Subject: [OMPI users] Valgrind writev() errors with 1.3.2.
From: tom fogal (tfogal_at_[hidden])
Date: 2009-06-08 15:09:10


Hi all,

I've configured a source build of OpenMPI 1.3.2 with valgrind enabled
[1], and I'm seeing a lot of errors with writev() when I run this under
valgrind. For example, with the following `hello, world' program:

  #include <stdio.h>
  #include <mpi.h>

  int main(int argc, char *argv[]) {
    MPI_Init(&argc, &argv);

    puts("Hello, world!");
    MPI_Finalize();
    return 0;
  }

I see errors like the following:

  ==12342== Syscall param writev(vector[...]) points to uninitialised byte(s)
  ==12342== at 0x61DF733: writev (in /lib/libc-2.7.so)
  ==12342== by 0x7889AB9: mca_oob_tcp_msg_send_handler (oob_tcp_msg.c:265)
  ==12342== by 0x788B1A0: mca_oob_tcp_peer_send (oob_tcp_peer.c:197)
  ==12342== by 0x788FF2A: mca_oob_tcp_send_nb (oob_tcp_send.c:167)
  ==12342== by 0x767C7EC: orte_rml_oob_send (rml_oob_send.c:137)
  ==12342== by 0x767D19A: orte_rml_oob_send_buffer (rml_oob_send.c:269)
  ==12342== by 0x7C9F3DF: allgather (grpcomm_bad_module.c:369)
  ==12342== by 0x7C9FD9E: modex (grpcomm_bad_module.c:497)
  ==12342== by 0x4E6DCAF: ompi_mpi_init (ompi_mpi_init.c:626)

The full vg log is appended [2]. Of course, I could just suppress
this error, but I get this for a lot (every?) MPI call which does
communication, it seems (broadcasts, sends, recv's, allgathers, etc.).
I'm worried a suppression would suppress too much / suppress an error
I've caused.

Have others seen this? Can I suppress perhaps from the
orte_rml_oob_send_buffer down (safely)?

-tom

[1] configured via: gnu_pkg \
    --enable-debug \
    --enable-memchecker \
    --disable-mpi-f77 \
    --enable-pretty-print-stacktrace \
    --enable-cxx-exceptions \
    --enable-mpi-threads \
    --with-valgrind=${PREFIX} \
    --without-gm \
    --without-mx \
    --without-openib \
    --without-psm \
    --with-pic \
    --with-gnu-ld
  where gnu_pkg is basically a function which calls configure with
  --prefix=${PREFIX}.

[2]
==12342== Memcheck, a memory error detector.
==12342== Copyright (C) 2002-2008, and GNU GPL'd, by Julian Seward et al.
==12342== Using LibVEX rev 1884, a library for dynamic binary translation.
==12342== Copyright (C) 2004-2008, and GNU GPL'd, by OpenWorks LLP.
==12342== Using valgrind-3.4.1, a dynamic binary instrumentation framework.
==12342== Copyright (C) 2000-2008, and GNU GPL'd, by Julian Seward et al.
==12342== For more details, rerun with: -v
==12342==
==12342== My PID = 12342, parent PID = 12341. Prog and args are:
==12342== ./a.out
==12342==
==12342== Warning: client syscall munmap tried to modify addresses 0xffffffffffffffff-0xffe
==12342== Syscall param writev(vector[...]) points to uninitialised byte(s)
==12342== at 0x61DF733: writev (in /lib/libc-2.7.so)
==12342== by 0x7889AB9: mca_oob_tcp_msg_send_handler (oob_tcp_msg.c:265)
==12342== by 0x788B1A0: mca_oob_tcp_peer_send (oob_tcp_peer.c:197)
==12342== by 0x788FF2A: mca_oob_tcp_send_nb (oob_tcp_send.c:167)
==12342== by 0x767C7EC: orte_rml_oob_send (rml_oob_send.c:137)
==12342== by 0x767D19A: orte_rml_oob_send_buffer (rml_oob_send.c:269)
==12342== by 0x7C9F3DF: allgather (grpcomm_bad_module.c:369)
==12342== by 0x7C9FD9E: modex (grpcomm_bad_module.c:497)
==12342== by 0x4E6DCAF: ompi_mpi_init (ompi_mpi_init.c:626)
==12342== by 0x4EAAC88: PMPI_Init (pinit.c:80)
==12342== by 0x400857: main (hello.c:5)
==12342== Address 0x677697b is 107 bytes inside a block of size 256 alloc'd
==12342== at 0x4C22A51: realloc (vg_replace_malloc.c:429)
==12342== by 0x53DCBE0: opal_dss_buffer_extend (dss_internal_functions.c:63)
==12342== by 0x53DE4BA: opal_dss_copy_payload (dss_load_unload.c:164)
==12342== by 0x7C9F314: allgather (grpcomm_bad_module.c:363)
==12342== by 0x7C9FD9E: modex (grpcomm_bad_module.c:497)
==12342== by 0x4E6DCAF: ompi_mpi_init (ompi_mpi_init.c:626)
==12342== by 0x4EAAC88: PMPI_Init (pinit.c:80)
==12342== by 0x400857: main (hello.c:5)
==12342== Uninitialised value was created by a stack allocation
==12342== at 0x53FFA60: opal_ifinit (if.c:147)
{
   <insert a suppression name here>
   Memcheck:Param
   writev(vector[...])
   fun:writev
   fun:mca_oob_tcp_msg_send_handler
   fun:mca_oob_tcp_peer_send
   fun:mca_oob_tcp_send_nb
   fun:orte_rml_oob_send
   fun:orte_rml_oob_send_buffer
   fun:allgather
   fun:modex
   fun:ompi_mpi_init
   fun:PMPI_Init
   fun:main
}
==12342==
==12342== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 307 from 3)
==12342== malloc/free: in use at exit: 204,012 bytes in 2,022 blocks.
==12342== malloc/free: 10,382 allocs, 8,360 frees, 14,603,162 bytes allocated.
==12342== For a detailed leak analysis, rerun with: --leak-check=yes
==12342== For counts of detected errors, rerun with: -v