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

Qi Zheng
2025-11-20T13:41:39Z

On 11/20/25 5:52 PM, Harry Yoo wrote:
> 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.

Right, will fix it in the version.

>
>> 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>

Thanks!

>