linux/arch/x86/boot
Juergen Gross ae7e1238e6 x86/boot: Add ACPI RSDP address to setup_header
Xen PVH guests receive the address of the RSDP table from Xen. In order
to support booting a Xen PVH guest via Grub2 using the standard x86
boot entry we need a way for Grub2 to pass the RSDP address to the
kernel.

For this purpose expand the struct setup_header to hold the physical
address of the RSDP address. Being zero means it isn't specified and
has to be located the legacy way (searching through low memory or
EBDA).

While documenting the new setup_header layout and protocol version
2.14 add the missing documentation of protocol version 2.13.

There are Grub2 versions in several distros with a downstream patch
violating the boot protocol by writing past the end of setup_header.
This requires another update of the boot protocol to enable the kernel
to distinguish between a specified RSDP address and one filled with
garbage by such a broken Grub2.

From protocol 2.14 on Grub2 will write the version it is supporting
(but never a higher value than found to be supported by the kernel)
ored with 0x8000 to the version field of setup_header. This enables
the kernel to know up to which field Grub2 has written information
to. All fields after that are supposed to be clobbered.

Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boris.ostrovsky@oracle.com
Cc: bp@alien8.de
Cc: corbet@lwn.net
Cc: linux-doc@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181010061456.22238-3-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-10 10:44:22 +02:00
..
compressed x86/boot: Fix kexec booting failure in the SEV bit detection code 2018-09-27 19:35:03 +02:00
tools License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
.gitignore x86/build: Add more generated files to the .gitignore file 2017-11-07 11:22:21 +01:00
a20.c
apm.c
bioscall.S
bitops.h x86/boot: Use CC_SET()/CC_OUT() instead of open coding it 2018-08-02 14:30:42 +02:00
boot.h x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup 2017-04-20 10:05:23 +02:00
cmdline.c
code16gcc.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
copy.S x86/boot: Remove unused copy_*_gs() functions 2017-06-05 09:35:16 +02:00
cpu.c Revert "x86/boot: Fail the boot if !M486 and CPUID is missing" 2016-12-19 11:54:20 +01:00
cpucheck.c x86/boot: Detect 5-level paging support 2017-04-04 08:22:33 +02:00
cpuflags.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cpuflags.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ctype.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
early_serial_console.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
edd.c
genimage.sh x86/build: Make isoimage work on Debian 2017-12-16 16:23:31 +01:00
header.S x86/boot: Add ACPI RSDP address to setup_header 2018-10-10 10:44:22 +02:00
install.sh
main.c x86/boot: Obsolete the MCA sys_desc_table 2015-07-21 10:55:11 +02:00
Makefile x86/build: Factor out fdimage/isoimage generation commands to standalone script 2017-11-07 11:22:20 +01:00
memory.c x86/boot/e820: Separate the E820 ABI structures from the in-kernel structures 2017-01-29 13:39:32 +01:00
mkcpustr.c x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
mtools.conf.in
pm.c
pmjump.S
printf.c
regs.c
setup.ld
string.c x86/boot: Use CC_SET()/CC_OUT() instead of open coding it 2018-08-02 14:30:42 +02:00
string.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tty.c
version.c
vesa.h
video-bios.c
video-mode.c x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
video-vesa.c
video-vga.c x86: Use ARRAY_SIZE 2017-10-19 16:15:47 +02:00
video.c x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
video.h x86/boot/video: Move the 'video_segment' variable to video.c 2015-02-19 00:25:05 +01:00