x86/boot: Introduce kernel_info.setup_type_max

This field contains maximal allowed type for setup_data. Do 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) <[email protected]> Signed-off-by: Daniel Kiper <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Konrad Rzeszutek Wilk <[email protected]> Reviewed-by: Ross Philipson <[email protected]> Reviewed-by: H. Peter Anvin (Intel) <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: [email protected] Cc: Boris Ostrovsky <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Ingo Molnar <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Juergen Gross <[email protected]> Cc: [email protected] Cc: [email protected] Cc: linux-efi <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Thomas Gleixner <[email protected]> Cc: x86-ml <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
beagleboard · Nov 12, 2019 · 00cd1c1 · 00cd1c1
1 parent 2c33c27
commit 00cd1c1
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diff --git 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:	0x000c/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
@@ -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
@@ -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