diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-14 13:43:24 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-14 13:43:24 -0700 |
| commit | a3da5bf84a97d48cfaf66c6842470fc403da5121 (patch) | |
| tree | cdf66c0cff8c61eedd60601fc9dffdd1ed39b880 /Documentation/x86/x86_64/mm.txt | |
| parent | 3b23e665b68387f5ee7b21f7b75ceea4d9acae4a (diff) | |
| parent | d59fdcf2ac501de99c3dfb452af5e254d4342886 (diff) | |
Merge branch 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (821 commits)
x86: make 64bit hpet_set_mapping to use ioremap too, v2
x86: get x86_phys_bits early
x86: max_low_pfn_mapped fix #4
x86: change _node_to_cpumask_ptr to return const ptr
x86: I/O APIC: remove an IRQ2-mask hack
x86: fix numaq_tsc_disable calling
x86, e820: remove end_user_pfn
x86: max_low_pfn_mapped fix, #3
x86: max_low_pfn_mapped fix, #2
x86: max_low_pfn_mapped fix, #1
x86_64: fix delayed signals
x86: remove conflicting nx6325 and nx6125 quirks
x86: Recover timer_ack lost in the merge of the NMI watchdog
x86: I/O APIC: Never configure IRQ2
x86: L-APIC: Always fully configure IRQ0
x86: L-APIC: Set IRQ0 as edge-triggered
x86: merge dwarf2 headers
x86: use AS_CFI instead of UNWIND_INFO
x86: use ignore macro instead of hash comment
x86: use matching CFI_ENDPROC
...
Diffstat (limited to 'Documentation/x86/x86_64/mm.txt')
| -rw-r--r-- | Documentation/x86/x86_64/mm.txt | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt new file mode 100644 index 00000000000..efce7509736 --- /dev/null +++ b/Documentation/x86/x86_64/mm.txt @@ -0,0 +1,28 @@ + +<previous description obsolete, deleted> + +Virtual memory map with 4 level page tables: + +0000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm +hole caused by [48:63] sign extension +ffff800000000000 - ffff80ffffffffff (=40 bits) guard hole +ffff810000000000 - ffffc0ffffffffff (=46 bits) direct mapping of all phys. memory +ffffc10000000000 - ffffc1ffffffffff (=40 bits) hole +ffffc20000000000 - ffffe1ffffffffff (=45 bits) vmalloc/ioremap space +ffffe20000000000 - ffffe2ffffffffff (=40 bits) virtual memory map (1TB) +... unused hole ... +ffffffff80000000 - ffffffffa0000000 (=512 MB) kernel text mapping, from phys 0 +ffffffffa0000000 - fffffffffff00000 (=1536 MB) module mapping space + +The direct mapping covers all memory in the system up to 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. + +Current X86-64 implementations only support 40 bits of address space, +but we support up to 46 bits. This expands into MBZ space in the page tables. + +-Andi Kleen, Jul 2004 |