1 files changed, 24 insertions, 1 deletions

diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index 286f6a624c3a..1faae5fc1c01 100644
--- a/arch/x86_64/mm/init.c
+++ b/arch/x86_64/mm/init.c
@@ -348,7 +348,7 @@ size_zones(unsigned long *z, unsigned long *h,
         }
 
         /* Compute holes */
-        w = 0;
+        w = start_pfn;
         for (i = 0; i < MAX_NR_ZONES; i++) {
                 unsigned long s = w;
                 w += z[i];
@@ -498,6 +498,29 @@ void free_initmem(void)
         printk ("Freeing unused kernel memory: %luk freed\n", (__init_end - __init_begin) >> 10);
 }
 
+#ifdef CONFIG_DEBUG_RODATA
+
+extern char __start_rodata, __end_rodata;
+void mark_rodata_ro(void)
+{
+        unsigned long addr = (unsigned long)&__start_rodata;
+
+        for (; addr < (unsigned long)&__end_rodata; addr += PAGE_SIZE)
+                change_page_attr_addr(addr, 1, PAGE_KERNEL_RO);
+
+        printk ("Write protecting the kernel read-only data: %luk\n",
+                        (&__end_rodata - &__start_rodata) >> 10);
+
+        /*
+         * change_page_attr_addr() requires a global_flush_tlb() call after it.
+         * We do this after the printk so that if something went wrong in the
+         * change, the printk gets out at least to give a better debug hint
+         * of who is the culprit.
+         */
+        global_flush_tlb();
+}
+#endif
+
 #ifdef CONFIG_BLK_DEV_INITRD
 void free_initrd_mem(unsigned long start, unsigned long end)
 {