forked from Minki/linux
mainlining shenanigans
363524d2b1
We wish to introduce a 52-bit virtual address space for userspace but maintain compatibility with software that assumes the maximum VA space size is 48 bit. In order to achieve this, on 52-bit VA systems, we make mmap behave as if it were running on a 48-bit VA system (unless userspace explicitly requests a VA where addr[51:48] != 0). On a system running a 52-bit userspace we need TASK_SIZE to represent the 52-bit limit as it is used in various places to distinguish between kernelspace and userspace addresses. Thus we need a new limit for mmap, stack, ELF loader and EFI (which uses TTBR0) to represent the non-extended VA space. This patch introduces DEFAULT_MAP_WINDOW and DEFAULT_MAP_WINDOW_64 and switches the appropriate logic to use that instead of TASK_SIZE. Signed-off-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.