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>
This commit is contained in:
Vegard Nossum
2008-11-25 16:55:53 +01:00
parent 9b5cab3189
commit b1eeab6768
8 changed files with 122 additions and 31 deletions
+32 -13
View File
@@ -1,10 +1,10 @@
#include <linux/gfp.h>
#include <linux/mm_types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/kmemcheck.h>
void kmemcheck_alloc_shadow(struct kmem_cache *s, gfp_t flags, int node,
struct page *page, int order)
void kmemcheck_alloc_shadow(struct page *page, int order, gfp_t flags, int node)
{
struct page *shadow;
int pages;
@@ -16,7 +16,7 @@ void kmemcheck_alloc_shadow(struct kmem_cache *s, gfp_t flags, int node,
* With kmemcheck enabled, we need to allocate a memory area for the
* shadow bits as well.
*/
shadow = alloc_pages_node(node, flags, order);
shadow = alloc_pages_node(node, flags | __GFP_NOTRACK, order);
if (!shadow) {
if (printk_ratelimit())
printk(KERN_ERR "kmemcheck: failed to allocate "
@@ -33,23 +33,17 @@ void kmemcheck_alloc_shadow(struct kmem_cache *s, gfp_t flags, int node,
* the memory accesses.
*/
kmemcheck_hide_pages(page, pages);
/*
* Objects from caches that have a constructor don't get
* cleared when they're allocated, so we need to do it here.
*/
if (s->ctor)
kmemcheck_mark_uninitialized_pages(page, pages);
else
kmemcheck_mark_unallocated_pages(page, pages);
}
void kmemcheck_free_shadow(struct kmem_cache *s, struct page *page, int order)
void kmemcheck_free_shadow(struct page *page, int order)
{
struct page *shadow;
int pages;
int i;
if (!kmemcheck_page_is_tracked(page))
return;
pages = 1 << order;
kmemcheck_show_pages(page, pages);
@@ -101,3 +95,28 @@ void kmemcheck_slab_free(struct kmem_cache *s, void *object, size_t size)
if (!s->ctor && !(s->flags & SLAB_DESTROY_BY_RCU))
kmemcheck_mark_freed(object, size);
}
void kmemcheck_pagealloc_alloc(struct page *page, unsigned int order,
gfp_t gfpflags)
{
int pages;
if (gfpflags & (__GFP_HIGHMEM | __GFP_NOTRACK))
return;
pages = 1 << order;
/*
* NOTE: We choose to track GFP_ZERO pages too; in fact, they
* can become uninitialized by copying uninitialized memory
* into them.
*/
/* XXX: Can use zone->node for node? */
kmemcheck_alloc_shadow(page, order, gfpflags, -1);
if (gfpflags & __GFP_ZERO)
kmemcheck_mark_initialized_pages(page, pages);
else
kmemcheck_mark_uninitialized_pages(page, pages);
}