6 files changed, 40 insertions, 23 deletions

diff --git a/arch/i386/kernel/vmlinux.lds.S b/arch/i386/kernel/vmlinux.lds.S
index 6f38f818380b..f4ec72231835 100644
--- a/arch/i386/kernel/vmlinux.lds.S
+++ b/arch/i386/kernel/vmlinux.lds.S
@@ -61,8 +61,6 @@ SECTIONS
         __stop___ex_table = .;
   }
 
-  RODATA
-
   BUG_TABLE
 
   . = ALIGN(4);
@@ -72,6 +70,8 @@ SECTIONS
         __tracedata_end = .;
   }
 
+  RODATA
+
   /* writeable */
   . = ALIGN(4096);
   .data : AT(ADDR(.data) - LOAD_OFFSET) {       /* Data */
diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c
index 23be1b0aafa4..bd5ef3718504 100644
--- a/arch/i386/mm/init.c
+++ b/arch/i386/mm/init.c
@@ -22,6 +22,7 @@
 #include <linux/init.h>
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
+#include <linux/pfn.h>
 #include <linux/poison.h>
 #include <linux/bootmem.h>
 #include <linux/slab.h>
@@ -751,13 +752,25 @@ static int noinline do_test_wp_bit(void)
 
 void mark_rodata_ro(void)
 {
-        unsigned long addr = (unsigned long)__start_rodata;
+        unsigned long start = PFN_ALIGN(_text);
+        unsigned long size = PFN_ALIGN(_etext) - start;
 
-        for (; addr < (unsigned long)__end_rodata; addr += PAGE_SIZE)
-                change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RO);
+#ifdef CONFIG_HOTPLUG_CPU
+        /* It must still be possible to apply SMP alternatives. */
+        if (num_possible_cpus() <= 1)
+#endif
+        {
+                change_page_attr(virt_to_page(start),
+                                 size >> PAGE_SHIFT, PAGE_KERNEL_RX);
+                printk("Write protecting the kernel text: %luk\n", size >> 10);
+        }
 
-        printk("Write protecting the kernel read-only data: %uk\n",
-                        (__end_rodata - __start_rodata) >> 10);
+        start += size;
+        size = (unsigned long)__end_rodata - start;
+        change_page_attr(virt_to_page(start),
+                         size >> PAGE_SHIFT, PAGE_KERNEL_RO);
+        printk("Write protecting the kernel read-only data: %luk\n",
+               size >> 10);
 
         /*
          * change_page_attr() requires a global_flush_tlb() call after it.
@@ -781,7 +794,7 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
                 __free_page(page);
                 totalram_pages++;
         }
-        printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
+        printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
 }
 
 void free_initmem(void)
diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S
index 36aa98a6d15c..fd9fdfdd143e 100644
--- a/arch/x86_64/kernel/head.S
+++ b/arch/x86_64/kernel/head.S
@@ -280,7 +280,6 @@ early_idt_ripmsg:
 
 .balign PAGE_SIZE
 ENTRY(stext)
-ENTRY(_stext)
 
 #define NEXT_PAGE(name) \
         .balign PAGE_SIZE; \
diff --git a/arch/x86_64/kernel/vmlinux.lds.S b/arch/x86_64/kernel/vmlinux.lds.S
index 5176ecf006ee..3bdeb88d28f4 100644
--- a/arch/x86_64/kernel/vmlinux.lds.S
+++ b/arch/x86_64/kernel/vmlinux.lds.S
@@ -29,6 +29,7 @@ SECTIONS
   .text :  AT(ADDR(.text) - LOAD_OFFSET) {
         /* First the code that has to be first for bootstrapping */
         *(.bootstrap.text)
+        _stext = .;
         /* Then all the functions that are "hot" in profiles, to group them
            onto the same hugetlb entry */
         #include "functionlist"
@@ -50,10 +51,10 @@ SECTIONS
   __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { *(__ex_table) }
   __stop___ex_table = .;
 
-  RODATA
-
   BUG_TABLE
 
+  RODATA
+
   . = ALIGN(PAGE_SIZE);        /* Align data segment to page size boundary */
                                 /* Data */
   .data : AT(ADDR(.data) - LOAD_OFFSET) {
diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index 69e22d3c9238..e3134bc9a4fc 100644
--- a/arch/x86_64/mm/init.c
+++ b/arch/x86_64/mm/init.c
@@ -22,6 +22,7 @@
 #include <linux/bootmem.h>
 #include <linux/proc_fs.h>
 #include <linux/pci.h>
+#include <linux/pfn.h>
 #include <linux/poison.h>
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
@@ -563,21 +564,23 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
         if (begin >= end)
                 return;
 
-        printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
+        printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
         for (addr = begin; addr < end; addr += PAGE_SIZE) {
                 struct page *page = pfn_to_page(addr >> PAGE_SHIFT);
                 ClearPageReserved(page);
                 init_page_count(page);
                 memset(page_address(page), POISON_FREE_INITMEM, PAGE_SIZE);
+                if (addr >= __START_KERNEL_map)
+                        change_page_attr_addr(addr, 1, __pgprot(0));
                 __free_page(page);
                 totalram_pages++;
         }
+        if (addr > __START_KERNEL_map)
+                global_flush_tlb();
 }
 
 void free_initmem(void)
 {
-        memset(__initdata_begin, POISON_FREE_INITDATA,
-                __initdata_end - __initdata_begin);
         free_init_pages("unused kernel memory",
                         __pa_symbol(&__init_begin),
                         __pa_symbol(&__init_end));
@@ -587,14 +590,18 @@ void free_initmem(void)
 
 void mark_rodata_ro(void)
 {
-        unsigned long addr = (unsigned long)__va(__pa_symbol(&__start_rodata));
-        unsigned long end  = (unsigned long)__va(__pa_symbol(&__end_rodata));
+        unsigned long start = PFN_ALIGN(__va(__pa_symbol(&_stext))), size;
 
-        for (; addr < end; addr += PAGE_SIZE)
-                change_page_attr_addr(addr, 1, PAGE_KERNEL_RO);
+#ifdef CONFIG_HOTPLUG_CPU
+        /* It must still be possible to apply SMP alternatives. */
+        if (num_possible_cpus() > 1)
+                start = PFN_ALIGN(__va(__pa_symbol(&_etext)));
+#endif
+        size = (unsigned long)__va(__pa_symbol(&__end_rodata)) - start;
+        change_page_attr_addr(start, size >> PAGE_SHIFT, PAGE_KERNEL_RO);
 
-        printk ("Write protecting the kernel read-only data: %luk\n",
-                        (__end_rodata - __start_rodata) >> 10);
+        printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
+               size >> 10);
 
         /*
          * change_page_attr_addr() requires a global_flush_tlb() call after it.
diff --git a/include/linux/poison.h b/include/linux/poison.h
index 3e628f990fdf..89580b764959 100644
--- a/include/linux/poison.h
+++ b/include/linux/poison.h
@@ -26,9 +26,6 @@
 /********** arch/$ARCH/mm/init.c **********/
 #define POISON_FREE_INITMEM     0xcc
 
-/********** arch/x86_64/mm/init.c **********/
-#define POISON_FREE_INITDATA    0xba
-
 /********** arch/ia64/hp/common/sba_iommu.c **********/
 /*
  * arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a