MEM_RESERVE The function reserves a range of the process's virtual address space without allocating any actual physical storage in memory or in the paging file on disk. Other memory allocation functions, such as malloc and LocalAlloc, cannot use a reserved range of memory until it is released. You can commit reserved memory pages in subsequent calls to the VirtualAllocEx function.

seems we have to do 2 virtualalloc's
one with reserve one with commit at least i understand it that way