On Tue, 27 Jun 2023 19:28:08 +0800 Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote:
> When page_handle_poison() fails to handle the hugepage or free page in
> retry path, soft_offline_page() will return 0 while -EBUSY is expected
> in this case.
What are the user visible effects of the bug?
> Fixes: b94e02822deb ("mm,hwpoison: try to narrow window race for free pages")
>
> ...
>
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -2737,10 +2737,13 @@ int soft_offline_page(unsigned long pfn, int flags)
> if (ret > 0) {
> ret = soft_offline_in_use_page(page);
> } else if (ret == 0) {
> - if (!page_handle_poison(page, true, false) && try_again) {
> - try_again = false;
> - flags &= ~MF_COUNT_INCREASED;
> - goto retry;
> + if (!page_handle_poison(page, true, false)) {
> + if (try_again) {
> + try_again = false;
> + flags &= ~MF_COUNT_INCREASED;
> + goto retry;
> + }
> + ret = -EBUSY;
> }
> }
