1 files changed, 28 insertions, 2 deletions

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 237aaa488f4e..1e9c30b241c3 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -386,8 +386,6 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill,
         struct task_struct *tsk;
         struct anon_vma *av;
 
-        if (!PageHuge(page) && unlikely(split_huge_page(page)))
-                return;
         read_lock(&tasklist_lock);
         av = page_lock_anon_vma(page);
         if (av == NULL) /* Not actually mapped anymore */
@@ -896,6 +894,34 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
                 }
         }
 
+        if (PageTransHuge(hpage)) {
+                /*
+                 * Verify that this isn't a hugetlbfs head page, the check for
+                 * PageAnon is just for avoid tripping a split_huge_page
+                 * internal debug check, as split_huge_page refuses to deal with
+                 * anything that isn't an anon page. PageAnon can't go away fro
+                 * under us because we hold a refcount on the hpage, without a
+                 * refcount on the hpage. split_huge_page can't be safely called
+                 * in the first place, having a refcount on the tail isn't
+                 * enough * to be safe.
+                 */
+                if (!PageHuge(hpage) && PageAnon(hpage)) {
+                        if (unlikely(split_huge_page(hpage))) {
+                                /*
+                                 * FIXME: if splitting THP is failed, it is
+                                 * better to stop the following operation rather
+                                 * than causing panic by unmapping. System might
+                                 * survive if the page is freed later.
+                                 */
+                                printk(KERN_INFO
+                                        "MCE %#lx: failed to split THP\n", pfn);
+
+                                BUG_ON(!PageHWPoison(p));
+                                return SWAP_FAIL;
+                        }
+                }
+        }
+
         /*
          * First collect all the processes that have the page
          * mapped in dirty form.  This has to be done before try_to_unmap,