PM / Hibernate: Fix memory corruption related to swap

[lisovros/linux_canprio.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index f12ad1836abe115b1b8e3bf4b9187c01249e8a30..2bd6f6da38ea5d93332c4bb6cb5799fcd489cb9b 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -103,19 +103,24 @@ gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
  * only be modified with pm_mutex held, unless the suspend/hibernate code is
  * guaranteed not to run in parallel with that modification).
  */
-void set_gfp_allowed_mask(gfp_t mask)
+
+static gfp_t saved_gfp_mask;
+
+void pm_restore_gfp_mask(void)
 {
        WARN_ON(!mutex_is_locked(&pm_mutex));
-       gfp_allowed_mask = mask;
+       if (saved_gfp_mask) {
+               gfp_allowed_mask = saved_gfp_mask;
+               saved_gfp_mask = 0;
+       }
 }
 
-gfp_t clear_gfp_allowed_mask(gfp_t mask)
+void pm_restrict_gfp_mask(void)
 {
-       gfp_t ret = gfp_allowed_mask;
-
        WARN_ON(!mutex_is_locked(&pm_mutex));
-       gfp_allowed_mask &= ~mask;
-       return ret;
+       WARN_ON(saved_gfp_mask);
+       saved_gfp_mask = gfp_allowed_mask;
+       gfp_allowed_mask &= ~GFP_IOFS;
 }
 #endif /* CONFIG_PM_SLEEP */
 
@@ -530,7 +535,7 @@ static inline void __free_one_page(struct page *page,
         * so it's less likely to be used soon and more likely to be merged
         * as a higher order page
         */
-       if ((order < MAX_ORDER-1) && pfn_valid_within(page_to_pfn(buddy))) {
+       if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) {
                struct page *higher_page, *higher_buddy;
                combined_idx = __find_combined_index(page_idx, order);
                higher_page = page + combined_idx - page_idx;