x86/x86_64/mm.rst

7 Complete virtual memory map with 4-level page tables
32 …0000000000000000 |    0       | 00007fffffffffff |  128 TB | user-space virtual memory, different …
36 …         |            |                  |         |     virtual memory addresses up to the -128 TB
40 …                                       | Kernel-space virtual memory, shared between all processes:
45 … -119.5  TB | ffffc87fffffffff |   64 TB | direct mapping of all physical memory (page_offset_base)
49    ffffea0000000000 |  -22    TB | ffffeaffffffffff |    1 TB | virtual memory map (vmemmap_base)
51    ffffec0000000000 |  -20    TB | fffffbffffffffff |   16 TB | KASAN shadow memory
75 Complete virtual memory map with 5-level page tables
80  - With 56-bit addresses, user-space memory gets expanded by a factor of 512x,
83    memory supported.
91 …0000000000000000 |    0       | 00ffffffffffffff |   64 PB | user-space virtual memory, different …
95 …          |            |                  |         |     virtual memory addresses up to the -64 PB
99 …                                       | Kernel-space virtual memory, shared between all processes:
104 …  -59.75 PB | ff90ffffffffffff |   32 PB | direct mapping of all physical memory (page_offset_base)
108    ffd4000000000000 |  -11    PB | ffd5ffffffffffff |  0.5 PB | virtual memory map (vmemmap_base)
110    ffdf000000000000 |   -8.25 PB | fffffbffffffffff |   ~8 PB | KASAN shadow memory
139 The direct mapping covers all memory in the system up to the highest
140 memory address (this means in some cases it can also include PCI memory
144 memory window (this size is arbitrary, it can be raised later if needed).
149 physical memory, vmalloc/ioremap space and virtual memory map are randomized.