION]      Display BTF info from SECTION, (default '.BTF')\n"));
>>    fprintf (stream, _("\
>>        --sframe[=SECTION]   Display SFrame info from SECTION, (default '.sframe')\n"));
>>    fprintf (stream, _("\
>> @@ -494,6 +499,7 @@ enum option_values
>>      OPTION_NO_RECURSE_LIMIT,
>>      OPTION_INLINES,
>>      OPTION_SOURCE_COMMENT,
>> +    OPTION_BTF,
>>  #ifdef ENABLE_LIBCTF
>>      OPTION_CTF,
>>      OPTION_CTF_PARENT,
>> @@ -511,6 +517,7 @@ static struct option long_options[]=
>>    {"all-headers", no_argument, NULL, 'x'},
>>    {"architecture", required_argument, NULL, 'm'},
>>    {"archive-headers", no_argument, NULL, 'a'},
>> +  {"btf", optional_argument, NULL, OPTION_BTF},
>>  #ifdef ENABLE_LIBCTF
>>    {"ctf", optional_argument, NULL, OPTION_CTF},
>>    {"ctf-parent", required_argument, NULL, OPTION_CTF_PARENT},
>> @@ -4832,6 +4839,256 @@ dump_bfd_header (bfd *abfd)
>>  }
>>  
>>  
>> +static void
>> +dump_btf_record (bfd *abfd, bfd_byte *buf,
>> +		 bfd_vma str_off, bfd_vma type_off,
>> +		 uint32_t type_id, struct btf_type *t)
>> +{
>> +  uint32_t kind = BTF_INFO_KIND (t->info);
>> +  uint32_t kflag = BTF_INFO_KFLAG (t->info);
>> +  uint32_t vlen = BTF_INFO_VLEN (t->info);
>> +
>> +  const char *name
>> +    = t->name_off == 0 ? "(anon)" : (const char *) buf + str_off + t->name_off;
>> +
>> +  bfd_byte *payload = buf + type_off + sizeof (struct btf_type);
>> +
>> +  printf ("[%u] ", type_id);
>> +  switch (kind)
>> +    {
>> +    case BTF_KIND_INT:
>> +      {
>> +	uint32_t int_data = btf_read_integral (abfd, payload);
>> +	printf ("INT '%s' size=%u bits_offset=%u nr_bits=%u",
>> +		name,
>> +		BTF_INT_BITS (int_data) / 8,
>> +		BTF_INT_OFFSET (int_data),
>> +		BTF_INT_BITS (int_data));
>> +
>> +	uint32_t encoding = BTF_INT_ENCODING (int_data);
>> +	if (encoding != 0)
>> +	  {
>> +	    printf (" encoding=");
>> +	    char *sep = "";
>> +	    if (encoding & 0x1)
>> +	      {
>> +		printf ("SIGNED");
>> +		sep = ",";
>> +	      }
>> +	    if (encoding & 0x2)
>> +	      {
>> +		printf ("%sCHAR", sep);
>> +		sep = ",";
>> +	      }
>> +	    if (encoding & 0x4)
>> +	      {
>> +		printf ("%sBOOL", sep);
>> +		sep = ",";
>> +	      }
>> +	  }
>> +	break;
>> +      }
>> +    case BTF_KIND_FLOAT:
>> +      printf ("FLOAT '%s' size=%u", name, t->size);
>> +      break;
>> +    case BTF_KIND_ARRAY:
>> +      {
>> +	struct btf_array *array = btf_read_array (abfd, payload);
>> +	printf ("ARRAY '%s' type_id=%u index_type_id=%u nr_elems=%u",
>> +		name, array->type, array->index_type, array->nelems);
>> +	free (array);
>> +	break;
>> +      }
>> +    case BTF_KIND_PTR:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_TYPEDEF:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_CONST:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_VOLATILE:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_RESTRICT:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_TYPE_TAG:
>> +      printf ("%s '%s' type_id=%u",
>> +	      (kind == BTF_KIND_PTR ? "PTR"
>> +	       : kind == BTF_KIND_TYPEDEF ? "TYPEDEF"
>> +	       : kind == BTF_KIND_CONST ? "CONST"
>> +	       : kind == BTF_KIND_VOLATILE ? "VOLATILE"
>> +	       : kind == BTF_KIND_RESTRICT ? "RESTRICT" : "UNKNOWN"),
>> +	      name, t->type);
>> +      break;
>> +    case BTF_KIND_DECL_TAG:
>> +      {
>> +	struct btf_decl_tag *decltag = btf_read_decl_tag (abfd, payload);
>> +	printf ("DECL_TAG '%s' type_id=%u, component_idx=%u",
>> +		name, t->type, decltag->component_idx);
>> +	free (decltag);
>> +	break;
>> +      }
>> +    case BTF_KIND_FWD:
>> +      printf ("FWD '%s' fwd_kind=%s",
>> +	      name, kflag ? "union" : "struct");
>> +      break;
>> +    case BTF_KIND_FUNC:
>> +      /* Note: linkage is encoded directly in the vlen field.  */
>> +      printf ("FUNC '%s' type_id=%u linkage=%s",
>> +	      name, t->type,
>> +	      vlen == BTF_FUNC_STATIC ? "static"
>> +	      : vlen == BTF_FUNC_GLOBAL ? "global"
>> +	      : vlen == BTF_FUNC_EXTERN ? "extern"
>> +	      : "unknown");
>> +      break;
>> +    case BTF_KIND_VAR:
>> +      {
>> +	struct btf_var *var = btf_read_var (abfd, payload);
>> +	printf ("VAR '%s' type_id=%u linkage=%s",
>> +		name, t->type,
>> +		var->linkage == BTF_VAR_STATIC ? "static"
>> +		: var->linkage == BTF_VAR_GLOBAL_ALLOCATED ? "global-alloc"
>> +		: var->linkage == BTF_VAR_GLOBAL_EXTERN ? "global-extern"
>> +		: "unknown");
>> +	free (var);
>> +	break;
>> +      }
>> +    case BTF_KIND_STRUCT:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_UNION:
>> +      {
>> +	printf ("%s '%s' size=%u vlen=%u",
>> +		kind == BTF_KIND_STRUCT ? "STRUCT" : "UNION",
>> +		name, t->size, vlen);
>> +
>> +	for (uint32_t i = 0; i < vlen; i++)
>> +	  {
>> +	    struct btf_member *member = btf_read_member (abfd, payload);
>> +	    printf ("\n        '%s' type_id=%u ",
>> +		    member->name_off == 0 ? "(anon)"
>> +		     : (char *) buf + str_off + member->name_off,
>> +		    member->type);
>> +	    if (kflag)
>> +	      {
>> +		/* The member may be a bit-field.  */
>> +		uint32_t bit_size = BTF_MEMBER_BITFIELD_SIZE (member->offset);
>> +		uint32_t bit_offs = BTF_MEMBER_BITFIELD_OFFSET (member->offset);
>> +		printf ("bits_offset=%u", bit_offs);
>> +		if (bit_size > 0)
>> +		  printf (" bitfield_size=%u", bit_size);
>> +	      }
>> +	    else
>> +	      printf ("bits_offset=%u", member->offset);
>> +
>> +	    payload += sizeof (struct btf_member);
>> +	    free (member);
>> +	  }
>> +	break;
>> +      }
>> +    case BTF_KIND_ENUM:
>> +      /* Fallthrough.  */
>> +    case BTF_KIND_ENUM64:
>> +      {
>> +	printf ("%s '%s' encoding=%s size=%u vlen=%u",
>> +		kind == BTF_KIND_ENUM ? "ENUM" : "ENUM64",
>> +		name, kflag ? "SIGNED" : "UNSIGNED",
>> +		t->size, vlen);
>> +	for (uint32_t i = 0; i < vlen; i++)
>> +	  {
>> +	    if (kind == BTF_KIND_ENUM)
>> +	      {
>> +		struct btf_enum *en = btf_read_enum (abfd, payload);
>> +		char *en_name = (char *) buf + str_off + en->name_off;
>> +		if (kflag)
>> +		  printf ("\n        '%s' val=%d", en_name, en->val);
>> +		else
>> +		  printf ("\n        '%s' val=%u", en_name, (uint32_t) en->val);
>> +		payload += sizeof (struct btf_enum);
>> +		free (en);
>> +	      }
>> +	    else
>> +	      {
>> +		struct btf_enum64 *en = btf_read_enum64 (abfd, payload);
>> +		char *en_name = (char *) buf + str_off + en->name_off;
>> +		int64_t value = BTF_ENUM64_VALUE (en);
>> +		if (kflag)
>> +		  printf ("\n        '%s' val=%ld", en_name, value);
>> +		else
>> +		  printf ("\n        '%s' val=%lu", en_name,
>> +			  (uint64_t) value);
>> +		payload += sizeof (struct btf_enum64);
>> +		free (en);
>> +	      }
>> +	  }
>> +	break;
>> +      }
>> +    case BTF_KIND_FUNC_PROTO:
>> +      {
>> +	printf ("FUNC_PROTO '%s' ret_type_id=%u vlen=%u",
>> +	       name, t->type, vlen);
>> +	for (uint32_t i = 0; i < vlen; i++)
>> +	  {
>> +	    struct btf_param *param = btf_read_param (abfd, payload);
>> +	    printf ("\n        '%s' type_id=%u",
>> +		    param->name_off == 0 ? "(anon)"
>> +		     : (char *) buf + str_off + param->name_off,
>> +		    param->type);
>> +	    payload += sizeof (struct btf_param);
>> +	    free (param);
>> +	  }
>> +      }
>> +      break;
>> +    case BTF_KIND_DATASEC:
>> +      {
>> +	printf ("DATASEC '%s' size=%u vlen=%u",
>> +		name, t->size, vlen);
>> +	for (uint32_t i = 0; i < vlen; i++)
>> +	  {
>> +	    struct btf_var_secinfo *var = btf_read_var_secinfo (abfd, payload);
>> +	    printf ("\n        type_id=%u offset=%u size=%u",
>> +		    var->type, var->offset, var->size);
>> +	    payload += sizeof (struct btf_var_secinfo);
>> +	    free (var);
>> +	  }
>> +	break;
>> +      }
>> +    default:
>> +      printf ("UNKNOWN entry kind %u", BTF_INFO_KIND (t->info));
>> +      break;
>> +    }
>> +  printf ("\n");
>> +}
>> +
>> +/* Dump all of the BTF info in section SEC_NAME.  */
>> +
>> +static void
>> +dump_btf (bfd *abfd, const char *sec_name)
>> +{
>> +  asection *sec;
>> +  if (sec_name == NULL)
>> +    sec_name = ".BTF";
>> +
>> +  sec = bfd_get_section_by_name (abfd, sec_name);
>> +  if (sec == NULL)
>> +    {
>> +      printf (_("No %s section present\n"), sanitize_string (sec_name));
>> +      my_bfd_nonfatal (bfd_get_filename (abfd));
>> +      return;
>> +    }
>> +
>> +  if (!(bfd_section_flags (sec) & SEC_HAS_CONTENTS))
>> +    {
>> +      bfd_set_error (bfd_error_no_contents);
>> +      return;
>> +    }
>> +
>> +  if (!btf_map (abfd, sec, dump_btf_record))
>> +    {
>> +      printf (_("Invalid BTF data in section %s\n"),
>> +	      sanitize_string (sec_name));
>> +      my_bfd_nonfatal (bfd_get_filename (abfd));
>> +    }
>> +}
>> +
>> +
>>  #ifdef ENABLE_LIBCTF
>>  /* Formatting callback function passed to ctf_dump.  Returns either the pointer
>>     it is passed, or a pointer to newly-allocated storage, in which case
>> @@ -5893,6 +6150,8 @@ dump_bfd (bfd *abfd, bool is_mainfile)
>>      dump_dwarf (abfd, is_mainfile);
>>    if (is_mainfile || process_links)
>>      {
>> +      if (dump_btf_section_info)
>> +	dump_btf (abfd, dump_btf_section_name);
>>        if (dump_ctf_section_info)
>>  	dump_ctf (abfd, dump_ctf_section_name, dump_ctf_parent_name,
>>  		  dump_ctf_parent_section_name);
>> @@ -6408,6 +6667,12 @@ main (int argc, char **argv)
>>  	  dump_ctf_parent_section_name = xstrdup (optarg);
>>  	  break;
>>  #endif
>> +	case OPTION_BTF:
>> +	  dump_btf_section_info = true;
>> +	  if (optarg)
>> +	    dump_btf_section_name = xstrdup (optarg);
>> +	  seenflag = true;
>> +	  break;
>>  	case OPTION_SFRAME:
>>  	  dump_sframe_section_info = true;