Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "4 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, page_alloc: fix has_unmovable_pages for HugePages
  fork,memcg: fix crash in free_thread_stack on memcg charge fail
  mm: thp: fix flags for pmd migration when split
  mm, memory_hotplug: initialize struct pages for the full memory section

1 files changed, 17 insertions, 2 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2ec9cc407216..e95b5b7c9c3d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5542,6 +5542,18 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 			cond_resched();
 		}
 	}
+#ifdef CONFIG_SPARSEMEM
+	/*
+	 * If the zone does not span the rest of the section then
+	 * we should at least initialize those pages. Otherwise we
+	 * could blow up on a poisoned page in some paths which depend
+	 * on full sections being initialized (e.g. memory hotplug).
+	 */
+	while (end_pfn % PAGES_PER_SECTION) {
+		__init_single_page(pfn_to_page(end_pfn), end_pfn, zone, nid);
+		end_pfn++;
+	}
+#endif
 }
 
 #ifdef CONFIG_ZONE_DEVICE
@@ -7802,11 +7814,14 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		 * handle each tail page individually in migration.
 		 */
 		if (PageHuge(page)) {
+			struct page *head = compound_head(page);
+			unsigned int skip_pages;
 
-			if (!hugepage_migration_supported(page_hstate(page)))
+			if (!hugepage_migration_supported(page_hstate(head)))
 				goto unmovable;
 
-			iter = round_up(iter + 1, 1<<compound_order(page)) - 1;
+			skip_pages = (1 << compound_order(head)) - (page - head);
+			iter += skip_pages - 1;
 			continue;
 		}