X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=Documentation%2Fx86_64%2Fmm.txt;h=133561b9cb0c32f03f840af433bdd4976f68a3c0;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=662b73971a67b22eddf99b5b975da893b72a0b40;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git diff --git a/Documentation/x86_64/mm.txt b/Documentation/x86_64/mm.txt index 662b73971..133561b9c 100644 --- a/Documentation/x86_64/mm.txt +++ b/Documentation/x86_64/mm.txt @@ -6,7 +6,7 @@ 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 +ffff810000000000 - ffffc0ffffffffff (=46bits) direct mapping of all phys. memory ffffc10000000000 - ffffc1ffffffffff (=40bits) hole ffffc20000000000 - ffffe1ffffffffff (=45bits) vmalloc/ioremap space ... unused hole ... @@ -14,6 +14,10 @@ ffffffff80000000 - ffffffff82800000 (=40MB) kernel text mapping, from phys 0 ... unused hole ... ffffffff88000000 - fffffffffff00000 (=1919MB) module mapping space +The direct mapping covers all memory in the system upto the highest +memory address (this means in some cases it can also include PCI memory +holes) + vmalloc space is lazily synchronized into the different PML4 pages of the processes using the page fault handler, with init_level4_pgt as reference.