[lttng-dev] LTTNG LIB UST Crash

[Lakshmi Deverkonda]

Hi All,

I am observing lttng crash while trying to interface LTTNG for one of my python3 application.
I just tried the following things,

Added "import lttngust " in the code.

# lttng create clagd
Session clagd created.
Traces will be written in /root/lttng-traces/clagd-20230905-062210

# lttng enable-event --python clagd
#lttng start

#service clagd start

cumulus-core: Running cl-support for core files "clagd-ust.95410.1693895062.core"

#0  0x00007f134fb938eb in raise () from /lib/x86_64-linux-gnu/libc.so.6
#1  0x00007f134fb7e535 in abort () from /lib/x86_64-linux-gnu/libc.so.6
#2  0x00007f134fb7e40f in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#3  0x00007f134fb8c1a2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6
#4  0x00007f134f1a9677 in lttng_ust_add_fd_to_tracker () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#5  0x00007f134f1bdcf4 in lttng_ust_elf_create () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#6  0x00007f134f1bf8de in ?? () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#7  0x00007f134fc8f957 in dl_iterate_phdr () from /lib/x86_64-linux-gnu/libc.so.6
#8  0x00007f134f1bff6b in lttng_ust_dl_update () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#9  0x00007f134f1c061a in do_lttng_ust_statedump () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#10 0x00007f134f1b5ca9 in lttng_handle_pending_statedump () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#11 0x00007f134f1ab6d1 in ?? () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#12 0x00007f134f1ad7eb in ?? () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#13 0x00007f134ff0dfa3 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0
#14 0x00007f134fc5506f in clone () from /lib/x86_64-linux-gnu/libc.so.6


When I stop the lttng session, I see another core

#0  0x00007fad951988eb in raise () from /lib/x86_64-linux-gnu/libc.so.6
[Current thread is 1 (Thread 0x7fad9331f700 (LWP 2221103))]
(gdb) bt
#0  0x00007fad951988eb in raise () from /lib/x86_64-linux-gnu/libc.so.6
#1  0x00007fad95183535 in abort () from /lib/x86_64-linux-gnu/libc.so.6
#2  0x00007fad9518340f in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#3  0x00007fad951911a2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6
#4  0x00007fad947e8d9f in ?? () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#5  0x00007fad947e98e3 in shm_object_table_destroy () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#6  0x00007fad947e4d9a in channel_destroy () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#7  0x00007fad947ba6b5 in lttng_session_destroy () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#8  0x00007fad947b47c6 in ?? () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#9  0x00007fad947b4bac in lttng_ust_objd_unref () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#10 0x00007fad947b4bac in lttng_ust_objd_unref () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#11 0x00007fad947b4bac in lttng_ust_objd_unref () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#12 0x00007fad947b5304 in lttng_ust_objd_table_owner_cleanup () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#13 0x00007fad947b2b75 in ?? () from /lib/x86_64-linux-gnu/liblttng-ust.so.0
#14 0x00007fad95512fa3 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0
#15 0x00007fad9525a06f in clone () from /lib/x86_64-linux-gnu/libc.so.6


Can you please help here if I'm missing something. This is a critical task item for us but are currently stuck with multiple lttng crashes.

Regards,
Lakshmi
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.lttng.org/pipermail/lttng-dev/attachments/20230905/63dc6f67/attachment.htm>