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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240730-kasan-tsbrcu-v5-2-48d3cbdfccc5@google.com> User-Agent: Mutt/2.2.12 (2023-09-09) On Tue, Jul 30, 2024 at 01:06PM +0200, Jann Horn wrote: [...] > +#ifdef CONFIG_SLUB_RCU_DEBUG > + if ((s->flags & SLAB_TYPESAFE_BY_RCU) && !after_rcu_delay) { > + struct rcu_delayed_free *delayed_free; > + > + delayed_free = kmalloc(sizeof(*delayed_free), GFP_NOWAIT); This may well be allocated by KFENCE. [...] > +#ifdef CONFIG_SLUB_RCU_DEBUG > +static void slab_free_after_rcu_debug(struct rcu_head *rcu_head) > +{ > + struct rcu_delayed_free *delayed_free = > + container_of(rcu_head, struct rcu_delayed_free, head); > + void *object = delayed_free->object; > + struct slab *slab = virt_to_slab(object); > + struct kmem_cache *s; > + > + if (WARN_ON(is_kfence_address(rcu_head))) > + return; syzbot found this warning to trigger (because see above comment): https://lore.kernel.org/all/00000000000052aa15061eaeb1fd@google.com/ Should this have been `is_kfence_address(object)`?