mm: compaction: encapsulate defer reset logic

[firefly-linux-kernel-4.4.55.git] / mm / memory-failure.c

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index db08af92c6fce92d9e0d61ca5752aa003c52c3f2..9fa6586d52752a81bea7f71343687b959049fd7d 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -611,7 +611,7 @@ static int me_pagecache_clean(struct page *p, unsigned long pfn)
 }
 
 /*
- * Dirty cache page page
+ * Dirty pagecache page
  * Issues: when the error hit a hole page the error is not properly
  * propagated.
  */
@@ -938,6 +938,16 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
                                BUG_ON(!PageHWPoison(p));
                                return SWAP_FAIL;
                        }
+                       /*
+                        * We pinned the head page for hwpoison handling,
+                        * now we split the thp and we are interested in
+                        * the hwpoisoned raw page, so move the refcount
+                        * to it.
+                        */
+                       if (hpage != p) {
+                               put_page(hpage);
+                               get_page(p);
+                       }
                        /* THP is split, so ppage should be the real poisoned page. */
                        ppage = p;
                }