3 files changed, 21 insertions, 7 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index f945dff34925..2e40a44a1fae 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -903,7 +903,9 @@ extern int page_to_nid(const struct page *page);
 #else
 static inline int page_to_nid(const struct page *page)
 {
-        return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
+        struct page *p = (struct page *)page;
+
+        return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK;
 }
 #endif
 
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 50c2b8786831..e34a27727b9a 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -156,9 +156,18 @@ static __always_inline int PageCompound(struct page *page)
         return test_bit(PG_head, &page->flags) || PageTail(page);
 }
 
+#define PAGE_POISON_PATTERN     -1l
+static inline int PagePoisoned(const struct page *page)
+{
+        return page->flags == PAGE_POISON_PATTERN;
+}
+
 /*
  * Page flags policies wrt compound pages
  *
+ * PF_POISONED_CHECK
+ *     check if this struct page poisoned/uninitialized
+ *
  * PF_ANY:
  *     the page flag is relevant for small, head and tail pages.
  *
@@ -176,17 +185,20 @@ static __always_inline int PageCompound(struct page *page)
  * PF_NO_COMPOUND:
  *     the page flag is not relevant for compound pages.
  */
-#define PF_ANY(page, enforce)   page
-#define PF_HEAD(page, enforce)  compound_head(page)
+#define PF_POISONED_CHECK(page) ({                                      \
+                VM_BUG_ON_PGFLAGS(PagePoisoned(page), page);            \
+                page; })
+#define PF_ANY(page, enforce)   PF_POISONED_CHECK(page)
+#define PF_HEAD(page, enforce)  PF_POISONED_CHECK(compound_head(page))
 #define PF_ONLY_HEAD(page, enforce) ({                                  \
                 VM_BUG_ON_PGFLAGS(PageTail(page), page);                \
-                page;})
+                PF_POISONED_CHECK(page); })
 #define PF_NO_TAIL(page, enforce) ({                                    \
                 VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page);     \
-                compound_head(page);})
+                PF_POISONED_CHECK(compound_head(page)); })
 #define PF_NO_COMPOUND(page, enforce) ({                                \
                 VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \
-                page;})
+                PF_POISONED_CHECK(page); })
 
 /*
  * Macros to create function definitions for page flags
diff --git a/mm/memblock.c b/mm/memblock.c
index f7f76513a0c5..c2fed302c2f8 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1345,7 +1345,7 @@ void * __init memblock_virt_alloc_try_nid_raw(
                                            min_addr, max_addr, nid);
 #ifdef CONFIG_DEBUG_VM
         if (ptr && size > 0)
-                memset(ptr, 0xff, size);
+                memset(ptr, PAGE_POISON_PATTERN, size);
 #endif
         return ptr;
 }