mainlining shenanigans
a9c5ad31fb
In C, struct value can be passed as a function argument. For small structs, struct value may be passed in one or more registers. For trampoline based bpf programs, this would cause complication since one-to-one mapping between function argument and arch argument register is not valid any more. The latest llvm16 added bpf support to pass by values for struct up to 16 bytes ([1]). This is also true for x86_64 architecture where two registers will hold the struct value if the struct size is >8 and <= 16. This may not be true if one of struct member is 'double' type but in current linux source code we don't have such instance yet, so we assume all >8 && <= 16 struct holds two general purpose argument registers. Also change on-stack nr_args value to the number of registers holding the arguments. This will permit bpf_get_func_arg() helper to get all argument values. [1] https://reviews.llvm.org/D132144 Signed-off-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20220831152652.2078600-1-yhs@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| 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.