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From: Kuniyuki Iwashima To: Alexander Potapenko Cc: Andrey Ryabinin , Andrew Morton , Vlastimil Babka , Harry Yoo , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , kasan-dev@googlegroups.com, linux-mm@kvack.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 9634C40003 X-Stat-Signature: zjjsnwbqwuj8spokjkys7f7s59xmpw9r X-Rspamd-Server: rspam01 X-Spam-Status: No, score=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=4.0.1 X-HE-Tag: 1793137890-410655 X-HE-Meta: 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 uHgKry8Q 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Tue, 27 Oct 2026 13:48:03 +0100, Alexander Potapenko wrote: > On Fri, Oct 9, 2026 at 11:46=E2=80=AFPM Kuniyuki Iwashima wrote: >=20 > > The bit is marked along with recording the stack trace when > > deferring slab frees in kfree_rcu_sheaf() and checked in > > check_slab_allocation() so that any double-free pattern above > > can be detected immediately. > > > > Link: https://lore.kernel.org/all/6ac959ee.70ed5d86.2ac85.007d.GAE@goog= le.com/ #[0] > > Signed-off-by: Kuniyuki Iwashima > Tested-by: Alexander Potapenko >=20 > Do we need a Fixes: tag? Will add Fixes: ec66e0d59952 ("slab: add sheaf support for batching kfree_rcu() oper= ations") >=20 >=20 >=20 >=20 > > */ > > static __always_inline bool kasan_slab_pre_free(struct kmem_cache *s, > > - void *object) > > + void *object, > > + bool after_rcu_delay) >=20 > Please update the doc comment as well. Will do. >=20 >=20 > > poison_slab_object(slab->slab_cache, ptr, false); > > diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c > > index 2b8e73f5f6a7..07636ffe1626 100644 > > --- a/mm/kasan/generic.c > > +++ b/mm/kasan/generic.c > > @@ -536,7 +536,7 @@ size_t kasan_metadata_size(struct kmem_cache *cache= , bool in_object) > > * This function avoids dynamic memory allocations and thus can be cal= led from > > * contexts that do not allow allocating memory. > > */ >=20 > Please update the comment for this function. Will do. >=20 >=20 > > +void kasan_record_aux_stack(void *addr) > > +{ > > + __kasan_record_aux_stack(addr, false); > > +} > > + >=20 > I think there's an important distinction between > kasan_record_aux_stack() and kasan_record_aux_stack_rcu(): namely, it > affects how this object is handled later. > Let's somehow reflect this in a comment ("records the aux stack and > arms the check") and perhaps rename it to something like > kasan_mark_rcu_free_pending()? Sure, will rename to it and add comments. >=20 > Otherwise the series looks good, I'll be happy to stamp it once you > fix the comments. >=20 Thank you !