[Qemu-devel] [Bug 668799] Re: qemu-arm segfaults executing msgmerge (gettext)

[Jan-Simon Möller]

Alternative testcase:
compile and "export OMP_NUM_THREADS=6" before running.


/******************************************************************************
* FILE: omp_mm.c
* DESCRIPTION:  
*   OpenMp Example - Matrix Multiply - C Version
*   Demonstrates a matrix multiply using OpenMP. Threads share row iterations
*   according to a predefined chunk size.
* AUTHOR: Blaise Barney
* LAST REVISED: 06/28/05
******************************************************************************/
#include <omp.h>
#include <stdio.h>
#include <stdlib.h>

#define NRA 620                 /* number of rows in matrix A */
#define NCA 150                 /* number of columns in matrix A */
#define NCB 70                  /* number of columns in matrix B */

int main (int argc, char *argv[]) 
{
int     tid, nthreads, i, j, k, chunk;
double  a[NRA][NCA],           /* matrix A to be multiplied */
        b[NCA][NCB],           /* matrix B to be multiplied */
        c[NRA][NCB];           /* result matrix C */

chunk = 10;                    /* set loop iteration chunk size */

/*** Spawn a parallel region explicitly scoping all variables ***/
#pragma omp parallel shared(a,b,c,nthreads,chunk) private(tid,i,j,k)
  {
  tid = omp_get_thread_num();
  if (tid == 0)
    {
    nthreads = omp_get_num_threads();
    printf("Starting matrix multiple example with %d threads\n",nthreads);
    printf("Initializing matrices...\n");
    }
  /*** Initialize matrices ***/
  #pragma omp for schedule (static, chunk) 
  for (i=0; i<NRA; i++)
    for (j=0; j<NCA; j++)
      a[i][j]= i+j;
  #pragma omp for schedule (static, chunk)
  for (i=0; i<NCA; i++)
    for (j=0; j<NCB; j++)
      b[i][j]= i*j;
  #pragma omp for schedule (static, chunk)
  for (i=0; i<NRA; i++)
    for (j=0; j<NCB; j++)
      c[i][j]= 0;

  /*** Do matrix multiply sharing iterations on outer loop ***/
  /*** Display who does which iterations for demonstration purposes ***/
  printf("Thread %d starting matrix multiply...\n",tid);
  #pragma omp for schedule (static, chunk)
  for (i=0; i<NRA; i++)    
    {
    printf("Thread=%d did row=%d\n",tid,i);
    for(j=0; j<NCB; j++)       
      for (k=0; k<NCA; k++)
        c[i][j] += a[i][k] * b[k][j];
    }
  }   /*** End of parallel region ***/

/*** Print results ***/
printf("******************************************************\n");
printf("Result Matrix:\n");
for (i=0; i<NRA; i++)
  {
  for (j=0; j<NCB; j++) 
    printf("%6.2f   ", c[i][j]);
  printf("\n"); 
  }
printf("******************************************************\n");
printf ("Done.\n");

}

-- 
qemu-arm segfaults executing msgmerge (gettext)
https://bugs.launchpad.net/bugs/668799
You received this bug notification because you are a member of qemu-
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Status in QEMU: New

Bug description:
upstream qemu.git revision b45e9c05dbacba8e992f0bffeca04c6379c3ad45

Starting program: /usr/bin/qemu-arm msgmerge-static ar.po anjuta.pot

[Thread debugging using libthread_db enabled]
[New Thread 0x7ffff4bc3ff0 (LWP 26108)]
[New Thread 0x7ffff4b8aff0 (LWP 26109)]
[New Thread 0x7ffff4b51ff0 (LWP 26110)]
[New Thread 0x7ffff4b18ff0 (LWP 26111)]
[New Thread 0x7ffff4adfff0 (LWP 26112)]
[New Thread 0x7ffff4aa6ff0 (LWP 26113)]
[New Thread 0x7ffff4a6dff0 (LWP 26114)]
[New Thread 0x7ffff4a34ff0 (LWP 26115)]
[New Thread 0x7ffff49fbff0 (LWP 26116)]
[New Thread 0x7ffff49c2ff0 (LWP 26117)]
[New Thread 0x7ffff4989ff0 (LWP 26118)]
[New Thread 0x7ffff4950ff0 (LWP 26119)]
[New Thread 0x7ffff4917ff0 (LWP 26120)]
[New Thread 0x7ffff48deff0 (LWP 26121)]
[New Thread 0x7ffff48a5ff0 (LWP 26122)]
[New Thread 0x7ffff486cff0 (LWP 26123)]
[New Thread 0x7ffff4833ff0 (LWP 26124)]
[New Thread 0x7ffff47faff0 (LWP 26125)]
[New Thread 0x7ffff47c1ff0 (LWP 26126)]
[New Thread 0x7ffff4788ff0 (LWP 26127)]
[New Thread 0x7ffff474fff0 (LWP 26128)]
[New Thread 0x7ffff4716ff0 (LWP 26129)]
[New Thread 0x7ffff46ddff0 (LWP 26130)]
.........................
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffff4aa6ff0 (LWP 26113)]
0x00000000600480d4 in tb_reset_jump_recursive2 (tb=0x7ffff4c63540, n=0)
    at /home/user/git/qemu/exec.c:1333
1333                tb1 = tb1->jmp_next[n1];

(gdb) bt
#0  0x00000000600480d4 in tb_reset_jump_recursive2 (tb=0x7ffff4c63540, n=0)
    at /home/user/git/qemu/exec.c:1333
#1  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c63540)
    at /home/user/git/qemu/exec.c:1361
#2  0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c634d8, n=0)
    at /home/user/git/qemu/exec.c:1355
#3  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c634d8)
    at /home/user/git/qemu/exec.c:1361
#4  0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c63470, n=0)
    at /home/user/git/qemu/exec.c:1355
#5  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c63470)
    at /home/user/git/qemu/exec.c:1361
#6  0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c63408, n=1)
    at /home/user/git/qemu/exec.c:1355
#7  0x00000000600481d1 in tb_reset_jump_recursive (tb=0x7ffff4c63408)
    at /home/user/git/qemu/exec.c:1362
#8  0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c633a0, n=0)
    at /home/user/git/qemu/exec.c:1355
#9  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c633a0)
    at /home/user/git/qemu/exec.c:1361
#10 0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c63338, n=0)
    at /home/user/git/qemu/exec.c:1355
#11 0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c63338)
    at /home/user/git/qemu/exec.c:1361
#12 0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c632d0, n=0)
    at /home/user/git/qemu/exec.c:1355
---Type <return> to continue, or q <return> to quit---
#13 0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c632d0)
    at /home/user/git/qemu/exec.c:1361
#14 0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c63268, n=1)
    at /home/user/git/qemu/exec.c:1355
#15 0x00000000600481d1 in tb_reset_jump_recursive (tb=0x7ffff4c63268)
    at /home/user/git/qemu/exec.c:1362
#16 0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c63200, n=0)
    at /home/user/git/qemu/exec.c:1355
#17 0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c63200)
    at /home/user/git/qemu/exec.c:1361
#18 0x00000000600487c5 in cpu_unlink_tb (env=0x62385400) at 
/home/user/git/qemu/exec.c:1617
#19 0x00000000600488e8 in cpu_exit (env=0x62385400) at 
/home/user/git/qemu/exec.c:1662
#20 0x0000000060000798 in start_exclusive () at 
/home/user/git/qemu/linux-user/main.c:152
#21 0x0000000060000a4b in do_kernel_trap (env=0x62359940)
    at /home/user/git/qemu/linux-user/main.c:493
#22 0x00000000600023f3 in cpu_loop (env=0x62359940) at 
/home/user/git/qemu/linux-user/main.c:797
#23 0x00000000600123df in clone_func (arg=0x7ffffffd76e0)
    at /home/user/git/qemu/linux-user/syscall.c:3561
#24 0x00000000600b382d in start_thread (arg=<value optimized out>) at 
pthread_create.c:297
#25 0x00000000600f1809 in clone () at 
../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#26 0x0000000000000000 in ?? ()
(gdb) 



Its interesting to see this :
#0  0x00000000600480d4 in tb_reset_jump_recursive2 (tb=0x7ffff4c63540, n=0)
    at /home/user/git/qemu/exec.c:1333
        tb1 = 0x0                                           <<<<<<<<<<
        tb_next = 0xf4c63610                        <<<<<<<<<<
        ptb = 0x60341c91                              <<<<<<<<<<
        n1 = 0
#1  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c63540)
    at /home/user/git/qemu/exec.c:1361
No locals.
#2  0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c634d8, n=0)
    at /home/user/git/qemu/exec.c:1355
        tb1 = 0x7ffff4c634d8                          <<<<<<<<<<<
        tb_next = 0x7ffff4c63540                    <<<<<<<<<<<
        ptb = 0x7ffff4c63860                           <<<<<<<<<<<
        n1 = 0
#3  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c634d8)
    at /home/user/git/qemu/exec.c:1361
No locals.
#4  0x0000000060048160 in tb_reset_jump_recursive2 (tb=0x7ffff4c63470, n=0)
    at /home/user/git/qemu/exec.c:1355
        tb1 = 0x7ffff4c63470
        tb_next = 0x7ffff4c634d8
        ptb = 0x7ffff4c63530
        n1 = 0
#5  0x00000000600481c0 in tb_reset_jump_recursive (tb=0x7ffff4c63470)
    at /home/user/git/qemu/exec.c:1361