On Tue, Dec 13, 2022 at 01:44:46PM -0500, Waiman Long wrote: > + /* > + * Flush all the non-empty percpu lockless lists so as to release > + * the blkg references held by those lists which, in turn, may > + * allow the blkgs to be freed and release their references to > + * blkcg speeding up its freeing. > + */ Can you mention the possible deadlock explicitly? This sounds more like an optimization. Thanks. -- tejun