bd9e99f790
This is mandated by the current tightening of EFI executables requirements when used in a secure boot scenario. More specifically, an EFI executable cannot have a single section with RWX permissions, which conflicts with the in-place kernel decompression that is done today. Instead, the things required by the booting kernel image are done in the EFI stub now. Work by Ard Biesheuvel. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmTsMGAACgkQEsHwGGHe VUqqGg/+LJq7dapnyMiqafO9Xdpm+h7wTylChdfev7UB3wri9IJGXXFkwZZUNF8Z p2c/ECk75CG+z7ZSv+WirZLWlmlBT1D51YjI1lHmg3Vmh3YXZWJHkwaG1DI4euL7 C4gvd/gmpXGMOxjZLV/D5d7wwoO2REyVkDeCy0lqHCisvd4GRXqUJHe6hJ3GxVv/ VqbT7ZHMP4BlbWK4/yTq9+wKSC9T0OfAOW2b+K/SAh19TpRqFBpkMOxaZx0nj2Eh UxQUd2hntGtEGpPf71HPQMYCkWyvJD1LpTYfwld7tNvzXSt2xg2YZAf7WzJ0Od3b kxg2mItHhVRCcwEc9OWlphvgAYCzYECzeMniesLFeJYLMvHNtORzxNPkDLrOYjT6 0K05DEWJlEqZhIWtaKJ/SSCj7JnfmgubfK3tG3cerCelQZIvUix6ysvDBwPnqdUr 3O1d7iMlM1UtqMo0GLeIp0q1aRKMsNfRtUvqjaiQ2NjSuyJqZl8t0jfKd6DHcnuy WidBMhREULa5qYGE9dxosdTJK1wOhqomTmBSC8EeDUPevLV+DNQUn+oBOVhFvJVk gpmsr2mi9+hwC9iNh1K4wslLl9Jc/BlIY0wwC0ysh6eTWQfrvpfXrtHRpmTvwcVW g2lt+shYiPDa7q3bvqQL7iqFU6bkMGCs89EFGJEpNbBO076uNZY= =2Oej -----END PGP SIGNATURE----- Merge tag 'x86_boot_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Borislav Petkov: "Avoid the baremetal decompressor code when booting on an EFI machine. This is mandated by the current tightening of EFI executables requirements when used in a secure boot scenario. More specifically, an EFI executable cannot have a single section with RWX permissions, which conflicts with the in-place kernel decompression that is done today. Instead, the things required by the booting kernel image are done in the EFI stub now. Work by Ard Biesheuvel" * tag 'x86_boot_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/efistub: Avoid legacy decompressor when doing EFI boot x86/efistub: Perform SNP feature test while running in the firmware efi/libstub: Add limit argument to efi_random_alloc() x86/decompressor: Factor out kernel decompression and relocation x86/decompressor: Move global symbol references to C code decompress: Use 8 byte alignment x86/efistub: Prefer EFI memory attributes protocol over DXE services x86/efistub: Perform 4/5 level paging switch from the stub x86/decompressor: Merge trampoline cleanup with switching code x86/decompressor: Pass pgtable address to trampoline directly x86/decompressor: Only call the trampoline when changing paging levels x86/decompressor: Call trampoline directly from C code x86/decompressor: Avoid the need for a stack in the 32-bit trampoline x86/decompressor: Use standard calling convention for trampoline x86/decompressor: Call trampoline as a normal function x86/decompressor: Assign paging related global variables earlier x86/decompressor: Store boot_params pointer in callee save register x86/efistub: Clear BSS in EFI handover protocol entrypoint x86/decompressor: Avoid magic offsets for EFI handover entrypoint x86/efistub: Simplify and clean up handover entry code ...
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.