Re: armv7 main's gpart [show]: signal 11 core dump during boot, before login; xo_format_string_direct; official pkgbase distribution (kernel and world)

From: Mark Millard <marklmi_at_yahoo.com>
Date: Sun, 28 Dec 2025 08:23:12 UTC
On Dec 27, 2025, at 23:55, Mark Millard <marklmi@yahoo.com> wrote:

> [Turns out: works on aarch64 kernel's armv7 support, fails
> on the armv7 native kernel, exact same world files on the
> exact same media.]

I got that wrong: a large part of the output occurs before a
segmentation fault on the Windows Dev Kit 2023. But it has a
very different backtrace and the output before that has numerical
garbage values showing.

> 
> On Dec 27, 2025, at 23:35, Mark Millard <marklmi@yahoo.com> wrote:
> 
>> On Dec 27, 2025, at 22:03, Mark Millard <marklmi@yahoo.com> wrote:
>> 
>>> Context:
>>> 
>>> # uname -apKU
>>> FreeBSD OPiP2E-RPi2v1p1 16.0-CURRENT FreeBSD 16.0-CURRENT main-n282732-939ac0c8fde2 GENERIC-NODEBUG arm armv7 1600007 1600007
>>> 
>>> That is an official pkgbase distribution that I installed, not
>>> a personal build. pkgbase for main has world being a debug
>>> build, no matter which of the kernels one choses to boot.
>>> For pkgbase, 939ac0c8fde2 would be correct(?) for the kernel
>>> but might not be exact for the world: /usr/src/sys/ and
>>> /usr/src/ (without sys/) are from different times, last I
>>> knew anyway. Changes can happen between.
>>> 
>>> During boot, the time on the Orange Pi Plus 2ed is bad so:
>>> 
>>> # ls -lodT /gpart.core 
>>> -rw-------  1 root wheel nodump 3174400 Jan  1 00:01:01 2010 /gpart.core
>>> 
>>> Also, for pkgbase, a source file distributed can be newer
>>> for its time stamp than the program distributed that was
>>> based on the source file. Such happens below.
>>> 
>>> 
>>> 
>>> Core was generated by `gpart show'.
>>> Program terminated with signal SIGSEGV, Segmentation fault.
>>> Address not mapped to object.
>>> #0  xo_format_string_direct (xop=xop@entry=0x2009b120, xbp=xbp@entry=0x2009b150, flags=flags@entry=4096, wcp=0x0, cp=0x6e480000 <error: Cannot access memory at address 0x6e480000>, len=-1, max=-1, 
>>>  need_enc=3, have_enc=2) at /usr/src/contrib/libxo/libxo/libxo.c:2715
>>> 
>>> warning: Source file is more recent than executable.
>>> 2715    if (*cp == '\0')
>>> (gdb) bt
>>> #0  xo_format_string_direct (xop=xop@entry=0x2009b120, xbp=xbp@entry=0x2009b150, flags=flags@entry=4096, wcp=0x0, cp=0x6e480000 <error: Cannot access memory at address 0x6e480000>, len=-1, max=-1, 
>>>  need_enc=3, have_enc=2) at /usr/src/contrib/libxo/libxo/libxo.c:2715
>>> #1  0x20150908 in xo_format_string (xop=0x2009b120, xbp=0x2009b150, flags=4096, xfp=0xbfbfd280) at /usr/src/contrib/libxo/libxo/libxo.c:2982
>>> #2  xo_do_format_field (xop=<optimized out>, xop@entry=0x2009b120, xbp=0x2009b150, fmt=fmt@entry=0x20130635 "%s", flen=flen@entry=2, flags=4096) at /usr/src/contrib/libxo/libxo/libxo.c:3503
>>> #3  0x2014c69c in xo_simple_field (xop=0x2009b120, encode_only=0, value=0x0, vlen=0, fmt=0x20130635 "%s", flen=2, flags=<optimized out>) at /usr/src/contrib/libxo/libxo/libxo.c:3817
>>> #4  xo_format_value (xop=<optimized out>, xop@entry=0x2009b120, name=<optimized out>, name@entry=0x204bf931 "state}\n", nlen=<optimized out>, nlen@entry=5, value=0x0, vlen=0, fmt=0x20130635 "%s", 
>>>  flen=2, encoding=0x0, elen=0, flags=<optimized out>) at /usr/src/contrib/libxo/libxo/libxo.c:4373
>>> #5  0x20148710 in xo_do_emit_fields (xop=<optimized out>, xop@entry=0x2009b120, fields=<optimized out>, fields@entry=0xbfbfd7e8, max_fields=max_fields@entry=17, fmt=<optimized out>)
>>>  at /usr/src/contrib/libxo/libxo/libxo.c:6372
>>> #6  0x201476a0 in xo_do_emit (xop=xop@entry=0x2009b120, flags=<optimized out>, fmt=fmt@entry=0x204bf8e3 "=>{t:start/%*jd}  {t:sectors/%*jd}  {t:name/%*s}  {:scheme}  ({h:size/%ld}){t:state}\n")
>>>  at /usr/src/contrib/libxo/libxo/libxo.c:6551
>>> #7  0x20147840 in xo_emit (fmt=0x204bf8e3 "=>{t:start/%*jd}  {t:sectors/%*jd}  {t:name/%*s}  {:scheme}  ({h:size/%ld}){t:state}\n") at /usr/src/contrib/libxo/libxo/libxo.c:6622
>>> #8  0x204d1fd4 in gpart_show_geom (gp=gp@entry=0x20089168, element=element@entry=0x204bfe51 "type", show_providers=show_providers@entry=0) at /usr/src/lib/geom/part/geom_part.c:654
>>> #9  0x204d1048 in gpart_show (req=0x20089000, fl=<optimized out>) at /usr/src/lib/geom/part/geom_part.c:793
>>> #10 0x000230dc in run_command (argc=0, argv=<optimized out>) at /usr/src/sbin/geom/core/geom.c:497
>>> #11 0x00022308 in main (argc=1, argv=0xbfbfed90) at /usr/src/sbin/geom/core/geom.c:861
>>> (gdb) list
>>> 2710    for (;;) {
>>> 2711 if (len == 0)
>>> 2712    break;
>>> 2713 
>>> 2714 if (cp) {
>>> 2715    if (*cp == '\0')
>>> 2716 break;
>>> 2717    if ((flags & XFF_UNESCAPE) && (*cp == '\\' || *cp == '%')) {
>>> 2718 cp += 1;
>>> 2719 len -= 1;
>>> (gdb) up
>>> #1  0x20150908 in xo_format_string (xop=0x2009b120, xbp=0x2009b150, flags=4096, xfp=0xbfbfd280) at /usr/src/contrib/libxo/libxo/libxo.c:2982
>>> 2982    cols = xo_format_string_direct(xop, xbp, flags, wcp, cp, len,
>>> (gdb) list
>>> 2977 
>>> 2978    return rc;
>>> 2979 }
>>> 2980    }
>>> 2981 
>>> 2982    cols = xo_format_string_direct(xop, xbp, flags, wcp, cp, len,
>>> 2983   xfp->xf_width[XF_WIDTH_MAX],
>>> 2984   need_enc, xfp->xf_enc);
>>> 2985    if (cols < 0)
>>> 2986 goto bail;
>>> (gdb) list
>>> 3498 
>>> 3499 xf.xf_enc = (xf.xf_fc == 'm') ? XF_ENC_UTF8
>>> 3500    : (xf.xf_lflag || (xf.xf_fc == 'S')) ? XF_ENC_WIDE
>>> 3501    : xf.xf_hflag ? XF_ENC_LOCALE : XF_ENC_UTF8;
>>> 3502 
>>> 3503 rc = xo_format_string(xop, xbp, flags, &xf);
>>> 3504 
>>> 3505 if ((flags & XFF_TRIM_WS) && xo_style_is_encoding(xop))
>>> 3506    rc = xo_trim_ws(xbp, rc);
>>> 3507 
>>> (gdb) up
>>> #3  0x2014c69c in xo_simple_field (xop=0x2009b120, encode_only=0, value=0x0, vlen=0, fmt=0x20130635 "%s", flen=2, flags=<optimized out>) at /usr/src/contrib/libxo/libxo/libxo.c:3817
>>> 3817 xo_do_format_field(xop, NULL, fmt, flen, flags);
>>> (gdb) list
>>> 3812 {
>>> 3813    if (encode_only)
>>> 3814 flags |= XFF_NO_OUTPUT;
>>> 3815 
>>> 3816    if (vlen == 0)
>>> 3817 xo_do_format_field(xop, NULL, fmt, flen, flags);
>>> 3818    else if (!encode_only)
>>> 3819 xo_data_append_content(xop, value, vlen, flags);
>>> 3820 }
>>> 3821 
>>> (gdb) up
>>> #4  xo_format_value (xop=<optimized out>, xop@entry=0x2009b120, name=<optimized out>, name@entry=0x204bf931 "state}\n", nlen=<optimized out>, nlen@entry=5, value=0x0, vlen=0, fmt=0x20130635 "%s", 
>>>  flen=2, encoding=0x0, elen=0, flags=<optimized out>) at /usr/src/contrib/libxo/libxo/libxo.c:4373
>>> 4373 xo_simple_field(xop, FALSE, value, vlen, fmt, flen, flags);
>>> (gdb) list
>>> 4368 
>>> 4369 save.xhs_offset = xbp->xb_curp - xbp->xb_bufp;
>>> 4370 save.xhs_columns = xop->xo_columns;
>>> 4371 save.xhs_anchor_columns = xop->xo_anchor_columns;
>>> 4372 
>>> 4373 xo_simple_field(xop, FALSE, value, vlen, fmt, flen, flags);
>>> 4374 
>>> 4375 if (flags & XFF_HUMANIZE)
>>> 4376    xo_format_humanize(xop, xbp, &save, flags);
>>> 4377 break;
>>> (gdb) up
>>> #5  0x20148710 in xo_do_emit_fields (xop=<optimized out>, xop@entry=0x2009b120, fields=<optimized out>, fields@entry=0xbfbfd7e8, max_fields=max_fields@entry=17, fmt=<optimized out>)
>>>  at /usr/src/contrib/libxo/libxo/libxo.c:6372
>>> 6372    xo_format_value(xop, content, clen, NULL, 0,
>>> (gdb) list
>>> 6367 flags &= ~XFF_WS; /* Prevent later handling of this flag */
>>> 6368    }
>>> 6369 }
>>> 6370 
>>> 6371 if (ftype == 'V')
>>> 6372    xo_format_value(xop, content, clen, NULL, 0,
>>> 6373    xfip->xfi_format, xfip->xfi_flen,
>>> 6374    xfip->xfi_encoding, xfip->xfi_elen, flags);
>>> 6375 else if (ftype == '[')
>>> 6376    xo_anchor_start(xop, xfip, content, clen);
>>> (gdb) up
>>> #6  0x201476a0 in xo_do_emit (xop=xop@entry=0x2009b120, flags=<optimized out>, fmt=fmt@entry=0x204bf8e3 "=>{t:start/%*jd}  {t:sectors/%*jd}  {t:name/%*s}  {:scheme}  ({h:size/%ld}){t:state}\n")
>>>  at /usr/src/contrib/libxo/libxo/libxo.c:6551
>>> 6551    return xo_do_emit_fields(xop, fields, max_fields, fmt);
>>> (gdb) list
>>> 6546    /* Retain the info */
>>> 6547    xo_retain_add(fmt, fields, max_fields);
>>> 6548 }
>>> 6549    }
>>> 6550 
>>> 6551    return xo_do_emit_fields(xop, fields, max_fields, fmt);
>>> 6552 }
>>> 6553 
>>> 6554 /*
>>> 6555 * Rebuild a format string in a gettext-friendly format.  This function
>>> (gdb) up
>>> #7  0x20147840 in xo_emit (fmt=0x204bf8e3 "=>{t:start/%*jd}  {t:sectors/%*jd}  {t:name/%*s}  {:scheme}  ({h:size/%ld}){t:state}\n") at /usr/src/contrib/libxo/libxo/libxo.c:6622
>>> 6622    rc = xo_do_emit(xop, 0, fmt);
>>> (gdb) list
>>> 6617 {
>>> 6618    xo_handle_t *xop = xo_default(NULL);
>>> 6619    ssize_t rc;
>>> 6620 
>>> 6621    va_start(xop->xo_vap, fmt);
>>> 6622    rc = xo_do_emit(xop, 0, fmt);
>>> 6623    va_end(xop->xo_vap);
>>> 6624    bzero(&xop->xo_vap, sizeof(xop->xo_vap));
>>> 6625 
>>> 6626    return rc;
>>> (gdb) up
>>> #8  0x204d1fd4 in gpart_show_geom (gp=gp@entry=0x20089168, element=element@entry=0x204bfe51 "type", show_providers=show_providers@entry=0) at /usr/src/lib/geom/part/geom_part.c:654
>>> warning: Source file is more recent than executable.
>>> 654 xo_emit("=>{t:start/%*jd}  {t:sectors/%*jd}  {t:name/%*s}  {:scheme}  ({h:size/%ld}){t:state}\n",
>>> (gdb) list
>>> 649 }
>>> 650 wname = wmax;
>>> 651 pp = LIST_FIRST(&gp->lg_consumer)->lg_provider;
>>> 652 secsz = pp->lg_sectorsize;
>>> 653 xo_open_instance("part");
>>> 654 xo_emit("=>{t:start/%*jd}  {t:sectors/%*jd}  {t:name/%*s}  {:scheme}  ({h:size/%ld}){t:state}\n",
>>> 655 wblocks, (intmax_t)first, wblocks, (intmax_t)(last - first + 1),
>>> 656 wname, gp->lg_name,
>>> 657 scheme, pp->lg_mediasize,
>>> 658 s ? " [CORRUPT]": "");
>>> (gdb) up
>>> #9  0x204d1048 in gpart_show (req=0x20089000, fl=<optimized out>) at /usr/src/lib/geom/part/geom_part.c:793
>>> 793 gpart_show_geom(gp, element, show_providers);
>>> (gdb) list
>>> 788 else
>>> 789 errx(EXIT_FAILURE, "No such geom: %s.", name);
>>> 790 }
>>> 791 } else {
>>> 792 LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
>>> 793 gpart_show_geom(gp, element, show_providers);
>>> 794 }
>>> 795 }
>>> 796 xo_close_list(name);
>>> 797 geom_deletetree(&mesh);
>>> (gdb) up
>>> #10 0x000230dc in run_command (argc=0, argv=<optimized out>) at /usr/src/sbin/geom/core/geom.c:497
>>> warning: Source file is more recent than executable.
>>> 497 cmd->gc_func(req, flags);
>>> (gdb) list
>>> 492 buf[0] = '\0';
>>> 493 if (cmd->gc_func != NULL) {
>>> 494 unsigned flags;
>>> 495 
>>> 496 flags = set_flags(cmd);
>>> 497 cmd->gc_func(req, flags);
>>> 498 errstr = req->error;
>>> 499 } else {
>>> 500 gctl_add_param(req, "output", sizeof(buf), buf,
>>> 501    GCTL_PARAM_WR | GCTL_PARAM_ASCII);
>>> (gdb) up
>>> #11 0x00022308 in main (argc=1, argv=0xbfbfed90) at /usr/src/sbin/geom/core/geom.c:861
>>> 861 run_command(argc, argv);
>>> (gdb) list
>>> 856 show_tree();
>>> 857 return (0);
>>> 858 }
>>> 859 
>>> 860 get_class(&argc, &argv);
>>> 861 run_command(argc, argv);
>>> 862 /* NOTREACHED */
>>> 863 
>>> 864 exit(EXIT_FAILURE);
>>> 865 }
>>> 
>>> 
>>> For reference:
>>> 
>>> # ls -lodT /usr/src/contrib/libxo/libxo/libxo.c /usr/src/lib/geom/part/geom_part.c /usr/src/sbin/geom/core/geom.c /sbin/gpart
>>> -r-xr-xr-x  17 root wheel -  30720 Dec 18 07:22:59 2025 /sbin/gpart
>>> -rw-r--r--   1 root wheel - 211505 Dec 24 08:29:29 2025 /usr/src/contrib/libxo/libxo/libxo.c
>>> -rw-r--r--   1 root wheel -  35380 Dec 24 08:29:29 2025 /usr/src/lib/geom/part/geom_part.c
>>> -rw-r--r--   1 root wheel -  36298 Dec 24 08:29:29 2025 /usr/src/sbin/geom/core/geom.c
>>> 
>>> That explains the "warning: Source file is more recent than executable"
>>> messages.
>> 
>> Additional context notes:
>> 
>> ) On the Cortex-A7 SUT the above is repeatable at the
>>  shell prompt when logged in: just try "gpart show",
>>  including via gdb use. "/rescue/gpart show" also
>>  core dumps.
>> 
>> ) In a armv7 chroot on a aarch64 system (the Windows
>>  Dev Kit 2023), the "gpart show" works just fine.
>> 
>> But the vintages could well be a little different.
>> (Tracing to git commits for pkgbase is problematical.)
>> 
>> 
>> I'll note:
>> 
>> Johan Söllvander <js_at_FreeBSD.org>
>> Date: Thu, 18 Dec 2025 15:23:29 UTC 
>> The branch main has been updated by js:
>> 
>> URL: https://cgit.FreeBSD.org/src/commit/?id=4f809ffec69cd6ede3e7be9a5bc876b2e5931028
>> 
>> commit 4f809ffec69cd6ede3e7be9a5bc876b2e5931028
>> Author: Johan Söllvander <js@FreeBSD.org>
>> AuthorDate: 2025-12-18 15:06:09 +0000
>> Commit: Johan Söllvander <js@FreeBSD.org>
>> CommitDate: 2025-12-18 15:22:59 +0000
>> 
>> gpart: add libxo support for "show" subcommand + man page updates
>> 
>> Added libxo support to `gpart show`, also updated the man
>> pages for geom and gpart to show where you can expect
>> libxo formatted output.
>> 
>> PR: 290629
>> MFC after: 1 week
>> Sponsored by: ConnectWise
>> Reviewed by: asomers, mckusick, phil
>> Approved by: asomers (mentor)
>> Differential Revision: https://reviews.freebsd.org/D53950
>> ---
>> . . .
>> 
>> 
>> Note: Dec 18 07:22:59 2025 /sbin/gpart for my time zone
>> would be 2025-12-18 15:22:59 +0000 (the CommitDate) UTC.
> 
> 
> I shut down the OPi+2e and mounted the boot media
> on the Windows Dev Kit 2023 and then did a chroot
> into that boot media and tried "gpart show":
> 
> "gpart show" worked just fine.
> 
> What matters is which kernel it runs on for the
> exact same world files on the exact same media.
> 

I got that wrong: a large part of the output occurs before
a segmentation fault on the Windows Dev Kit 2023. But it has a
very different backtrace. Also, note all the "517M" that make no
sense --and the "0" and "2" junk as well:

# gpart show 
=>        34  1000215149  nda0  GPT  (2)(null)
          34        2014        - free -  (2)
        2048      532480     1  efi  (517M)
      534528       32768     2  ms-reserved  (517M)
      567296   997287936     3  ms-basic-data  (517M)
   997855232     2359296     4  ms-recovery  (517M)
  1000214528         655        - free -  (2)

=>        34  2930277101  da0  GPT  (0)(null)
          34       32734       - free -  (0)
       32768      501760    1  efi  (517M)
      534528    20971520    2  freebsd-swap  (517M)
    21506048    29360128    3  freebsd-swap  (517M)
    50866176    33554432    4  freebsd-swap  (517M)
    84420608    67108864    5  freebsd-swap  (517M)
   151529472    96468992    6  freebsd-swap  (517M)
   247998464   268435456    7  freebsd-swap  (517M)
   516433920     7340032    8  freebsd-swap  (517M)
   523773952    13096960       - free -  (0)
   536870912  2357198848    9  freebsd-ufs  (517M)
  2894069760    36207375       - free -  (0)

=>        40  1953525088  da1  GPT  (0)(null)
          40      532480    1  efi  (517M)
      532520        2008       - free -  (0)
      534528     3563520    2  freebsd-swap  (517M)
     4098048     6504448       - free -  (0)
    10602496  1740636160    4  freebsd-ufs  (517M)
  1751238656     7546880    3  freebsd-swap  (517M)
  1758785536   194739592       - free -  (0)

Segmentation fault (core dumped)

As for gdb's backtrace:

Program terminated with signal SIGSEGV, Segmentation fault.
Address not mapped to object.
#0  0x200c5ef0 in delete_config (gp=0x2053e224) at /usr/src/lib/libgeom/geom_xml2tree.c:502

warning: Source file is more recent than executable.
502 LIST_REMOVE(cf, lg_config);
(gdb) bt
#0  0x200c5ef0 in delete_config (gp=0x2053e224) at /usr/src/lib/libgeom/geom_xml2tree.c:502
#1  geom_deletetree (gmp=gmp@entry=0xffffcb48) at /usr/src/lib/libgeom/geom_xml2tree.c:524
#2  0x204d2064 in gpart_show (req=<optimized out>, fl=<optimized out>) at /usr/src/lib/geom/part/geom_part.c:797
#3  0x000230dc in run_command (argc=0, argv=<optimized out>) at /usr/src/sbin/geom/core/geom.c:497
#4  0x00022308 in main (argc=1, argv=0xffffdc70) at /usr/src/sbin/geom/core/geom.c:861


(I need to get some sleep.)


===
Mark Millard
marklmi at yahoo.com