e05d4cd9b8
RELR as a relocation packing format for relative relocations for reducing the size of relative relocation records. In a position independent executable there are often many relative relocation records, and our vmlinux is a PIE. The LLD linker (since 17.0.0) and the BFD linker (since 2.43) supports packing the relocations in the RELR format for LoongArch, with the flag -z pack-relative-relocs. Commits5cf896fb6b("arm64: Add support for relocating the kernel with RELR relocations") andccb2d173b9("Makefile: use -z pack-relative-relocs") have already added the framework to use RELR. We just need to wire it up and process the RELR relocation records in relocate_relative() in addition to the RELA relocation records. A ".p2align 3" directive is added to la_abs macro or the BFD linker cannot pack the relocation records against the .la_abs section (the ". = ALIGN(8);" directive in vmlinux.lds.S is too late in the linking process). With defconfig and CONFIG_RELR vmlinux.efi is 2.1 MiB (6%) smaller, and vmlinuz.efi (using gzip compression) is 384 KiB (2.8%) smaller. Link: https://groups.google.com/d/topic/generic-abi/bX460iggiKg Link: https://reviews.llvm.org/D138135#4531389 Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d89ecf33ab6d Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
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 reStructuredText 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.