5 files changed, 53 insertions, 18 deletions

diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 76a9539cfd3f..a92061e08d48 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -2,7 +2,8 @@
 #define __LINUX_PAGEISOLATION_H
 
 
-bool has_unmovable_pages(struct zone *zone, struct page *page, int count);
+bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
+                         bool skip_hwpoisoned_pages);
 void set_pageblock_migratetype(struct page *page, int migratetype);
 int move_freepages_block(struct zone *zone, struct page *page,
                                 int migratetype);
@@ -21,7 +22,7 @@ int move_freepages(struct zone *zone,
  */
 int
 start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
-                         unsigned migratetype);
+                         unsigned migratetype, bool skip_hwpoisoned_pages);
 
 /*
  * Changes MIGRATE_ISOLATE to MIGRATE_MOVABLE.
@@ -34,12 +35,13 @@ undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
 /*
  * Test all pages in [start_pfn, end_pfn) are isolated or not.
  */
-int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn);
+int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
+                        bool skip_hwpoisoned_pages);
 
 /*
  * Internal functions. Changes pageblock's migrate type.
  */
-int set_migratetype_isolate(struct page *page);
+int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages);
 void unset_migratetype_isolate(struct page *page, unsigned migratetype);
 struct page *alloc_migrate_target(struct page *page, unsigned long private,
                                 int **resultp);
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 8b20278be6a6..2c9fc7340b12 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1385,7 +1385,7 @@ static int get_any_page(struct page *p, unsigned long pfn, int flags)
          * Isolate the page, so that it doesn't get reallocated if it
          * was free.
          */
-        set_migratetype_isolate(p);
+        set_migratetype_isolate(p, true);
         /*
          * When the target page is a free hugepage, just remove it
          * from free hugepage list.
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index e4eeacae2b91..0095d156324a 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -847,7 +847,7 @@ check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
 {
         int ret;
         long offlined = *(long *)data;
-        ret = test_pages_isolated(start_pfn, start_pfn + nr_pages);
+        ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
         offlined = nr_pages;
         if (!ret)
                 *(long *)data += offlined;
@@ -894,7 +894,8 @@ static int __ref __offline_pages(unsigned long start_pfn,
         nr_pages = end_pfn - start_pfn;
 
         /* set above range as isolated */
-        ret = start_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
+        ret = start_isolate_page_range(start_pfn, end_pfn,
+                                       MIGRATE_MOVABLE, true);
         if (ret)
                 goto out;
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a49b0ea3cc2f..6f50cfe98a7b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5616,7 +5616,8 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags,
  * MIGRATE_MOVABLE block might include unmovable pages. It means you can't
  * expect this function should be exact.
  */
-bool has_unmovable_pages(struct zone *zone, struct page *page, int count)
+bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
+                         bool skip_hwpoisoned_pages)
 {
         unsigned long pfn, iter, found;
         int mt;
@@ -5651,6 +5652,13 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count)
                         continue;
                 }
 
+                /*
+                 * The HWPoisoned page may be not in buddy system, and
+                 * page_count() is not 0.
+                 */
+                if (skip_hwpoisoned_pages && PageHWPoison(page))
+                        continue;
+
                 if (!PageLRU(page))
                         found++;
                 /*
@@ -5693,7 +5701,7 @@ bool is_pageblock_removable_nolock(struct page *page)
                         zone->zone_start_pfn + zone->spanned_pages <= pfn)
                 return false;
 
-        return !has_unmovable_pages(zone, page, 0);
+        return !has_unmovable_pages(zone, page, 0, true);
 }
 
 #ifdef CONFIG_CMA
@@ -5864,7 +5872,8 @@ int alloc_contig_range(unsigned long start, unsigned long end,
          */
 
         ret = start_isolate_page_range(pfn_max_align_down(start),
-                                       pfn_max_align_up(end), migratetype);
+                                       pfn_max_align_up(end), migratetype,
+                                       false);
         if (ret)
                 return ret;
 
@@ -5903,7 +5912,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
         }
 
         /* Make sure the range is really isolated. */
-        if (test_pages_isolated(outer_start, end)) {
+        if (test_pages_isolated(outer_start, end, false)) {
                 pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
                        outer_start, end);
                 ret = -EBUSY;
@@ -6018,6 +6027,16 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
                         continue;
                 }
                 page = pfn_to_page(pfn);
+                /*
+                 * The HWPoisoned page may be not in buddy system, and
+                 * page_count() is not 0.
+                 */
+                if (unlikely(!PageBuddy(page) && PageHWPoison(page))) {
+                        pfn++;
+                        SetPageReserved(page);
+                        continue;
+                }
+
                 BUG_ON(page_count(page));
                 BUG_ON(!PageBuddy(page));
                 order = page_order(page);
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index f2f5b4818e94..9d2264ea4606 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -30,7 +30,7 @@ static void restore_pageblock_isolate(struct page *page, int migratetype)
         zone->nr_pageblock_isolate--;
 }
 
-int set_migratetype_isolate(struct page *page)
+int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages)
 {
         struct zone *zone;
         unsigned long flags, pfn;
@@ -66,7 +66,8 @@ int set_migratetype_isolate(struct page *page)
          * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.
          * We just check MOVABLE pages.
          */
-        if (!has_unmovable_pages(zone, page, arg.pages_found))
+        if (!has_unmovable_pages(zone, page, arg.pages_found,
+                                 skip_hwpoisoned_pages))
                 ret = 0;
 
         /*
@@ -134,7 +135,7 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
  * Returns 0 on success and -EBUSY if any part of range cannot be isolated.
  */
 int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
-                             unsigned migratetype)
+                             unsigned migratetype, bool skip_hwpoisoned_pages)
 {
         unsigned long pfn;
         unsigned long undo_pfn;
@@ -147,7 +148,8 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
              pfn < end_pfn;
              pfn += pageblock_nr_pages) {
                 page = __first_valid_page(pfn, pageblock_nr_pages);
-                if (page && set_migratetype_isolate(page)) {
+                if (page &&
+                    set_migratetype_isolate(page, skip_hwpoisoned_pages)) {
                         undo_pfn = pfn;
                         goto undo;
                 }
@@ -190,7 +192,8 @@ int undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
  * Returns 1 if all pages in the range are isolated.
  */
 static int
-__test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn)
+__test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
+                                  bool skip_hwpoisoned_pages)
 {
         struct page *page;
 
@@ -220,6 +223,14 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn)
                 else if (page_count(page) == 0 &&
                         get_freepage_migratetype(page) == MIGRATE_ISOLATE)
                         pfn += 1;
+                else if (skip_hwpoisoned_pages && PageHWPoison(page)) {
+                        /*
+                         * The HWPoisoned page may be not in buddy
+                         * system, and page_count() is not 0.
+                         */
+                        pfn++;
+                        continue;
+                }
                 else
                         break;
         }
@@ -228,7 +239,8 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn)
         return 1;
 }
 
-int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
+int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
+                        bool skip_hwpoisoned_pages)
 {
         unsigned long pfn, flags;
         struct page *page;
@@ -251,7 +263,8 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
         /* Check all pages are free or Marked as ISOLATED */
         zone = page_zone(page);
         spin_lock_irqsave(&zone->lock, flags);
-        ret = __test_page_isolated_in_pageblock(start_pfn, end_pfn);
+        ret = __test_page_isolated_in_pageblock(start_pfn, end_pfn,
+                                                skip_hwpoisoned_pages);
         spin_unlock_irqrestore(&zone->lock, flags);
         return ret ? 0 : -EBUSY;
 }