1 files changed, 11 insertions, 8 deletions

diff --git a/mm/internal.h b/mm/internal.h
index a346ba1..612c14f 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -27,8 +27,8 @@ static inline void set_page_count(struct page *page, int v)
  */
 static inline void set_page_refcounted(struct page *page)
 {
-	VM_BUG_ON(PageTail(page));
-	VM_BUG_ON(atomic_read(&page->_count));
+	VM_BUG_ON_PAGE(PageTail(page), page);
+	VM_BUG_ON_PAGE(atomic_read(&page->_count), page);
 	set_page_count(page, 1);
 }
 
@@ -46,7 +46,7 @@ static inline void __get_page_tail_foll(struct page *page,
 	 * speculative page access (like in
 	 * page_cache_get_speculative()) on tail pages.
 	 */
-	VM_BUG_ON(atomic_read(&page->first_page->_count) <= 0);
+	VM_BUG_ON_PAGE(atomic_read(&page->first_page->_count) <= 0, page);
 	if (get_page_head)
 		atomic_inc(&page->first_page->_count);
 	get_huge_page_tail(page);
@@ -71,7 +71,7 @@ static inline void get_page_foll(struct page *page)
 		 * Getting a normal page or the head of a compound page
 		 * requires to already have an elevated page->_count.
 		 */
-		VM_BUG_ON(atomic_read(&page->_count) <= 0);
+		VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page);
 		atomic_inc(&page->_count);
 	}
 }
@@ -99,6 +99,7 @@ extern void prep_compound_page(struct page *page, unsigned long order);
 #ifdef CONFIG_MEMORY_FAILURE
 extern bool is_free_buddy_page(struct page *page);
 #endif
+extern int user_min_free_kbytes;
 
 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
 
@@ -142,9 +143,11 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
 #endif
 
 /*
- * function for dealing with page's order in buddy system.
- * zone->lock is already acquired when we use these.
- * So, we don't need atomic page->flags operations here.
+ * This function returns the order of a free page in the buddy system. In
+ * general, page_zone(page)->lock must be held by the caller to prevent the
+ * page from being allocated in parallel and returning garbage as the order.
+ * If a caller does not hold page_zone(page)->lock, it must guarantee that the
+ * page cannot be allocated or merged in parallel.
  */
 static inline unsigned long page_order(struct page *page)
 {
@@ -173,7 +176,7 @@ static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
 static inline int mlocked_vma_newpage(struct vm_area_struct *vma,
 				    struct page *page)
 {
-	VM_BUG_ON(PageLRU(page));
+	VM_BUG_ON_PAGE(PageLRU(page), page);
 
 	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
 		return 0;