Re: [PATCH v2 4/8] mm/memory-failure: convert process iterator to for_each_process_rculock

From: SJ Park

Date: Mon Sep 07 2026 - 17:29:36 EST


On Mon, 7 Sep 2026 16:13:30 +0800 Ye Liu <ye.liu@xxxxxxxxx> wrote:

> From: Ye Liu <liuye@xxxxxxxxxx>
>
> Replace the manual rcu_read_lock()/rcu_read_unlock() pairs combined
> with for_each_process() loop in mm/memory-failure.c with
> for_each_process_rculock(), which scopes the RCU read lock to the
> loop body via scoped_guard(rcu).
>
> In collect_procs_file(), the page_pgoff() call now falls outside the
> RCU read-side critical section. This is safe because page_pgoff()
> only reads folio->index and does not traverse any RCU-protected
> structures.

Thank you for clarifying :)

>
> Signed-off-by: Ye Liu <liuye@xxxxxxxxxx>
> Acked-by: Michal Hocko <mhocko@xxxxxxxx>
> Acked-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>

Reviewed-by: SJ Park <sj@xxxxxxxxxx>


Thanks,
SJ

[...]