diff options
| author | Stuart Menefy <stuart.menefy@codasip.com> | 2024-06-30 12:05:49 +0100 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-07-26 05:50:50 -0700 |
| commit | 5c8405d763dc2b125b39166bc70be1b8dcc80582 (patch) | |
| tree | 95eb880448a9857ddc7a599428faa013e53caf1b /Documentation/arch | |
| parent | 3aa1a7d013dd69d187a7b2daa1a0961b7d4edc71 (diff) | |
riscv: Extend sv39 linear mapping max size to 128G
This harmonizes all virtual addressing modes which can now all map
(PGDIR_SIZE * PTRS_PER_PGD) / 4 of physical memory.
The RISCV implementation of KASAN requires that the boundary between
shallow mappings are aligned on an 8G boundary. In this case we need
VMALLOC_START to be 8G aligned. So although we only need to move the
start of the linear mapping down by 4GiB to allow 128GiB to be mapped,
we actually move it down by 8GiB (creating a 4GiB hole between the
linear mapping and KASAN shadow space) to maintain the alignment
requirement.
Signed-off-by: Stuart Menefy <stuart.menefy@codasip.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240630110550.1731929-1-stuart.menefy@codasip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'Documentation/arch')
| -rw-r--r-- | Documentation/arch/riscv/vm-layout.rst | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/Documentation/arch/riscv/vm-layout.rst b/Documentation/arch/riscv/vm-layout.rst index e476b4386bd9..077b968dcc81 100644 --- a/Documentation/arch/riscv/vm-layout.rst +++ b/Documentation/arch/riscv/vm-layout.rst @@ -47,11 +47,12 @@ RISC-V Linux Kernel SV39 | Kernel-space virtual memory, shared between all processes: ____________________________________________________________|___________________________________________________________ | | | | - ffffffc6fea00000 | -228 GB | ffffffc6feffffff | 6 MB | fixmap - ffffffc6ff000000 | -228 GB | ffffffc6ffffffff | 16 MB | PCI io - ffffffc700000000 | -228 GB | ffffffc7ffffffff | 4 GB | vmemmap - ffffffc800000000 | -224 GB | ffffffd7ffffffff | 64 GB | vmalloc/ioremap space - ffffffd800000000 | -160 GB | fffffff6ffffffff | 124 GB | direct mapping of all physical memory + ffffffc4fea00000 | -236 GB | ffffffc4feffffff | 6 MB | fixmap + ffffffc4ff000000 | -236 GB | ffffffc4ffffffff | 16 MB | PCI io + ffffffc500000000 | -236 GB | ffffffc5ffffffff | 4 GB | vmemmap + ffffffc600000000 | -232 GB | ffffffd5ffffffff | 64 GB | vmalloc/ioremap space + ffffffd600000000 | -168 GB | fffffff5ffffffff | 128 GB | direct mapping of all physical memory + | | | | fffffff700000000 | -36 GB | fffffffeffffffff | 32 GB | kasan __________________|____________|__________________|_________|____________________________________________________________ | |