4 files changed, 29 insertions, 23 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 000a220e2a41..088358c8006b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -257,9 +257,11 @@ static int filemap_check_errors(struct address_space *mapping)
 {
         int ret = 0;
         /* Check for outstanding write errors */
-        if (test_and_clear_bit(AS_ENOSPC, &mapping->flags))
+        if (test_bit(AS_ENOSPC, &mapping->flags) &&
+            test_and_clear_bit(AS_ENOSPC, &mapping->flags))
                 ret = -ENOSPC;
-        if (test_and_clear_bit(AS_EIO, &mapping->flags))
+        if (test_bit(AS_EIO, &mapping->flags) &&
+            test_and_clear_bit(AS_EIO, &mapping->flags))
                 ret = -EIO;
         return ret;
 }
diff --git a/mm/madvise.c b/mm/madvise.c
index 539eeb96b323..a402f8fdc68e 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -195,7 +195,7 @@ static void force_shm_swapin_readahead(struct vm_area_struct *vma,
         for (; start < end; start += PAGE_SIZE) {
                 index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
 
-                page = find_get_page(mapping, index);
+                page = find_get_entry(mapping, index);
                 if (!radix_tree_exceptional_entry(page)) {
                         if (page)
                                 page_cache_release(page);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c47dffdcb246..5177c6d4a2dd 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1077,9 +1077,18 @@ static struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
 
         rcu_read_lock();
         do {
-                memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
-                if (unlikely(!memcg))
+                /*
+                 * Page cache insertions can happen withou an
+                 * actual mm context, e.g. during disk probing
+                 * on boot, loopback IO, acct() writes etc.
+                 */
+                if (unlikely(!mm))
                         memcg = root_mem_cgroup;
+                else {
+                        memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
+                        if (unlikely(!memcg))
+                                memcg = root_mem_cgroup;
+                }
         } while (!css_tryget(&memcg->css));
         rcu_read_unlock();
         return memcg;
@@ -3958,17 +3967,9 @@ int mem_cgroup_charge_file(struct page *page, struct mm_struct *mm,
                 return 0;
         }
 
-        /*
-         * Page cache insertions can happen without an actual mm
-         * context, e.g. during disk probing on boot.
-         */
-        if (unlikely(!mm))
-                memcg = root_mem_cgroup;
-        else {
-                memcg = mem_cgroup_try_charge_mm(mm, gfp_mask, 1, true);
-                if (!memcg)
-                        return -ENOMEM;
-        }
+        memcg = mem_cgroup_try_charge_mm(mm, gfp_mask, 1, true);
+        if (!memcg)
+                return -ENOMEM;
         __mem_cgroup_commit_charge(memcg, page, 1, type, false);
         return 0;
 }
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 35ef28acf137..9ccef39a9de2 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1081,15 +1081,16 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
                         return 0;
                 } else if (PageHuge(hpage)) {
                         /*
-                         * Check "just unpoisoned", "filter hit", and
-                         * "race with other subpage."
+                         * Check "filter hit" and "race with other subpage."
                          */
                         lock_page(hpage);
-                        if (!PageHWPoison(hpage)
-                            || (hwpoison_filter(p) && TestClearPageHWPoison(p))
-                            || (p != hpage && TestSetPageHWPoison(hpage))) {
-                                atomic_long_sub(nr_pages, &num_poisoned_pages);
-                                return 0;
+                        if (PageHWPoison(hpage)) {
+                                if ((hwpoison_filter(p) && TestClearPageHWPoison(p))
+                                    || (p != hpage && TestSetPageHWPoison(hpage))) {
+                                        atomic_long_sub(nr_pages, &num_poisoned_pages);
+                                        unlock_page(hpage);
+                                        return 0;
+                                }
                         }
                         set_page_hwpoison_huge_page(hpage);
                         res = dequeue_hwpoisoned_huge_page(hpage);
@@ -1152,6 +1153,8 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
          */
         if (!PageHWPoison(p)) {
                 printk(KERN_ERR "MCE %#lx: just unpoisoned\n", pfn);
+                atomic_long_sub(nr_pages, &num_poisoned_pages);
+                put_page(hpage);
                 res = 0;
                 goto out;
         }