3 files changed, 17 insertions, 5 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 9abc6008544b..85e80a57db29 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -623,11 +623,12 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
                         (*zap_work)--;
                         continue;
                 }
+
+                (*zap_work) -= PAGE_SIZE;
+
                 if (pte_present(ptent)) {
                         struct page *page;
 
-                        (*zap_work) -= PAGE_SIZE;
-
                         page = vm_normal_page(vma, addr, ptent);
                         if (unlikely(details) && page) {
                                 /*
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 2a8206009422..b21869a39f0b 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -330,9 +330,19 @@ check_range(struct mm_struct *mm, unsigned long start, unsigned long end,
         int err;
         struct vm_area_struct *first, *vma, *prev;
 
-        /* Clear the LRU lists so pages can be isolated */
-        if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
+        if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
+                /* Must have swap device for migration */
+                if (nr_swap_pages <= 0)
+                        return ERR_PTR(-ENODEV);
+
+                /*
+                 * Clear the LRU lists so pages can be isolated.
+                 * Note that pages may be moved off the LRU after we have
+                 * drained them. Those pages will fail to migrate like other
+                 * pages that may be busy.
+                 */
                 lru_add_drain_all();
+        }
 
         first = find_vma(mm, start);
         if (!first)
diff --git a/mm/swap.c b/mm/swap.c
index e9ec06d845e8..b524ea90bddb 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -393,7 +393,8 @@ void pagevec_strip(struct pagevec *pvec)
                 struct page *page = pvec->pages[i];
 
                 if (PagePrivate(page) && !TestSetPageLocked(page)) {
-                        try_to_release_page(page, 0);
+                        if (PagePrivate(page))
+                                try_to_release_page(page, 0);
                         unlock_page(page);
                 }
         }