Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
Moving TIF_32BIT to use bit 20 instead of 4 in the task flag field. This change is making room for an upcoming new task macro (_TIF_SYSCALL_EMU) which is preferred to set a bit in the lower 16-bits part of the word. This upcoming flag macro will take part in a composed macro (_TIF_SYSCALL_DOTRACE) which will contain other flags as well, and it is preferred that the whole _TIF_SYSCALL_DOTRACE macro only sets the lower 16 bits of a word, so, it could be handled using immediate operations (as load immediate, add immediate, ...) where the immediate operand (SI) is limited to 16-bits. Another possible solution would be using the LOAD_REG_IMMEDIATE() macro to load a full 64-bits word immediate, but it takes 5 operations instead of one. Having TIF_32BITS being redefined to use an upper bit is not a problem since there is only one place in the assembly code where TIF_32BIT is being used, and it could be replaced with an operation with right shift (addis), since it is used alone, i.e. not being part of a composed macro, which has different bits set, and would require LOAD_REG_IMMEDIATE(). Tested on a 64 bits Big Endian machine running a 32 bits task. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
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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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.