diff options
Diffstat (limited to 'Documentation/arm64/memory.txt')
-rw-r--r-- | Documentation/arm64/memory.txt | 44 |
1 files changed, 40 insertions, 4 deletions
diff --git a/Documentation/arm64/memory.txt b/Documentation/arm64/memory.txt index 5f583af0a6e1..d50fa618371b 100644 --- a/Documentation/arm64/memory.txt +++ b/Documentation/arm64/memory.txt @@ -21,7 +21,7 @@ The swapper_pgd_dir address is written to TTBR1 and never written to TTBR0. -AArch64 Linux memory layout: +AArch64 Linux memory layout with 4KB pages: Start End Size Use ----------------------------------------------------------------------- @@ -35,17 +35,46 @@ ffffffbc00000000 ffffffbdffffffff 8GB vmemmap ffffffbe00000000 ffffffbffbbfffff ~8GB [guard, future vmmemap] -ffffffbffbc00000 ffffffbffbdfffff 2MB earlyprintk device +ffffffbffa000000 ffffffbffaffffff 16MB PCI I/O space -ffffffbffbe00000 ffffffbffbe0ffff 64KB PCI I/O space +ffffffbffb000000 ffffffbffbbfffff 12MB [guard] -ffffffbbffff0000 ffffffbcffffffff ~2MB [guard] +ffffffbffbc00000 ffffffbffbdfffff 2MB fixed mappings + +ffffffbffbe00000 ffffffbffbffffff 2MB [guard] ffffffbffc000000 ffffffbfffffffff 64MB modules ffffffc000000000 ffffffffffffffff 256GB kernel logical memory map +AArch64 Linux memory layout with 64KB pages: + +Start End Size Use +----------------------------------------------------------------------- +0000000000000000 000003ffffffffff 4TB user + +fffffc0000000000 fffffdfbfffeffff ~2TB vmalloc + +fffffdfbffff0000 fffffdfbffffffff 64KB [guard page] + +fffffdfc00000000 fffffdfdffffffff 8GB vmemmap + +fffffdfe00000000 fffffdfffbbfffff ~8GB [guard, future vmmemap] + +fffffdfffa000000 fffffdfffaffffff 16MB PCI I/O space + +fffffdfffb000000 fffffdfffbbfffff 12MB [guard] + +fffffdfffbc00000 fffffdfffbdfffff 2MB fixed mappings + +fffffdfffbe00000 fffffdfffbffffff 2MB [guard] + +fffffdfffc000000 fffffdffffffffff 64MB modules + +fffffe0000000000 ffffffffffffffff 2TB kernel logical memory map + + Translation table lookup with 4KB pages: +--------+--------+--------+--------+--------+--------+--------+--------+ @@ -73,3 +102,10 @@ Translation table lookup with 64KB pages: | | +--------------------------> [41:29] L2 index (only 38:29 used) | +-------------------------------> [47:42] L1 index (not used) +-------------------------------------------------> [63] TTBR0/1 + +When using KVM, the hypervisor maps kernel pages in EL2, at a fixed +offset from the kernel VA (top 24bits of the kernel VA set to zero): + +Start End Size Use +----------------------------------------------------------------------- +0000004000000000 0000007fffffffff 256GB kernel objects mapped in HYP |