kmemcheck: add hooks for the page allocator

This adds support for tracking the initializedness of memory that
was allocated with the page allocator. Highmem requests are not
tracked.

Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>

[build fix for !CONFIG_KMEMCHECK]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>

1 files changed, 10 insertions, 5 deletions

diff --git a/mm/slab.c b/mm/slab.c
index 95b6c5eb40b3..6a1ad0b9a94f 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1612,7 +1612,7 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
         if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
                 flags |= __GFP_RECLAIMABLE;
 
-        page = alloc_pages_node(nodeid, flags, cachep->gfporder);
+        page = alloc_pages_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder);
         if (!page)
                 return NULL;
 
@@ -1626,8 +1626,14 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
         for (i = 0; i < nr_pages; i++)
                 __SetPageSlab(page + i);
 
-        if (kmemcheck_enabled && !(cachep->flags & SLAB_NOTRACK))
-                kmemcheck_alloc_shadow(cachep, flags, nodeid, page, cachep->gfporder);
+        if (kmemcheck_enabled && !(cachep->flags & SLAB_NOTRACK)) {
+                kmemcheck_alloc_shadow(page, cachep->gfporder, flags, nodeid);
+
+                if (cachep->ctor)
+                        kmemcheck_mark_uninitialized_pages(page, nr_pages);
+                else
+                        kmemcheck_mark_unallocated_pages(page, nr_pages);
+        }
 
         return page_address(page);
 }
@@ -1641,8 +1647,7 @@ static void kmem_freepages(struct kmem_cache *cachep, void *addr)
         struct page *page = virt_to_page(addr);
         const unsigned long nr_freed = i;
 
-        if (kmemcheck_page_is_tracked(page))
-                kmemcheck_free_shadow(cachep, page, cachep->gfporder);
+        kmemcheck_free_shadow(page, cachep->gfporder);
 
         if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
                 sub_zone_page_state(page_zone(page),