Hi Björn,
On 11/18/22 18:15, Björn Töpel wrote:
From: Björn Töpel <bjorn@xxxxxxxxxxxx>
RISC-V has been supporting the "sv57" address translation mode for a
while, but is has not been added to the VM layout documentation. Let
us fix that.
Signed-off-by: Björn Töpel <bjorn@xxxxxxxxxxxx>
---
v2: * Cosmestics (Alex)
* Corrected kasan address (Alex)
---
Documentation/riscv/vm-layout.rst | 36 +++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/Documentation/riscv/vm-layout.rst b/Documentation/riscv/vm-layout.rst
index 5b36e45fef60..3be44e74ec5d 100644
--- a/Documentation/riscv/vm-layout.rst
+++ b/Documentation/riscv/vm-layout.rst
@@ -97,3 +97,39 @@ RISC-V Linux Kernel SV48
ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | modules, BPF
ffffffff80000000 | -2 GB | ffffffffffffffff | 2 GB | kernel
__________________|____________|__________________|_________|____________________________________________________________
+
+
+RISC-V Linux Kernel SV57
+------------------------
+
+::
+
+ ========================================================================================================================
+ Start addr | Offset | End addr | Size | VM area description
+ ========================================================================================================================
+ | | | |
+ 0000000000000000 | 0 | 00ffffffffffffff | 64 PB | user-space virtual memory, different per mm
+ __________________|____________|__________________|_________|___________________________________________________________
+ | | | |
+ 0100000000000000 | +64 PB | feffffffffffffff | ~16K PB | ... huge, almost 64 bits wide hole of non-canonical
+ | | | | virtual memory addresses up to the -64 PB
+ | | | | starting offset of kernel mappings.
+ __________________|____________|__________________|_________|___________________________________________________________
+ |
+ | Kernel-space virtual memory, shared between all processes:
+ ____________________________________________________________|___________________________________________________________
+ | | | |
+ ff1bfffffee00000 | -57 PB | ff1bfffffeffffff | 2 MB | fixmap
+ ff1bffffff000000 | -57 PB | ff1bffffffffffff | 16 MB | PCI io
+ ff1c000000000000 | -57 PB | ff1fffffffffffff | 1 PB | vmemmap
+ ff20000000000000 | -56 PB | ff5fffffffffffff | 16 PB | vmalloc/ioremap space
+ ff60000000000000 | -40 PB | ffdeffffffffffff | 32 PB | direct mapping of all physical memory
+ ffdf000000000000 | -8 PB | fffffffeffffffff | 8 PB | kasan
+ __________________|____________|__________________|_________|____________________________________________________________
+ |
+ | Identical layout to the 39-bit one from here on:
+ ____________________________________________________________|____________________________________________________________
+ | | | |
+ ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | modules, BPF
+ ffffffff80000000 | -2 GB | ffffffffffffffff | 2 GB | kernel
+ __________________|____________|__________________|_________|____________________________________________________________
Thanks for the corrections, this looks great to me now, you can add:
Reviewed-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>
Thanks,
Alex
