Otherwise a test can create or delete some mappings:

8306  getppid()                         = 83
8306  kill(83, SIGTERM)                 = 0
8306  clock_gettime(CLOCK_BOOTTIME, {1916694, 423447417}) = 0
8306  clock_gettime(CLOCK_MONOTONIC_COARSE, {1916694, 419509587}) = 0
8306  open("/etc/localtime", O_RDONLY|O_CLOEXEC)              = 3
8306  fstat(3, {st_mode=S_IFREG|0644, st_size=127, ...}) = 0
8306  fstat(3, {st_mode=S_IFREG|0644, st_size=127, ...}) = 0
8306  mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0 <unfinished ...>
8306  <... mmap resumed> )              = 0x3fffa8570000
8306  read(3, "TZif2...", 4096) = 127
8306  lseek(3, -71, SEEK_CUR)             = 56
8306  read(3, "TZif2...", 4096) = 71
8306  close(3 <unfinished ...>
8306  <... close resumed> )             = 0
8306  munmap(0x3fffa8570000, 4096 <unfinished ...>
8306  <... munmap resumed> )            = 0
8306  write(2, "12:15:36.347:    84: ( start) boottime 1916694 boottime-coarse 1916694 total_sleep_time 0\n", 90 )             = 90
8306  futex(0x10020850, FUTEX_WAIT, 0, NULL <unfinished ...>

Reported-by: Mr Jenkins
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>