Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / mm / memory-failure.c

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 393ea13..9588269 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -130,27 +130,15 @@ static int hwpoison_filter_flags(struct page *p)
  * can only guarantee that the page either belongs to the memcg tasks, or is
  * a freed page.
  */
-#ifdef CONFIG_MEMCG_SWAP
+#ifdef CONFIG_MEMCG
 u64 hwpoison_filter_memcg;
 EXPORT_SYMBOL_GPL(hwpoison_filter_memcg);
 static int hwpoison_filter_task(struct page *p)
 {
-       struct mem_cgroup *mem;
-       struct cgroup_subsys_state *css;
-       unsigned long ino;
-
        if (!hwpoison_filter_memcg)
                return 0;
 
-       mem = try_get_mem_cgroup_from_page(p);
-       if (!mem)
-               return -EINVAL;
-
-       css = &mem->css;
-       ino = cgroup_ino(css->cgroup);
-       css_put(css);
-
-       if (ino != hwpoison_filter_memcg)
+       if (page_cgroup_ino(p) != hwpoison_filter_memcg)
                return -EINVAL;
 
        return 0;
@@ -1445,6 +1433,22 @@ int unpoison_memory(unsigned long pfn)
                return 0;
        }
 
+       if (page_count(page) > 1) {
+               pr_info("MCE: Someone grabs the hwpoison page %#lx\n", pfn);
+               return 0;
+       }
+
+       if (page_mapped(page)) {
+               pr_info("MCE: Someone maps the hwpoison page %#lx\n", pfn);
+               return 0;
+       }
+
+       if (page_mapping(page)) {
+               pr_info("MCE: the hwpoison page has non-NULL mapping %#lx\n",
+                       pfn);
+               return 0;
+       }
+
        /*
         * unpoison_memory() can encounter thp only when the thp is being
         * worked by memory_failure() and the page lock is not held yet.
@@ -1505,7 +1509,7 @@ static struct page *new_page(struct page *p, unsigned long private, int **x)
                return alloc_huge_page_node(page_hstate(compound_head(p)),
                                                   nid);
        else
-               return alloc_pages_exact_node(nid, GFP_HIGHUSER_MOVABLE, 0);
+               return __alloc_pages_node(nid, GFP_HIGHUSER_MOVABLE, 0);
 }
 
 /*
@@ -1681,8 +1685,6 @@ static int __soft_offline_page(struct page *page, int flags)
                inc_zone_page_state(page, NR_ISOLATED_ANON +
                                        page_is_file_cache(page));
                list_add(&page->lru, &pagelist);
-               if (!TestSetPageHWPoison(page))
-                       num_poisoned_pages_dec();
                ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
                                        MIGRATE_SYNC, MR_MEMORY_FAILURE);
                if (ret) {
@@ -1697,8 +1699,6 @@ static int __soft_offline_page(struct page *page, int flags)
                                pfn, ret, page->flags);
                        if (ret > 0)
                                ret = -EIO;
-                       if (TestClearPageHWPoison(page))
-                               num_poisoned_pages_dec();
                }
        } else {
                pr_info("soft offline: %#lx: isolation failed: %d, page count %d, type %lx\n",