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Diffstat (limited to 'arch/x86/mm')
-rw-r--r--arch/x86/mm/init_32.c35
-rw-r--r--arch/x86/mm/init_64.c37
2 files changed, 64 insertions, 8 deletions
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index db81e9a8556..749559ed80f 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -1054,17 +1054,47 @@ static noinline int do_test_wp_bit(void)
const int rodata_test_data = 0xC3;
EXPORT_SYMBOL_GPL(rodata_test_data);
+static int kernel_set_to_readonly;
+
+void set_kernel_text_rw(void)
+{
+ unsigned long start = PFN_ALIGN(_text);
+ unsigned long size = PFN_ALIGN(_etext) - start;
+
+ if (!kernel_set_to_readonly)
+ return;
+
+ pr_debug("Set kernel text: %lx - %lx for read write\n",
+ start, start+size);
+
+ set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT);
+}
+
+void set_kernel_text_ro(void)
+{
+ unsigned long start = PFN_ALIGN(_text);
+ unsigned long size = PFN_ALIGN(_etext) - start;
+
+ if (!kernel_set_to_readonly)
+ return;
+
+ pr_debug("Set kernel text: %lx - %lx for read only\n",
+ start, start+size);
+
+ set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
+}
+
void mark_rodata_ro(void)
{
unsigned long start = PFN_ALIGN(_text);
unsigned long size = PFN_ALIGN(_etext) - start;
-#ifndef CONFIG_DYNAMIC_FTRACE
- /* Dynamic tracing modifies the kernel text section */
set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
printk(KERN_INFO "Write protecting the kernel text: %luk\n",
size >> 10);
+ kernel_set_to_readonly = 1;
+
#ifdef CONFIG_CPA_DEBUG
printk(KERN_INFO "Testing CPA: Reverting %lx-%lx\n",
start, start+size);
@@ -1073,7 +1103,6 @@ void mark_rodata_ro(void)
printk(KERN_INFO "Testing CPA: write protecting again\n");
set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT);
#endif
-#endif /* CONFIG_DYNAMIC_FTRACE */
start += size;
size = (unsigned long)__end_rodata - start;
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 54efa57d1c0..1753e8020df 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -734,21 +734,48 @@ void __init mem_init(void)
const int rodata_test_data = 0xC3;
EXPORT_SYMBOL_GPL(rodata_test_data);
+static int kernel_set_to_readonly;
+
+void set_kernel_text_rw(void)
+{
+ unsigned long start = PFN_ALIGN(_stext);
+ unsigned long end = PFN_ALIGN(__start_rodata);
+
+ if (!kernel_set_to_readonly)
+ return;
+
+ pr_debug("Set kernel text: %lx - %lx for read write\n",
+ start, end);
+
+ set_memory_rw(start, (end - start) >> PAGE_SHIFT);
+}
+
+void set_kernel_text_ro(void)
+{
+ unsigned long start = PFN_ALIGN(_stext);
+ unsigned long end = PFN_ALIGN(__start_rodata);
+
+ if (!kernel_set_to_readonly)
+ return;
+
+ pr_debug("Set kernel text: %lx - %lx for read only\n",
+ start, end);
+
+ set_memory_ro(start, (end - start) >> PAGE_SHIFT);
+}
+
void mark_rodata_ro(void)
{
unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
unsigned long rodata_start =
((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
-#ifdef CONFIG_DYNAMIC_FTRACE
- /* Dynamic tracing modifies the kernel text section */
- start = rodata_start;
-#endif
-
printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
(end - start) >> 10);
set_memory_ro(start, (end - start) >> PAGE_SHIFT);
+ kernel_set_to_readonly = 1;
+
/*
* The rodata section (but not the kernel text!) should also be
* not-executable.