port-evbarm/60085: Core dump in libexec/ld.elf_so/t_dlclose_thread test on Pi0W

["jspath55%gmail.com@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60085
>Category:       port-evbarm
>Synopsis:       Core dump in libexec/ld.elf_so/t_dlclose_thread test on Pi0W
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-evbarm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Mar 15 15:50:00 +0000 2026
>Originator:     Jim Spath
>Release:        11.0_RC2
>Organization:
None.
>Environment:
NetBSD rpi 11.0_RC2 NetBSD 11.0_RC2 (RPI) #0: Wed Mar  4 21:02:00 UTC 2026  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/evbarm/compile/RPI evbar
>Description:
Running the ATF test suite, got occasional core dumps with gdb launch. Didn't see this in BETA tests, but several on RC1 and now one with RC2.

End of ATF log:
...
tp-start: 1773446938.192654, libexec/ld.elf_so/t_dlclose_thread, 1
tc-start: 1773446938.194107, dlclose_thread
tc-se:Test program crashed; attempting to get stack trace

Resulting GDB process (still running):
root     9683 86.7  5.9 39396 27260 ?     Rl   12:09AM 1118:41.00 gdb -batch -q -ex bt libexec/ld.elf_so/t_dlclose_thread /tmp/atf-run.IWIv1h/t_dlclose_thread.core 

# pwd
/tmp/atf-run.IWIv1h
# ls -l 
total 704
-rw-r--r--  1 root  wheel  247906 Mar 15 15:40 gdb.out
-rw-------  1 root  wheel  470676 Mar 14 00:09 t_dlclose_thread.core

gdb.out:
[New process 9303]
[New process 10514]
[New process 2247]
[New process 22122]
[New process 4469]
[New process 23516]
[New process 14402]
Core was generated by `t_dlclose_thread'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x7bc2a96c in _rtld_bind () from /usr/libexec/ld.elf_so
[Current thread is 1 (process 9303)]
#0  0x7bc2a96c in _rtld_bind () from /usr/libexec/ld.elf_so
#1  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#2  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#3  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#4  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
...

#3655 0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#3656 0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#3657 0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
(still running)


Attempted gdb trace:

# gdb /usr/tests/libexec/ld.elf_so/t_dlclose_thread t_dlclose_thread.core 
GNU gdb (GDB) 15.1
Copyright (C) 2024 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "armv7--netbsdelf-eabihf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /usr/tests/libexec/ld.elf_so/t_dlclose_thread...
(No debugging symbols found in /usr/tests/libexec/ld.elf_so/t_dlclose_thread)
[New process 9303]
[New process 10514]
[New process 2247]
[New process 22122]
[New process 4469]
[New process 23516]
[New process 14402]
Core was generated by `t_dlclose_thread'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x7bc2a96c in _rtld_bind () from /usr/libexec/ld.elf_so
[Current thread is 1 (process 9303)]
(gdb) bt
#0  0x7bc2a96c in _rtld_bind () from /usr/libexec/ld.elf_so
#1  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#2  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
#3  0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
...
#38 0x7bc2a53c in _rtld_bind_start () from /usr/libexec/ld.elf_so
--Type <RET> for more, q to quit, c to continue without paging--


>How-To-Repeat:
Intermittently happens during atf runs. 3 runs with no fault, and the last one has a crash.
-rw-r--r--  1 root  wheel  12318638 Mar 11 05:46 /root/tests-rpi-202603102242.log
-rw-r--r--  1 root  wheel  12327994 Mar 12 05:45 /root/tests-rpi-202603112242.log
-rw-r--r--  1 root  wheel  12325648 Mar 13 05:46 /root/tests-rpi-202603122242.log
-rw-r--r--  1 root  wheel   2200327 Mar 14 00:09 /root/tests-rpi-202603132242.log

>Fix:
Unknown.