static unsigned long last_ram_page(void)
{
    RAMBlock *block;
    ram_addr_t last = 0;

    RCU_READ_LOCK_GUARD();
    RAMBLOCK_FOREACH(block) {
        last = MAX(last, block->offset + block->max_length);
    }
    return last >> TARGET_PAGE_BITS;
}
static unsigned long last_ram_page(void)
{
    RAMBlock *block;
    ram_addr_t last = 0;

    RCU_READ_LOCK_GUARD();
    RAMBLOCK_FOREACH(block) {
        last = MAX(last, block->offset + block->max_length);
    }
    return last >> TARGET_PAGE_BITS;
}