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Subject2.6.28.4 regression: mmap fails if mlockall used
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

#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;
}

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