On 2022/4/27 12:28, Naoya Horiguchi wrote:
> From: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
>
> When offlining memory section with hwpoisoned pages, the hwpoisons are
> canceled. But num_poisoned_pages is not updated for that event, so the
> counter becomes inconsistent.
IIUC, this work is already done via clear_hwpoisoned_pages when __remove_pages.
Or am I miss something?
Thanks!
>
> Add num_poisoned_pages_dec() in __offline_isolated_pages(). PageHWPoison
> can be set on a tail page of some high order buddy page, so we need check
> PageHWPoison on each subpage.
>
> Signed-off-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
> ---
> mm/page_alloc.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 6e5b4488a0c5..dcd962855617 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -9487,12 +9487,15 @@ void __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
> zone = page_zone(pfn_to_page(pfn));
> spin_lock_irqsave(&zone->lock, flags);
> while (pfn < end_pfn) {
> + int i;
> +
> page = pfn_to_page(pfn);
> /*
> * The HWPoisoned page may be not in buddy system, and
> * page_count() is not 0.
> */
> if (unlikely(!PageBuddy(page) && PageHWPoison(page))) {
> + num_poisoned_pages_dec();
> pfn++;
> continue;
> }
> @@ -9510,6 +9513,9 @@ void __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
> BUG_ON(page_count(page));
> BUG_ON(!PageBuddy(page));
> order = buddy_order(page);
> + for (i = 0; i < 1 << order; i++)
> + if (PageHWPoison(page + i))
> + num_poisoned_pages_dec();
> del_page_from_free_list(page, zone, order);
> pfn += (1 << order);
> }
>
