2.6.28.4 regression: mmap fails if mlockall used

[Sami Farin <safari-kernel@safari.iki.fi>]

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2.6.28.2 + gcc-4.3.2-7 works.
2.6.28.4 + gcc-4.4.0-0.16 does not work.
I run x86_64 SMP kernel.

# strace ./a.out ntp
12:10:14.780726 mmap(NULL, 2147624, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = -1 EFAULT (Bad address) <0.000038>
12:10:14.780809 close(3)                = 0 <0.000012>
12:10:14.780856 munmap(0x7f3476e0d000, 421232) = 0 <0.000145>
12:10:14.781054 write(2, "./a.out: getpwnam failed: Success\n"..., 34./a.out: getpwnam failed: Success
) = 34 <0.000015>

I can do malloc(3000000), then mmap call is
12:50:20.694207 mmap(NULL, 3002368, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8a8d16b000 <0.003078>

-- 
"When playing Russian roulette, the fact that the first shot
 got off safely is little comfort for the next." - Richard Feynman


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#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <pwd.h>
#include <sys/mman.h>

int main(int argc, char *argv[])
{
  struct passwd *pw;

  if (mlockall(MCL_CURRENT | MCL_FUTURE) == -1) {
    fprintf(stderr, "%s: mlockall failed: %s\n",
            argv[0], strerror(errno));
  }
  if (argc != 2) return 1;
  errno = 0;
  pw = getpwnam(argv[1]);
  if (pw == NULL) {
    fprintf(stderr, "%s: getpwnam failed: %s\n",
            argv[0], strerror(errno));
    return 1;
  }
  fprintf(stdout, "uid=%u gid=%u\n",
          (unsigned int)pw->pw_uid, (unsigned int)pw->pw_gid);
  fflush(stdout);
  return 0;
}