Mastering Assembly Programming

Long mode - paging

The only address virtualization allowed in long mode is paging with PAE enabled; however, it adds one more table--the page map level 4 table as the root entry; therefore, the conversion of a virtual address to a physical address uses the bits of a virtual address in the way described in the following table:

Address bits	Meaning
0 - 11	Offset into a 4 KB page
12 - 20	Index of a page entry in the table of 512 pages
21 - 29	Index of a page table entry in the page directory
30 - 38	Index of a page directory entry in the page directory pointer table
39 - 47	Index of a page directory pointer table in the page-map level 4 table

Table 6: Virtual to physical address translation in long mode

It is, however, important ...