1 files changed, 7 insertions, 13 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 47a6812f5f8c..e3b1362372c2 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -395,6 +395,9 @@ void free_swap_and_cache(swp_entry_t entry)
         struct swap_info_struct * p;
         struct page *page = NULL;
 
+        if (is_migration_entry(entry))
+                return;
+
         p = swap_info_get(entry);
         if (p) {
                 if (swap_entry_free(p, swp_offset(entry)) == 1) {
@@ -1400,19 +1403,7 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
                 if (!(p->flags & SWP_USED))
                         break;
         error = -EPERM;
-        /*
-         * Test if adding another swap device is possible. There are
-         * two limiting factors: 1) the number of bits for the swap
-         * type swp_entry_t definition and 2) the number of bits for
-         * the swap type in the swap ptes as defined by the different
-         * architectures. To honor both limitations a swap entry
-         * with swap offset 0 and swap type ~0UL is created, encoded
-         * to a swap pte, decoded to a swp_entry_t again and finally
-         * the swap type part is extracted. This will mask all bits
-         * from the initial ~0UL that can't be encoded in either the
-         * swp_entry_t or the architecture definition of a swap pte.
-         */
-        if (type > swp_type(pte_to_swp_entry(swp_entry_to_pte(swp_entry(~0UL,0))))) {
+        if (type >= MAX_SWAPFILES) {
                 spin_unlock(&swap_lock);
                 goto out;
         }
@@ -1702,6 +1693,9 @@ int swap_duplicate(swp_entry_t entry)
         unsigned long offset, type;
         int result = 0;
 
+        if (is_migration_entry(entry))
+                return 1;
+
         type = swp_type(entry);
         if (type >= nr_swapfiles)
                 goto bad_file;