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Charlie Jenkins <charlie@rivosinc.com> says: A handful of module relocations were missing, this patch includes the remaining ones. I also wrote some test cases to ensure that module loading works properly. Some relocations cannot be supported in the kernel, these include the ones that rely on thread local storage and dynamic linking. This patch also overhauls the implementation of ADD/SUB/SET/ULEB128 relocations to handle overflow. "Overflow" is different for ULEB128 since it is a variable-length encoding that the compiler can be expected to generate enough space for. Instead of overflowing, ULEB128 will expand into the next 8-bit segment of the location. A psABI proposal [1] was merged that mandates that SET_ULEB128 and SUB_ULEB128 are paired, however the discussion following the merging of the pull request revealed that while the pull request was valid, it would be better for linkers to properly handle this overflow. This patch proactively implements this methodology for future compatibility. This can be tested by enabling KUNIT, RUNTIME_KERNEL_TESTING_MENU, and RISCV_MODULE_LINKING_KUNIT. [1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/403 * b4-shazam-merge: riscv: Add tests for riscv module loading riscv: Add remaining module relocations riscv: Avoid unaligned access when relocating modules Link: https://lore.kernel.org/r/20231101-module_relocations-v9-0-8dfa3483c400@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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.