This is a bit convoluted, but hang in there.
So there is this bug: http://developerbugs.linux-foundation.org/show_bug.cgi?id=2379 Essentially, to reproduce, you stop syslog but leave it enabled in corosync.conf. Here is the logging section I used: logging { debug: on fileline: off to_syslog: yes to_stderr: no to_logfile: yes logfile: /tmp/corosync.log syslog_facility: daemon timestamp: on } What would happen is that on startup, the (pacemaker) child processes would deadlock _inside_ the call to fork(). This seemed to happen more often if the logfile didnt yet exist. Here's the gdb stack trace: #0 0x0000003268407bfd in pthread_join (threadid=140599098124048, thread_return=0x0) at pthread_join.c:89 #1 0x0000000000406805 in sigsegv_handler (num=<value optimized out>) at main.c:212 #2 <signal handler called> #3 fresetlockfiles () at ../nptl/sysdeps/unix/sysv/linux/fork.c:48 #4 __libc_fork () at ../nptl/sysdeps/unix/sysv/linux/fork.c:158 #5 0x00007fdfc5d95772 in spawn_child () from /usr/libexec/lcrso/pacemaker.lcrso #6 0x00007fdfc5d99e4a in pcmk_startup () from /usr/libexec/lcrso/pacemaker.lcrso #7 0x0000000000407f23 in corosync_service_link_and_init (corosync_api=0x613c40, service_name=0x1020430 "pacemaker", service_ver=<value optimized out>) at service.c:201 #8 0x00000000004082c1 in corosync_service_defaults_link_and_init (corosync_api=0x613c40) at service.c:535 #9 0x0000000000405df6 in main_service_ready () at main.c:1204 #10 0x000000326e00f81f in main_iface_change_fn (context=0x7fdfc6027010, iface_addr=<value optimized out>, iface_no=<value optimized out>) at totemsrp.c:4347 #11 0x000000326e009f7a in timer_function_netif_check_timeout (data=0x10474d0) at totemudp.c:1359 #12 0x000000326e006709 in timerlist_expire (handle=1197105576937521152) at tlist.h:309 #13 poll_run (handle=1197105576937521152) at coropoll.c:409 #14 0x000000000040568b in main (argc=<value optimized out>, argv=<value optimized out>) at main.c:1556 As I see it, there are three problems here. 1) fork() is segfaulting 2) sigsegv_handler() is doing _WAY_ too much. I don't believe it should be calling logsys_atexit() - certainly not if logsys_atexit() then calls pthread_join 3) logsys_atexit() is calling pthread_join() on a thread that doesn't exist in the new process I'll leave 2) and 3) for someone more knowledgeable. I investigated 1) as the other two don't matter if fork() isn't segfaulting. I tried running valgrind and every fork produced the same complaint: ==00:00:00:03.081 23392== Invalid write of size 4 ==00:00:00:03.082 23392== at 0x3267CA4E72: fork (fork.c:48) ==00:00:00:03.082 23392== by 0x7633771: spawn_child (in /usr/libexec/lcrso/pacemaker.lcrso) ==00:00:00:03.082 23392== by 0x7637E49: pcmk_startup (in /usr/libexec/lcrso/pacemaker.lcrso) ==00:00:00:03.082 23392== by 0x407E07: corosync_service_link_and_init (service.c:201) ==00:00:00:03.082 23392== by 0x4081A0: corosync_service_defaults_link_and_init (service.c:534) ==00:00:00:03.082 23392== by 0x405C85: main_service_ready (main.c:1211) ==00:00:00:03.082 23392== by 0x4C4B2BE: main_iface_change_fn (totemsrp.c:4363) ==00:00:00:03.082 23392== by 0x4C42AD9: timer_function_netif_check_timeout (totemudp.c:1380) ==00:00:00:03.082 23392== by 0x4C3F8DC: poll_run (tlist.h:309) ==00:00:00:03.082 23392== by 0x405543: main (main.c:1563) ==00:00:00:03.082 23392== Address 0x0 is not stack'd, malloc'd or (recently) free'd Note that this is the same file and line that gdb reported. And if you look at line 48 of ./nptl/sysdeps/unix/sysv/linux/fork.c, you see that its the body of this for-loop static void fresetlockfiles (void) { _IO_ITER i; for (i = _IO_iter_begin(); i != _IO_iter_end(); i = _IO_iter_next(i)) _IO_lock_init (*((_IO_lock_t *) _IO_iter_file(i)->_lock)); } I tracking down _IO_iter_begin() which led me to _IO_list_all, which led me to _IO_2_1_stderr_, which led me to test the following patch: Index: exec/main.c =================================================================== --- exec/main.c (revision 2943) +++ exec/main.c (working copy) @@ -418,6 +418,9 @@ fd = open("/dev/null", O_RDWR); if (fd >= 0) { /* dup2 to 0 / 1 / 2 (stdin / stdout / stderr) */ + close (STDIN_FILENO); + close (STDOUT_FILENO); + close (STDERR_FILENO); dup2(fd, STDIN_FILENO); /* 0 */ dup2(fd, STDOUT_FILENO); /* 1 */ dup2(fd, STDERR_FILENO); /* 2 */ With the patch I've not been able to reproduce the hang and valgrind no longer complains. So I'm reasonably certain its the correct fix. Please ACK. _______________________________________________ Openais mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/openais
