diff --git a/mm/slub.c b/mm/slub.c index c4f40d373d1e5ec7050671faa8a109031c76f2ee..69ee7f807e84595a395eccd142d54105292c7dd6 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -670,8 +670,6 @@ static void add_full(struct kmem_cache *s, struct page *page) VM_BUG_ON(!irqs_disabled()); - VM_BUG_ON(!irqs_disabled()); - if (!(s->flags & SLAB_STORE_USER)) return; @@ -2551,6 +2549,99 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, #ifdef CONFIG_SYSFS +static int validate_slab(struct kmem_cache *s, struct page *page) +{ + void *p; + void *addr = page_address(page); + unsigned long map[BITS_TO_LONGS(s->objects)]; + + if (!check_slab(s, page) || + !on_freelist(s, page, NULL)) + return 0; + + /* Now we know that a valid freelist exists */ + bitmap_zero(map, s->objects); + + for(p = page->freelist; p; p = get_freepointer(s, p)) { + set_bit((p - addr) / s->size, map); + if (!check_object(s, page, p, 0)) + return 0; + } + + for(p = addr; p < addr + s->objects * s->size; p += s->size) + if (!test_bit((p - addr) / s->size, map)) + if (!check_object(s, page, p, 1)) + return 0; + return 1; +} + +static void validate_slab_slab(struct kmem_cache *s, struct page *page) +{ + if (slab_trylock(page)) { + validate_slab(s, page); + slab_unlock(page); + } else + printk(KERN_INFO "SLUB %s: Skipped busy slab 0x%p\n", + s->name, page); + + if (s->flags & DEBUG_DEFAULT_FLAGS) { + if (!PageError(page)) + printk(KERN_ERR "SLUB %s: PageError not set " + "on slab 0x%p\n", s->name, page); + } else { + if (PageError(page)) + printk(KERN_ERR "SLUB %s: PageError set on " + "slab 0x%p\n", s->name, page); + } +} + +static int validate_slab_node(struct kmem_cache *s, struct kmem_cache_node *n) +{ + unsigned long count = 0; + struct page *page; + unsigned long flags; + + spin_lock_irqsave(&n->list_lock, flags); + + list_for_each_entry(page, &n->partial, lru) { + validate_slab_slab(s, page); + count++; + } + if (count != n->nr_partial) + printk(KERN_ERR "SLUB %s: %ld partial slabs counted but " + "counter=%ld\n", s->name, count, n->nr_partial); + + if (!(s->flags & SLAB_STORE_USER)) + goto out; + + list_for_each_entry(page, &n->full, lru) { + validate_slab_slab(s, page); + count++; + } + if (count != atomic_long_read(&n->nr_slabs)) + printk(KERN_ERR "SLUB: %s %ld slabs counted but " + "counter=%ld\n", s->name, count, + atomic_long_read(&n->nr_slabs)); + +out: + spin_unlock_irqrestore(&n->list_lock, flags); + return count; +} + +static unsigned long validate_slab_cache(struct kmem_cache *s) +{ + int node; + unsigned long count = 0; + + flush_all(s); + for_each_online_node(node) { + struct kmem_cache_node *n = get_node(s, node); + + count += validate_slab_node(s, n); + } + return count; +} + static unsigned long count_partial(struct kmem_cache_node *n) { unsigned long flags; @@ -2680,7 +2771,6 @@ struct slab_attribute { static struct slab_attribute _name##_attr = \ __ATTR(_name, 0644, _name##_show, _name##_store) - static ssize_t slab_size_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%d\n", s->size); @@ -2886,6 +2976,22 @@ static ssize_t store_user_store(struct kmem_cache *s, } SLAB_ATTR(store_user); +static ssize_t validate_show(struct kmem_cache *s, char *buf) +{ + return 0; +} + +static ssize_t validate_store(struct kmem_cache *s, + const char *buf, size_t length) +{ + if (buf[0] == '1') + validate_slab_cache(s); + else + return -EINVAL; + return length; +} +SLAB_ATTR(validate); + #ifdef CONFIG_NUMA static ssize_t defrag_ratio_show(struct kmem_cache *s, char *buf) { @@ -2925,6 +3031,7 @@ static struct attribute * slab_attrs[] = { &red_zone_attr.attr, &poison_attr.attr, &store_user_attr.attr, + &validate_attr.attr, #ifdef CONFIG_ZONE_DMA &cache_dma_attr.attr, #endif