linux_dsm_epyc7002/Documentation/x86
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
..
i386 doc: spelling error changes 2014-05-05 15:32:05 +02:00
x86_64 Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-13 18:28:19 -07:00
00-INDEX Documentation: Fix early-microcode.txt references after file rename 2018-03-27 09:51:23 +02:00
amd-memory-encryption.txt Documentation/x86: Add AMD Secure Encrypted Virtualization (SEV) description 2017-11-07 15:35:54 +01:00
boot.txt x86/boot: Add ACPI RSDP address to setup_header 2018-10-10 10:44:22 +02:00
earlyprintk.txt x86/doc: Fix Documentation/x86/earlyprintk.txt 2018-09-10 15:09:30 +02:00
entry_64.txt x86/asm/entry/64: Update path names 2015-07-02 11:08:50 +02:00
exception-tables.txt x86/mm: Expand the exception table logic to allow new handling options 2016-02-18 09:21:46 +01:00
intel_mpx.txt x86/Documentation: Fix various typos in Documentation/x86/ files 2016-07-01 10:00:10 +02:00
intel_rdt_ui.txt x86/intel_rdt: Make CPU information accessible for pseudo-locked regions 2018-07-03 08:38:40 +02:00
kernel-stacks Documentation/x86: Rename IRQSTACKSIZE to IRQ_STACK_SIZE 2015-08-24 11:42:41 -06:00
microcode.txt firmware: Fix up docs referring to FIRMWARE_IN_KERNEL 2018-01-25 12:46:30 +01:00
mtrr.txt x86/mm/mtrr: Remove kernel internal MTRR interfaces: unexport mtrr_add() and mtrr_del() 2015-08-28 10:09:28 +02:00
orc-unwinder.txt x86/unwind: Rename unwinder config options to 'CONFIG_UNWINDER_*' 2017-10-14 10:12:12 +02:00
pat.txt x86/pat: Document the PAT initialization sequence 2016-03-29 12:23:27 +02:00
protection-keys.txt x86/pkeys: Update documentation about availability 2017-11-21 09:34:52 +01:00
pti.txt x86/pti: Document fix wrong index 2018-01-19 16:31:29 +01:00
tlb.txt x86/Documentation: Fix various typos in Documentation/x86/ files 2016-07-01 10:00:10 +02:00
topology.txt x86/topology: Fix function name in documentation 2018-02-23 08:40:12 +01:00
usb-legacy-support.txt x86: doc: move x86-generic documentation from Doc/x86/i386 2008-07-22 15:34:38 -04:00
zero-page.txt Merge branch 'linus' into WIP.x86/boot, to fix up conflicts and to pick up updates 2017-03-01 09:02:26 +01:00