[PATCH v5 2/3] x86/boot: Introduce the kernel_info.setup_type_max

Daniel Kiper
2019-11-04T15:16:33Z

This field contains maximal allowed type for setup_data.

This patch does not bump setup_header version in arch/x86/boot/header.S
because it will be followed by additional changes coming into the
Linux/x86 boot protocol.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
---
v5 - suggestions/fixes:
- move incorrect references to the setup_indirect to the
patch introducing it,
- do not bump setup_header version in arch/x86/boot/header.S
(suggested by H. Peter Anvin).
---
Documentation/x86/boot.rst | 9 ++++++++-
arch/x86/boot/compressed/kernel_info.S | 5 +++++
arch/x86/include/uapi/asm/bootparam.h | 3 +++
3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/Documentation/x86/boot.rst b/Documentation/x86/boot.rst
index c60fafda9427..1dad6eee8a5c 100644
--- a/Documentation/x86/boot.rst
+++ b/Documentation/x86/boot.rst
@@ -73,7 +73,7 @@ Protocol 2.14: BURNT BY INCORRECT COMMIT ae7e1238e68f2a472a125673ab506d49158c188
(x86/boot: Add ACPI RSDP address to setup_header)
DO NOT USE!!! ASSUME SAME AS 2.13.

-Protocol 2.15: (Kernel 5.5) Added the kernel_info.
+Protocol 2.15: (Kernel 5.5) Added the kernel_info and kernel_info.setup_type_max.
============= ============================================================

.. note::
@@ -981,6 +981,13 @@ Offset/size: 0x0008/4
This field contains the size of the kernel_info including kernel_info.header
and kernel_info.kernel_info_var_len_data.

+============ ==============
+Field name: setup_type_max
+Offset/size: 0x0008/4
+============ ==============
+
+ This field contains maximal allowed type for setup_data.
+

The Image Checksum
==================
diff --git a/arch/x86/boot/compressed/kernel_info.S b/arch/x86/boot/compressed/kernel_info.S
index 8ea6f6e3feef..018dacbd753e 100644
--- a/arch/x86/boot/compressed/kernel_info.S
+++ b/arch/x86/boot/compressed/kernel_info.S
@@ -1,5 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */

+#include <asm/bootparam.h>
+
.section ".rodata.kernel_info", "a"

.global kernel_info
@@ -12,6 +14,9 @@ kernel_info:
/* Size total. */
.long kernel_info_end - kernel_info

+ /* Maximal allowed type for setup_data. */
+ .long SETUP_TYPE_MAX
+
kernel_info_var_len_data:
/* Empty for time being... */
kernel_info_end:
diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index a1ebcd7a991c..dbb41128e5a0 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -11,6 +11,9 @@
#define SETUP_APPLE_PROPERTIES 5
#define SETUP_JAILHOUSE 6

+/* max(SETUP_*) */
+#define SETUP_TYPE_MAX SETUP_JAILHOUSE
+
/* ram_size flags */
#define RAMDISK_IMAGE_START_MASK 0x07FF
#define RAMDISK_PROMPT_FLAG 0x8000
--
2.11.0