4 files changed, 65 insertions, 10 deletions

diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index 286f6a624c3..1faae5fc1c0 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)
 {
diff --git a/arch/x86_64/mm/ioremap.c b/arch/x86_64/mm/ioremap.c
index ecf7acb5db9..ae207064201 100644
--- a/arch/x86_64/mm/ioremap.c
+++ b/arch/x86_64/mm/ioremap.c
@@ -247,9 +247,15 @@ void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
 	return __ioremap(phys_addr, size, _PAGE_PCD);
 }
 
+/**
+ * iounmap - Free a IO remapping
+ * @addr: virtual address from ioremap_*
+ *
+ * Caller must ensure there is only one unmapping for the same pointer.
+ */
 void iounmap(volatile void __iomem *addr)
 {
-	struct vm_struct *p;
+	struct vm_struct *p, *o;
 
 	if (addr <= high_memory) 
 		return; 
@@ -257,12 +263,31 @@ void iounmap(volatile void __iomem *addr)
 		addr < phys_to_virt(ISA_END_ADDRESS))
 		return;
 
-	write_lock(&vmlist_lock);
-	p = __remove_vm_area((void *)((unsigned long)addr & PAGE_MASK));
-	if (!p)
+	addr = (volatile void __iomem *)(PAGE_MASK & (unsigned long __force)addr);
+	/* Use the vm area unlocked, assuming the caller
+	   ensures there isn't another iounmap for the same address
+	   in parallel. Reuse of the virtual address is prevented by
+	   leaving it in the global lists until we're done with it.
+	   cpa takes care of the direct mappings. */
+	read_lock(&vmlist_lock);
+	for (p = vmlist; p; p = p->next) {
+		if (p->addr == addr)
+			break;
+	}
+	read_unlock(&vmlist_lock);
+
+	if (!p) {
 		printk("iounmap: bad address %p\n", addr);
-	else if (p->flags >> 20)
+		dump_stack();
+		return;
+	}
+
+	/* Reset the direct mapping. Can block */
+	if (p->flags >> 20)
 		ioremap_change_attr(p->phys_addr, p->size, 0);
-	write_unlock(&vmlist_lock);
+
+	/* Finally remove it */
+	o = remove_vm_area((void *)addr);
+	BUG_ON(p != o || o == NULL);
 	kfree(p); 
 }
diff --git a/arch/x86_64/mm/numa.c b/arch/x86_64/mm/numa.c
index a828a01739c..15b67d2760c 100644
--- a/arch/x86_64/mm/numa.c
+++ b/arch/x86_64/mm/numa.c
@@ -53,6 +53,8 @@ static int __init populate_memnodemap(
 	int res = -1;
 	unsigned long addr, end;
 
+	if (shift >= 64)
+		return -1;
 	memset(memnodemap, 0xff, sizeof(memnodemap));
 	for (i = 0; i < numnodes; i++) {
 		addr = nodes[i].start;
@@ -65,7 +67,7 @@ static int __init populate_memnodemap(
 			if (memnodemap[addr >> shift] != 0xff)
 				return -1;
 			memnodemap[addr >> shift] = i;
-			addr += (1 << shift);
+                       addr += (1UL << shift);
 		} while (addr < end);
 		res = 1;
 	} 
diff --git a/arch/x86_64/mm/pageattr.c b/arch/x86_64/mm/pageattr.c
index b90e8fe9eeb..35f1f1aab06 100644
--- a/arch/x86_64/mm/pageattr.c
+++ b/arch/x86_64/mm/pageattr.c
@@ -128,6 +128,7 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
 	pte_t *kpte; 
 	struct page *kpte_page;
 	unsigned kpte_flags;
+	pgprot_t ref_prot2;
 	kpte = lookup_address(address);
 	if (!kpte) return 0;
 	kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
@@ -140,10 +141,14 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
  			 * split_large_page will take the reference for this change_page_attr
  			 * on the split page.
  			 */
-			struct page *split = split_large_page(address, prot, ref_prot); 
+
+			struct page *split;
+			ref_prot2 = __pgprot(pgprot_val(pte_pgprot(*lookup_address(address))) & ~(1<<_PAGE_BIT_PSE));
+
+			split = split_large_page(address, prot, ref_prot2);
 			if (!split)
 				return -ENOMEM;
-			set_pte(kpte,mk_pte(split, ref_prot));
+			set_pte(kpte,mk_pte(split, ref_prot2));
 			kpte_page = split;
 		}	
 		get_page(kpte_page);