blob: 662b73971a67b22eddf99b5b975da893b72a0b40 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
|
<previous description obsolete, deleted>
Virtual memory map with 4 level page tables:
0000000000000000 - 00007fffffffffff (=47bits) user space, different per mm
hole caused by [48:63] sign extension
ffff800000000000 - ffff80ffffffffff (=40bits) guard hole
ffff810000000000 - ffffc0ffffffffff (=46bits) direct mapping of phys. memory
ffffc10000000000 - ffffc1ffffffffff (=40bits) hole
ffffc20000000000 - ffffe1ffffffffff (=45bits) vmalloc/ioremap space
... unused hole ...
ffffffff80000000 - ffffffff82800000 (=40MB) kernel text mapping, from phys 0
... unused hole ...
ffffffff88000000 - fffffffffff00000 (=1919MB) module mapping space
vmalloc space is lazily synchronized into the different PML4 pages of
the processes using the page fault handler, with init_level4_pgt as
reference.
Current X86-64 implementations only support 40 bit of address space,
but we support upto 46bits. This expands into MBZ space in the page tables.
-Andi Kleen, Jul 2004
|
