[sr-dev] Kamailio stucks at __read_nocancel during stop.

Hi, We're getting periodically core dumps when stopping Kamailio: GNU gdb (Debian 7.12-6) 7.12.0.20161007-git Copyright (C) 2016 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 "x86_64-linux-gnu". Type "show configuration" for configuration details. For bug reporting instructions, please see: <http://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 /var/lib/ums/sbin/kamailio...done. [New LWP 9832] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Core was generated by `/var/lib/ums/sbin/kamailio -m 2048 -M 12 -P /var/run/kamailio/kamailio.pid -f /'. Program terminated with signal SIGABRT, Aborted. #0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 #0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 #1 0x00007f79c24e842a in __GI_abort () at abort.c:89 #2 0x000000000043f92a in sig_alarm_abort (signo=14) at main.c:679 #3 <signal handler called#4 0x00007f79c258f910 in __read_nocancel () at ../sysdeps/unix/syscall-template.S:84 #5 0x00007f793cbd7421 in vio_read_buff () from /var/lib/ums/lib/mysql/libmysqlclient.so.16 #6 0x00007f793cbd8aa0 in my_real_read () from /var/lib/ums/lib/mysql/libmysqlclient.so.16 #7 0x00007f793cbd87d6 in my_net_read () from /var/lib/ums/lib/mysql/libmysqlclient.so.16 #8 0x00007f793cbd085d in cli_safe_read () from /var/lib/ums/lib/mysql/libmysqlclient.so.16 #9 0x00007f793cbd539a in cli_read_query_result () from /var/lib/ums/lib/mysql/libmysqlclient.so.16 #10 0x00007f793cbd436d in mysql_real_query () from /var/lib/ums/lib/mysql/libmysqlclient.so.16 #11 0x00007f793ce80c13 in db_mysql_submit_query (_h=0x7f79c1786890, _s=0x7f793f379250 <sql_str>) at km_dbase.c:111 #12 0x00007f793f16baba in db_do_submit_query (_h=0x7f79c1786890, _query=0x7f793f379250 <sql_str>, submit_query=0x7f793ce801a0 <db_mysql_submit_query>) at db_query.c:58 #13 0x00007f793f16e114 in db_do_delete (_h=0x7f79c1786890, _k=0x7ffeb3ca8df8, _o=0x0, _v=0x7ffeb3ca8dd0, _n=1, val2str=0x7f793cea8990 <db_mysql_val2str>, submit_query=0x7f793ce801a0 <db_mysql_submit_query>) at db_query.c:300 #14 0x00007f793ce86c17 in db_mysql_delete (_h=0x7f79c1786890, _k=0x7ffeb3ca8df8, _o=0x0, _v=0x7ffeb3ca8dd0, _n=1) at km_dbase.c:510 #15 0x00007f793f3cb841 in db_delete_ucontact_ruid (_c=0x7f794186b3c0) at ucontact.c:1552 #16 0x00007f793f3cd096 in db_delete_ucontact (_c=0x7f794186b3c0) at ucontact.c:1570 #17 0x00007f793f3ad0c0 in wb_timer (_r=0x7f79411d7330) at urecord.c:401 #18 0x00007f793f3ab451 in timer_urecord (_r=0x7f79411d7330) at urecord.c:463 #19 0x00007f793f3978aa in mem_timer_udomain (_d=0x7f7940d9baa0, istart=0, istep=1) at udomain.c:1224 #20 0x00007f793f3d4608 in synchronize_all_udomains (istart=0, istep=1) at dlist.c:756 #21 0x00007f793f3a2768 in destroy () at usrloc_mod.c:464 #22 0x0000000000637e2c in destroy_modules () at core/sr_module.c:746 #23 0x000000000041c4d8 in cleanup (show_status=1) at main.c:555 #24 0x0000000000423af7 in shutdown_children (sig=15, show_status=1) at main.c:696 #25 0x000000000041f081 in handle_sigs () at main.c:727 #26 0x0000000000432a01 in main_loop () at main.c:1806 #27 0x000000000043df6f in main (argc=9, argv=0x7ffeb3cac348) at main.c:2802 Looks like libmysql stucks at __read_nocancel() syscall. The exit_timeout parameter is set by default (60 sec), Kamailio version 5.3.1. Any ideas? Thanks, Andrey