kernel/git/stable/linux.git/Documentation/x86/boot.rst, branch master

docs: move x86 documentation into Documentation/arch/

2023-03-30T18:58:51+00:00

Move the x86 documentation under Documentation/arch/ as a way of cleaning up the top-level directory and making the structure of our docs more closely match the structure of the source directories it describes. All in-kernel references to the old paths have been updated. Acked-by: Dave Hansen Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org Cc: Borislav Petkov Cc: Thomas Gleixner Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/ Signed-off-by: Jonathan Corbet

Documentation/x86/boot: Reserve type_of_loader=13 for barebox

2022-10-17T09:22:33+00:00

barebox[1], a bootloader for mostly ARM and MIPS embedded systems, can also be built as EFI payload for x86[2] to provide redundant power-fail safe, watchdog-supervised boot up. Since its v2015.09.0 release, it has been booting Linux on x86 with type_of_loader=0xff[3]. Reserve 13, the next free id, so that can be used instead in the future. [1]: https://www.barebox.org/ [2]: https://www.barebox.org/doc/latest/boards/efi.html [3]: https://elixir.bootlin.com/barebox/v2022.09.0/source/common/efi/payload/image.c#L217 Signed-off-by: Ahmad Fatoum Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20221002125752.3400831-1-a.fatoum@pengutronix.de

docs: x86: avoid using ReST :doc:`foo` markup

2021-06-17T19:24:39+00:00

The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Acked-by: Peter Zijlstra (Intel) Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/17c68b5f1d72488431c77c1de9f13683fe9f536c.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

Documentation/x86/boot.rst: Correct the example of SETUP_INDIRECT

2021-01-28T22:25:31+00:00

struct setup_data.len is the length of data field. In case of SETUP_INDIRECT, it should be sizeof(setup_indirect). Signed-off-by: Cao jin Reviewed-by: Daniel Kiper Link: https://lore.kernel.org/r/20210127084911.63438-1-jojing64@gmail.com Signed-off-by: Jonathan Corbet

Documentation/x86: Fix incorrect references to zero-page.txt

2020-10-02T20:49:29+00:00

The file zero-page.txt does not exit. Add links to zero-page.rst instead. [ bp: Massage a bit. ] Signed-off-by: Heinrich Schuchardt Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20201002190623.7489-1-xypron.glpk@gmx.de

x86: Add support for ZSTD compressed kernel

2020-07-31T09:49:09+00:00

- Add support for zstd compressed kernel - Define __DISABLE_EXPORTS in Makefile - Remove __DISABLE_EXPORTS definition from kaslr.c - Bump the heap size for zstd. - Update the documentation. Integrates the ZSTD decompression code to the x86 pre-boot code. Zstandard requires slightly more memory during the kernel decompression on x86 (192 KB vs 64 KB), and the memory usage is independent of the window size. __DISABLE_EXPORTS is now defined in the Makefile, which covers both the existing use in kaslr.c, and the use needed by the zstd decompressor in misc.c. This patch has been boot tested with both a zstd and gzip compressed kernel on i386 and x86_64 using buildroot and QEMU. Additionally, this has been tested in production on x86_64 devices. We saw a 2 second boot time reduction by switching kernel compression from xz to zstd. Signed-off-by: Nick Terrell Signed-off-by: Ingo Molnar Tested-by: Sedat Dilek Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20200730190841.2071656-7-nickrterrell@gmail.com

Documentation/x86, efi/x86: Clarify EFI handover protocol and its requirements

2020-04-14T06:32:15+00:00

The EFI handover protocol was introduced on x86 to permit the boot loader to pass a populated boot_params structure as an additional function argument to the entry point. This allows the bootloader to pass the base and size of a initrd image, which is more flexible than relying on the EFI stub's file I/O routines, which can only access the file system from which the kernel image itself was loaded from firmware. This approach requires a fair amount of internal knowledge regarding the layout of the boot_params structure on the part of the boot loader, as well as knowledge regarding the allowed placement of the initrd in memory, and so it has been deprecated in favour of a new initrd loading method that is based on existing UEFI protocols and best practices. So update the x86 boot protocol documentation to clarify that the EFI handover protocol has been deprecated, and while at it, add a note that invoking the EFI handover protocol still requires the PE/COFF image to be loaded properly (as opposed to simply being copied into memory). Also, drop the code32_start header field from the list of values that need to be provided, as this is no longer required. Reviewed-by: Borislav Petkov Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200409130434.6736-7-ardb@kernel.org

x86/boot: Remove KEEP_SEGMENTS support

2020-02-22T22:37:37+00:00

Commit a24e785111a3 ("i386: paravirt boot sequence") added this flag for use by paravirtualized environments such as Xen. However, Xen never made use of this flag [1], and it was only ever used by lguest [2]. Commit ecda85e70277 ("x86/lguest: Remove lguest support") removed lguest, so KEEP_SEGMENTS has lost its last user. [1] https://lore.kernel.org/lkml/4D4B097C.5050405@goop.org [2] https://www.mail-archive.com/lguest@lists.ozlabs.org/msg00469.html Signed-off-by: Arvind Sankar Link: https://lore.kernel.org/r/20200202171353.3736319-2-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel

Merge tag 'docs-5.6' of git://git.lwn.net/linux

2020-01-29T23:27:31+00:00

Pull documentation updates from Jonathan Corbet: "It has been a relatively quiet cycle for documentation, but there's still a couple of things of note: - Conversion of the NFS documentation to RST - A new document on how to help with documentation (and a maintainer profile entry too) Plus the usual collection of typo fixes, etc" * tag 'docs-5.6' of git://git.lwn.net/linux: (40 commits) docs: filesystems: add overlayfs to index.rst docs: usb: remove some broken references scripts/find-unused-docs: Fix massive false positives docs: nvdimm: use ReST notation for subsection zram: correct documentation about sysfs node of huge page writeback Documentation: zram: various fixes in zram.rst Add a maintainer entry profile for documentation Add a document on how to contribute to the documentation docs: Keep up with the location of NoUri Documentation: Call out example SYM_FUNC_* usage as x86-specific Documentation: nfs: fault_injection: convert to ReST Documentation: nfs: pnfs-scsi-server: convert to ReST Documentation: nfs: convert pnfs-block-server to ReST Documentation: nfs: idmapper: convert to ReST Documentation: convert nfsd-admin-interfaces to ReST Documentation: nfs-rdma: convert to ReST Documentation: nfsroot.rst: COSMETIC: refill a paragraph Documentation: nfsroot.txt: convert to ReST Documentation: convert nfs.txt to ReST Documentation: filesystems: convert vfat.txt to RST ...

Documentation: boot.rst: fix warnings

2020-01-10T17:54:46+00:00

Fix WARNING: Inline emphasis start-string without end-string. This warning was due to wrong syntax being used. Signed-off-by: Daniel W. S. Almeida Link: https://lore.kernel.org/r/20191223033121.1584930-1-dwlsalmeida@gmail.com Signed-off-by: Jonathan Corbet