diff options
Diffstat (limited to 'mm/kmemcheck.c')
-rw-r--r-- | mm/kmemcheck.c | 125 |
1 files changed, 0 insertions, 125 deletions
diff --git a/mm/kmemcheck.c b/mm/kmemcheck.c index b3a4d61d341c..cec594032515 100644 --- a/mm/kmemcheck.c +++ b/mm/kmemcheck.c @@ -1,126 +1 @@ // SPDX-License-Identifier: GPL-2.0 -#include <linux/gfp.h> -#include <linux/mm_types.h> -#include <linux/mm.h> -#include <linux/slab.h> -#include "slab.h" -#include <linux/kmemcheck.h> - -void kmemcheck_alloc_shadow(struct page *page, int order, gfp_t flags, int node) -{ - struct page *shadow; - int pages; - int i; - - pages = 1 << order; - - /* - * With kmemcheck enabled, we need to allocate a memory area for the - * shadow bits as well. - */ - shadow = alloc_pages_node(node, flags, order); - if (!shadow) { - if (printk_ratelimit()) - pr_err("kmemcheck: failed to allocate shadow bitmap\n"); - return; - } - - for(i = 0; i < pages; ++i) - page[i].shadow = page_address(&shadow[i]); - - /* - * Mark it as non-present for the MMU so that our accesses to - * this memory will trigger a page fault and let us analyze - * the memory accesses. - */ - kmemcheck_hide_pages(page, pages); -} - -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); - - shadow = virt_to_page(page[0].shadow); - - for(i = 0; i < pages; ++i) - page[i].shadow = NULL; - - __free_pages(shadow, order); -} - -void kmemcheck_slab_alloc(struct kmem_cache *s, gfp_t gfpflags, void *object, - size_t size) -{ - if (unlikely(!object)) /* Skip object if allocation failed */ - return; - - /* - * Has already been memset(), which initializes the shadow for us - * as well. - */ - if (gfpflags & __GFP_ZERO) - return; - - /* No need to initialize the shadow of a non-tracked slab. */ - if (s->flags & SLAB_NOTRACK) - return; - - if (!kmemcheck_enabled || gfpflags & __GFP_NOTRACK) { - /* - * Allow notracked objects to be allocated from - * tracked caches. Note however that these objects - * will still get page faults on access, they just - * won't ever be flagged as uninitialized. If page - * faults are not acceptable, the slab cache itself - * should be marked NOTRACK. - */ - kmemcheck_mark_initialized(object, size); - } else if (!s->ctor) { - /* - * New objects should be marked uninitialized before - * they're returned to the called. - */ - kmemcheck_mark_uninitialized(object, size); - } -} - -void kmemcheck_slab_free(struct kmem_cache *s, void *object, size_t size) -{ - /* TODO: RCU freeing is unsupported for now; hide false positives. */ - if (!s->ctor && !(s->flags & SLAB_TYPESAFE_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); -} |