3 files changed, 35 insertions, 38 deletions

diff --git a/arch/parisc/include/asm/cache.h b/arch/parisc/include/asm/cache.h
index 4016fe1c65a9..73ca89a47f49 100644
--- a/arch/parisc/include/asm/cache.h
+++ b/arch/parisc/include/asm/cache.h
@@ -24,9 +24,6 @@
 
 #define __read_mostly __attribute__((__section__(".data..read_mostly")))
 
-/* Read-only memory is marked before mark_rodata_ro() is called. */
-#define __ro_after_init __read_mostly
-
 void parisc_cache_init(void);   /* initializes cache-flushing */
 void disable_sr_hashing_asm(int); /* low level support for above */
 void disable_sr_hashing(void);   /* turns off space register hashing */
diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S
index a8be7a47fcc0..c3b1b9c24ede 100644
--- a/arch/parisc/kernel/vmlinux.lds.S
+++ b/arch/parisc/kernel/vmlinux.lds.S
@@ -18,9 +18,6 @@
                                 *(.data..vm0.pgd) \
                                 *(.data..vm0.pte)
 
-/* No __ro_after_init data in the .rodata section - which will always be ro */
-#define RO_AFTER_INIT_DATA
-
 #include <asm-generic/vmlinux.lds.h>
 
 /* needed for the processor specific cache alignment size */    
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 3b0f9eab7f2c..b99bcbf1ecdb 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -345,16 +345,7 @@ static void __init setup_bootmem(void)
         memblock_dump_all();
 }
 
-static int __init parisc_text_address(unsigned long vaddr)
-{
-        static unsigned long head_ptr __initdata;
-
-        if (!head_ptr)
-                head_ptr = PAGE_MASK & (unsigned long)
-                        dereference_function_descriptor(&parisc_kernel_start);
-
-        return core_kernel_text(vaddr) || vaddr == head_ptr;
-}
+static bool kernel_set_to_readonly;
 
 static void __init map_pages(unsigned long start_vaddr,
                              unsigned long start_paddr, unsigned long size,
@@ -372,10 +363,11 @@ static void __init map_pages(unsigned long start_vaddr,
         unsigned long vaddr;
         unsigned long ro_start;
         unsigned long ro_end;
-        unsigned long kernel_end;
+        unsigned long kernel_start, kernel_end;
 
         ro_start = __pa((unsigned long)_text);
         ro_end   = __pa((unsigned long)&data_start);
+        kernel_start = __pa((unsigned long)&__init_begin);
         kernel_end  = __pa((unsigned long)&_end);
 
         end_paddr = start_paddr + size;
@@ -438,26 +430,30 @@ static void __init map_pages(unsigned long start_vaddr,
                         pg_table = (pte_t *) __va(pg_table) + start_pte;
                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
                                 pte_t pte;
-
-                                if (force)
-                                        pte =  __mk_pte(address, pgprot);
-                                else if (parisc_text_address(vaddr)) {
-                                        pte = __mk_pte(address, PAGE_KERNEL_EXEC);
-                                        if (address >= ro_start && address < kernel_end)
-                                                pte = pte_mkhuge(pte);
+                                pgprot_t prot;
+                                bool huge = false;
+
+                                if (force) {
+                                        prot = pgprot;
+                                } else if (address < kernel_start || address >= kernel_end) {
+                                        /* outside kernel memory */
+                                        prot = PAGE_KERNEL;
+                                } else if (!kernel_set_to_readonly) {
+                                        /* still initializing, allow writing to RO memory */
+                                        prot = PAGE_KERNEL_RWX;
+                                        huge = true;
+                                } else if (address >= ro_start) {
+                                        /* Code (ro) and Data areas */
+                                        prot = (address < ro_end) ?
+                                                PAGE_KERNEL_EXEC : PAGE_KERNEL;
+                                        huge = true;
+                                } else {
+                                        prot = PAGE_KERNEL;
                                 }
-                                else
-#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
-                                if (address >= ro_start && address < ro_end) {
-                                        pte = __mk_pte(address, PAGE_KERNEL_EXEC);
+
+                                pte = __mk_pte(address, prot);
+                                if (huge)
                                         pte = pte_mkhuge(pte);
-                                } else
-#endif
-                                {
-                                        pte = __mk_pte(address, pgprot);
-                                        if (address >= ro_start && address < kernel_end)
-                                                pte = pte_mkhuge(pte);
-                                }
 
                                 if (address >= end_paddr)
                                         break;
@@ -493,6 +489,12 @@ void __ref free_initmem(void)
 {
         unsigned long init_begin = (unsigned long)__init_begin;
         unsigned long init_end = (unsigned long)__init_end;
+        unsigned long kernel_end  = (unsigned long)&_end;
+
+        /* Remap kernel text and data, but do not touch init section yet. */
+        kernel_set_to_readonly = true;
+        map_pages(init_end, __pa(init_end), kernel_end - init_end,
+                  PAGE_KERNEL, 0);
 
         /* The init text pages are marked R-X.  We have to
          * flush the icache and mark them RW-
@@ -509,7 +511,7 @@ void __ref free_initmem(void)
                   PAGE_KERNEL, 1);
 
         /* force the kernel to see the new TLB entries */
-        __flush_tlb_range(0, init_begin, init_end);
+        __flush_tlb_range(0, init_begin, kernel_end);
 
         /* finally dump all the instructions which were cached, since the
          * pages are no-longer executable */
@@ -527,8 +529,9 @@ void mark_rodata_ro(void)
 {
         /* rodata memory was already mapped with KERNEL_RO access rights by
            pagetable_init() and map_pages(). No need to do additional stuff here */
-        printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
-                (unsigned long)(__end_rodata - __start_rodata) >> 10);
+        unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
+
+        pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
 }
 #endif