[RFC] does ioremap() cause memory leak?

[Xishi Qiu]

When we use iounmap() to free the mapping, it calls unmap_vmap_area() to clear page table,
but do not free the memory of page table, right?

So when use ioremap() to mapping another area(incluce the area before), it may use
large mapping(e.g. ioremap_pmd_enabled()), so the original page table memory(e.g. pte memory)
will be lost, it cause memory leak, right?

Thanks,
Xishi Qiu