From 92bb8d5d55f7fe1a7a1201c42120c1611840807c Mon Sep 17 00:00:00 2001
From: Jisheng Zhang <jszhang@marvell.com>
Date: Mon, 15 Aug 2016 09:20:21 +0100
Subject: [PATCH] ARM: 8597/1: VDSO: put RO and RO after init objects into
proper sections
vdso_data_mapping is never modified, so mark it as const.
vdso_total_pages, vdso_data_page, vdso_text_mapping and cntvct_ok are
initialized by vdso_init(), thereafter are read only.
The fact that they are read only after init makes them candidates for
__ro_after_init declarations.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
arch/arm/kernel/vdso.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c
index 994e971a8538..bbbffe946122 100644
--- a/arch/arm/kernel/vdso.c
+++ b/arch/arm/kernel/vdso.c
@@ -17,6 +17,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/cache.h>
#include <linux/elf.h>
#include <linux/err.h>
#include <linux/kernel.h>
@@ -39,7 +40,7 @@
static struct page **vdso_text_pagelist;
/* Total number of pages needed for the data and text portions of the VDSO. */
-unsigned int vdso_total_pages __read_mostly;
+unsigned int vdso_total_pages __ro_after_init;
/*
* The VDSO data page.
@@ -47,13 +48,13 @@ unsigned int vdso_total_pages __read_mostly;
static union vdso_data_store vdso_data_store __page_aligned_data;
static struct vdso_data *vdso_data = &vdso_data_store.data;
-static struct page *vdso_data_page;
-static struct vm_special_mapping vdso_data_mapping = {
+static struct page *vdso_data_page __ro_after_init;
+static const struct vm_special_mapping vdso_data_mapping = {
.name = "[vvar]",
.pages = &vdso_data_page,
};
-static struct vm_special_mapping vdso_text_mapping = {
+static struct vm_special_mapping vdso_text_mapping __ro_after_init = {
.name = "[vdso]",
};
@@ -67,7 +68,7 @@ struct elfinfo {
/* Cached result of boot-time check for whether the arch timer exists,
* and if so, whether the virtual counter is useable.
*/
-static bool cntvct_ok __read_mostly;
+static bool cntvct_ok __ro_after_init;
static bool __init cntvct_functional(void)
{
--
2.30.9