$ sudo sysctl vm.mmap_rnd_bits
vm.mmap_rnd_bits = 28
$ for i in $(seq 300); do
  MSAN_OPTIONS=verbosity=1 ./python -m test test_os.test_posix -m test_fexecve 2>&1 \
    | grep -E 'execve failed|incompatible' && { echo "failed on run $i"; break; }
done
$ sudo sysctl -w vm.mmap_rnd_bits=32
vm.mmap_rnd_bits = 32
$ for i in $(seq 300); do   MSAN_OPTIONS=verbosity=1 ./python -m test test_os.test_posix -m test_fexecve 2>&1     | grep -E 'execve failed|incompatible' && { echo "$i"; break; }; done
==35706==WARNING: MemorySanitizer: memory layout is incompatible, possibly due to high-entropy ASLR.
execve failed, errno 2
4