Re: [PATCH v1 19/26] mm: swap: prevent lruvec release in swap module

Harry Yoo
2025-11-20T09:53:50Z

On Tue, Oct 28, 2025 at 09:58:32PM +0800, Qi Zheng wrote:
> From: Muchun Song <songmuchun@bytedance.com>
>
> In the near future, a folio will no longer pin its corresponding
> memory cgroup. So an lruvec returned by folio_lruvec() could be
> released without the rcu read lock or a reference to its memory
> cgroup.
>
> In the current patch, the rcu read lock is employed to safeguard
> against the release of the lruvec in lru_note_cost_refault() and
> lru_activate().

nit: the above paragraph looks incorrect.

> This serves as a preparatory measure for the reparenting of the
> LRU pages.
>
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
> ---

Looks good to me,
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>

--
Cheers,
Harry / Hyeonggon