The region of affected pages includes all pages containing one or more bytes in the range from the lpAddress parameter to (lpAddress+dwSize). This means that a 2-byte range straddling a page boundary causes the protection attributes of both pages to be changed.
某个页面只要有一个字节在lpAddress到lpAddress+dwSize范围内,这个页面就会受到影响,不过The pages cannot span adjacent reserved regions that were allocated by separate calls to VirtualAlloc or VirtualAllocEx using MEM_RESERVE.不能跨过两次分配的不同的内存区域。