Re: [PATCH v2 1/2] mm: Uncharge poisoned pages

From: Balbir Singh
Date: Wed May 03 2017 - 21:21:25 EST


> @@ -5527,7 +5527,7 @@ static void uncharge_list(struct list_head *page_list)
> next = page->lru.next;
>
> VM_BUG_ON_PAGE(PageLRU(page), page);
> - VM_BUG_ON_PAGE(page_count(page), page);
> + VM_BUG_ON_PAGE(!PageHWPoison(page) && page_count(page), page);
>
> if (!page->mem_cgroup)
> continue;
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index 8a6bd3a9eb1e..4497d9619bb4 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -541,6 +541,13 @@ static int delete_from_lru_cache(struct page *p)
> */
> ClearPageActive(p);
> ClearPageUnevictable(p);
> +
> + /*
> + * Poisoned page might never drop its ref count to 0 so we have to
> + * uncharge it manually from its memcg.
> + */
> + mem_cgroup_uncharge(p);
> +

Yep, that is the right fix

https://lkml.org/lkml/2017/4/26/133

Reviewed-by: Balbir Singh <bsingharora@xxxxxxxxx>