mm/memunmap: don't access uninitialized memmap in memunmap_pages()

[linux-2.6-block.git] / fs / proc / page.c

diff --git a/fs/proc/page.c b/fs/proc/page.c
index 544d1ee15aeece96efa3e5b39a9481c879584419..7c952ee732e63dffd0ae09f92a6ec3e6c57e5771 100644 (file)
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -42,10 +42,12 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
                return -EINVAL;
 
        while (count > 0) {
-               if (pfn_valid(pfn))
-                       ppage = pfn_to_page(pfn);
-               else
-                       ppage = NULL;
+               /*
+                * TODO: ZONE_DEVICE support requires to identify
+                * memmaps that were actually initialized.
+                */
+               ppage = pfn_to_online_page(pfn);
+
                if (!ppage || PageSlab(ppage) || page_has_type(ppage))
                        pcount = 0;
                else
@@ -216,10 +218,11 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf,
                return -EINVAL;
 
        while (count > 0) {
-               if (pfn_valid(pfn))
-                       ppage = pfn_to_page(pfn);
-               else
-                       ppage = NULL;
+               /*
+                * TODO: ZONE_DEVICE support requires to identify
+                * memmaps that were actually initialized.
+                */
+               ppage = pfn_to_online_page(pfn);
 
                if (put_user(stable_page_flags(ppage), out)) {
                        ret = -EFAULT;
@@ -261,10 +264,11 @@ static ssize_t kpagecgroup_read(struct file *file, char __user *buf,
                return -EINVAL;
 
        while (count > 0) {
-               if (pfn_valid(pfn))
-                       ppage = pfn_to_page(pfn);
-               else
-                       ppage = NULL;
+               /*
+                * TODO: ZONE_DEVICE support requires to identify
+                * memmaps that were actually initialized.
+                */
+               ppage = pfn_to_online_page(pfn);
 
                if (ppage)
                        ino = page_cgroup_ino(ppage);