On Tue, 16 Nov 2021 at 01:16, Vlastimil Babka <vbabka@xxxxxxx> wrote:
> The function sets some fields that are being moved from struct page to struct
> slab so it needs to be converted.
>
> Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
> Cc: Alexander Potapenko <glider@xxxxxxxxxx>
> Cc: Marco Elver <elver@xxxxxxxxxx>
> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> Cc: <kasan-dev@xxxxxxxxxxxxxxxx>
It looks sane. I ran kfence_test with both slab and slub, and all passes:
Tested-by: Marco Elver <elver@xxxxxxxxxx>
But should there be other major changes, we should re-test.
Thanks,
-- Marco
> ---
> mm/kfence/core.c | 12 ++++++------
> mm/kfence/kfence_test.c | 6 +++---
> 2 files changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/mm/kfence/core.c b/mm/kfence/core.c
> index 09945784df9e..4eb60cf5ff8b 100644
> --- a/mm/kfence/core.c
> +++ b/mm/kfence/core.c
> @@ -360,7 +360,7 @@ static void *kfence_guarded_alloc(struct kmem_cache *cache, size_t size, gfp_t g
> {
> struct kfence_metadata *meta = NULL;
> unsigned long flags;
> - struct page *page;
> + struct slab *slab;
> void *addr;
>
> /* Try to obtain a free object. */
> @@ -424,13 +424,13 @@ static void *kfence_guarded_alloc(struct kmem_cache *cache, size_t size, gfp_t g
>
> alloc_covered_add(alloc_stack_hash, 1);
>
> - /* Set required struct page fields. */
> - page = virt_to_page(meta->addr);
> - page->slab_cache = cache;
> + /* Set required slab fields. */
> + slab = virt_to_slab((void *)meta->addr);
> + slab->slab_cache = cache;
> if (IS_ENABLED(CONFIG_SLUB))
> - page->objects = 1;
> + slab->objects = 1;
> if (IS_ENABLED(CONFIG_SLAB))
> - page->s_mem = addr;
> + slab->s_mem = addr;
>
> /* Memory initialization. */
> for_each_canary(meta, set_canary_byte);
> diff --git a/mm/kfence/kfence_test.c b/mm/kfence/kfence_test.c
> index f7276711d7b9..a22b1af85577 100644
> --- a/mm/kfence/kfence_test.c
> +++ b/mm/kfence/kfence_test.c
> @@ -282,7 +282,7 @@ static void *test_alloc(struct kunit *test, size_t size, gfp_t gfp, enum allocat
> alloc = kmalloc(size, gfp);
>
> if (is_kfence_address(alloc)) {
> - struct page *page = virt_to_head_page(alloc);
> + struct slab *slab = virt_to_slab(alloc);
> struct kmem_cache *s = test_cache ?:
> kmalloc_caches[kmalloc_type(GFP_KERNEL)][__kmalloc_index(size, false)];
>
> @@ -291,8 +291,8 @@ static void *test_alloc(struct kunit *test, size_t size, gfp_t gfp, enum allocat
> * even for KFENCE objects; these are required so that
> * memcg accounting works correctly.
> */
> - KUNIT_EXPECT_EQ(test, obj_to_index(s, page_slab(page), alloc), 0U);
> - KUNIT_EXPECT_EQ(test, objs_per_slab(s, page_slab(page)), 1);
> + KUNIT_EXPECT_EQ(test, obj_to_index(s, slab, alloc), 0U);
> + KUNIT_EXPECT_EQ(test, objs_per_slab(s, slab), 1);
>
> if (policy == ALLOCATE_ANY)
> return alloc;
> --
> 2.33.1
