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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-08-07 13:11:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-08-07 13:11:27 +0000
commit34996e42f82bfd60bc2c191e5cae3c6ab233ec6c (patch)
tree62db60558cbf089714b48daeabca82bf2b20b20e /Documentation/arch/riscv
parentAdding debian version 6.8.12-1. (diff)
downloadlinux-34996e42f82bfd60bc2c191e5cae3c6ab233ec6c.tar.xz
linux-34996e42f82bfd60bc2c191e5cae3c6ab233ec6c.zip
Merging upstream version 6.9.7.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/arch/riscv')
-rw-r--r--Documentation/arch/riscv/vm-layout.rst16
1 files changed, 5 insertions, 11 deletions
diff --git a/Documentation/arch/riscv/vm-layout.rst b/Documentation/arch/riscv/vm-layout.rst
index 69ff6da1db..e476b4386b 100644
--- a/Documentation/arch/riscv/vm-layout.rst
+++ b/Documentation/arch/riscv/vm-layout.rst
@@ -144,14 +144,8 @@ passing 0 into the hint address parameter of mmap. On CPUs with an address space
smaller than sv48, the CPU maximum supported address space will be the default.
Software can "opt-in" to receiving VAs from another VA space by providing
-a hint address to mmap. A hint address passed to mmap will cause the largest
-address space that fits entirely into the hint to be used, unless there is no
-space left in the address space. If there is no space available in the requested
-address space, an address in the next smallest available address space will be
-returned.
-
-For example, in order to obtain 48-bit VA space, a hint address greater than
-:code:`1 << 47` must be provided. Note that this is 47 due to sv48 userspace
-ending at :code:`1 << 47` and the addresses beyond this are reserved for the
-kernel. Similarly, to obtain 57-bit VA space addresses, a hint address greater
-than or equal to :code:`1 << 56` must be provided.
+a hint address to mmap. When a hint address is passed to mmap, the returned
+address will never use more bits than the hint address. For example, if a hint
+address of `1 << 40` is passed to mmap, a valid returned address will never use
+bits 41 through 63. If no mappable addresses are available in that range, mmap
+will return `MAP_FAILED`.